X. DEFORMITIES OF THE EXTREMITIES
The origin of deformities: (1) Those arising before birth; (2) those produced during birth; and (3) those acquired after birth.
Palsies of children: Anterior Poliomyelitis. Cerebral palsies: Spastic paralysis.
THE LOWER EXTREMITY: Congenital dislocation of hip--Snapping hip--Paralytic deformities--Contracture and ankylosis of hip--Coxa vara and coxa valga--Congenital dislocation of knee and patella--Genu recurvatum--Paralytic deformities--Contracture and ankylosis of knee--Genu valgum and genu varum--Congenital deformities of leg--Bow-leg--Club-foot: Talipes equino-varus; Pes equinus; Pes calcaneus; Pes calcaneo-valgus and varus; Pes cavus; Flat-foot and pes valgus--Painful affections of heel--Metatarsalgia--Hallux valgus and bunion--Hallux varus--Hallux rigidus and flexus--Hammer-toe--Hypertrophy of toes--Supernumerary toes--Webbed toes.
THE UPPER EXTREMITY: Congenital absence of clavicle--Elevation of scapula--Winged scapula--Congenital paralytic deformities of shoulder--Deformities of elbow--Club-hand--Deformities of wrist--Madelung's deformity--Deformities of fingers--Dupuytren's contraction--Polydactylism.
The surgery of the extremities is so largely concerned with the correction of deformities that it is necessary at the outset to refer briefly to some points relating to the time and mode of origin of these.
1. Congenital deformities--that is, those which originate in utero and are present at birth--are comparatively common and may be due to a variety of causes. Some result from errors of development--for example, supernumerary fingers or toes, and deficiencies in the bones of the leg or forearm. A larger number are to be attributed to a persistent abnormal attitude of the foetus, usually associated with want of room in the uterus--for example, the common form of club-foot and congenital dislocation of the hip. Less frequently amniotic bands so constrict the digits or the limbs as to produce distortion, or even to sever the distal part--intra-uterine amputation. Lastly, certain diseases of the foetus, and particularly such as affect the skeleton--for example, achondroplasia--cause congenital deformities.
2. Deformities originating during birth are all traceable to the effects of injuries sustained in the course of a difficult labour. Examples of these are: wry-neck resulting from rupture of the sterno-mastoid; lesions of the shoulder-joint and brachial plexus due to hyper-extension of the arm; a spastic condition of the lower limbs--Little's disease--resulting from tearing of blood vessels on the surface of the brain with haemorrhage and interference with the function of the cortical motor area.
3. Deformities acquired after birth arise from widely different causes, of which diseases of bone, including rickets, diseases of joints, and affections of the nervous system attended with paralysis, are amongst the commonest. Other deformities are produced by unsuitable clothing, such as a tight corset, or ill-fitting shoes distorting the toes, prolonged standing in growing subjects overstraining the mechanism of the foot and giving rise to the common form of flat-foot.
The part played by the palsies of children in the surgical affections of the extremities necessitates a short description of their more important features.
#Anterior poliomyelitis# is the lesion underlying what was formerly known as infantile paralysis--a name to be avoided, because the condition is not confined to infants and it is not the only form of paralysis met with in young children. Anterior poliomyelitis is characterised by an illness attended with fever, in which the child is found to have lost the power of one, less frequently of both lower extremities; or, it may be, of one or both arms. After a period, varying from six weeks to three months, the paralysis tends to diminish both in extent and degree, and in the majority of cases it ultimately persists only in certain muscles or groups of muscles. At the onset of the paralysis the affected limb is helpless and relaxed, the reflexes are lost, the muscles waste, and those that are paralysed exhibit the reaction of degeneration. In severe cases, and especially if proper treatment is neglected, the nutrition of the limb is profoundly affected; its temperature is subnormal, the skin is bluish in cold weather and readily becomes the seat of pressure sores. In course of time the limb lags behind its fellow in growth, and tends to assume a deformed attitude, which at first can easily be corrected, but later becomes permanent.
When the acute stage of the illness is past, the chief question is to what extent recovery of function can be looked for in the paralysed muscles.
It would appear to be established that if a muscle reacts to faradism it will recover, but the contrary proposition does not follow. It was formerly accepted that a muscle which exhibits the reaction of degeneration is incapable of recovery, but observation has shown that this is not the case. Complete destruction of the motor cells in the anterior horn of grey matter as a result of poliomyelitis is now known to be exceptional; as a matter of fact, damage to the nerve cells is usually capable of being repaired. The muscles governed by these cells may appear to be completely paralysed, but with appropriate treatment their functional activity can be restored. As functional disability is frequently due to the affected muscle being over-stretched, it is of the first importance, when the acute symptoms are on the wane, that every care should be taken to prevent the weak muscular groups being put upon the stretch, and the greatest attention should be paid to the posture of the limb during convalescence. For example, if the child is allowed to lie with the wrist flexed, the flexor muscles undergo shortening, and the extensors are over-stretched and are therefore placed at a mechanical disadvantage. As the inflammatory changes in the anterior horn of the cord subside, the flexor tendons, from their position of advantage, are in a condition to respond to the first stimuli that come from their recovering motor cells, while the extensors are not in a position to do so. If, on the other hand, the wrist and fingers are maintained in the attitude of extreme dorsiflexion, the extensors become shortened, and, relieved of strain, they soon begin to respond to the stimuli sent them from the recovering nerve cells. Similarly in the lower extremity, when, for example, the muscles innervated through the peroneal (external popliteal) nerve are paralysed, if the foot is allowed to remain in the attitude of inversion with the heel drawn up--paralytic equino-varus--an attitude which is rendered more pronounced by the pressure of the bedclothes, the chance of the muscles recovering their function is seriously diminished. Another potent factor in preventing recovery, especially in the lower limbs, is erroneous deflection of the body weight. If, for example, there is weakness in the tibial group of muscles, and the child is allowed to walk, the eversion of the foot will steadily increase, the tibial muscles will be more and more stretched, the opposing peroneal muscles will shorten, and, in time, the bones of the tarsus will undergo structural alterations which will perpetuate the deformity. If, on the other hand, by some alteration of the boot, the foot is maintained in the attitude of inversion, the weakened or paralysed tibial muscles are placed in a much more favourable condition for recovery.
It must be emphasised that no operation should be performed in these cases until the question whether it be possible or not to restore the apparently paralysed muscle is settled. The clinical test of the recoverability of a muscle is to keep it for a long period--six or even twelve months--in a condition of relaxation. This test should be made, no matter how many months or years the muscle may have been paralysed.
The first stage in the treatment, therefore, is the correction of existing deformity, after which the limb should be kept immovable until the ligaments, muscles, and even the bones have regained their normal length and shape. The slightest stretching of a muscle which is in process of recovery disables it again.
The age of the patient influences the method of treatment. In young children in whom the structures are soft and yielding, gradual correction of the deformity is to be preferred to the more rapid methods employed in older children. The proper sequence consists in correcting the deformity, providing the simplest apparatus to keep the limb in good position, preventing erroneous deflection of body weight during walking, and then allowing the child to grow and develop until he has reached the age of five before considering such an operation as transplanting tendons, and the age of ten before deciding to ankylose a flail-like joint.
Reposition, Manipulations, Supports.--An attempt is made to correct the deformity by manipulation, and the proper attitude is maintained by a mechanical support. If the foot has become rotated so that the sole looks laterally, the medial side of the boot must be raised, and an iron worn which extends from the knee down the lateral side of the leg, to end, without a joint, in the heel of the boot. In pes equinus, the iron is let into the back of the heel and extends forwards into the waist of the boot, to keep the foot at right angles to the leg and to relax the weak extensor muscles.
Division of Contractions.--Bands of fascia and contracted tendons which prevent correction of deformity may have to be divided or lengthened. This is best done by the open method.
Removal of Skin.--To assist in maintaining the desired attitude, Jones recommends the plan of excising an area of the redundant skin on the weaker aspect of the limb; in equinus, the skin is taken from the dorsum; in equino-varus, from the front and lateral aspect of the foot. When the edges of the gap have united, the foot is maintained in the desired attitude for some months, even if parents carelessly remove the iron support to let the child run about.
Tendon transplantation, a procedure introduced by Nicoladoni, is to be considered in children of five and upwards. It may be employed for different purposes: (1) To reinforce a weak muscle by a healthy one--for example, by transplanting a hamstring tendon into the patella to reinforce a weak quadriceps, or reinforcing the weak invertors of the foot by a transplanted extensor hallucis longus. (2) Transplantation may also be performed to replace a muscle which is quite inactive and does not show any sign of recovery--for example, the tibiales being paralysed, the peroneus longus may be implanted into the navicular or first metatarsal to act as an invertor of the foot.
Wherever possible a tendon should be transplanted directly into bone, as, if it is attached to soft parts it rarely holds firmly enough. The bone should if possible be tunnelled, and the tendon passed through the tunnel and securely fixed. When bringing a tendon to its new point of attachment, it should pass in as straight a line as possible, avoiding any bend or angle which might impair its action. Fat is the best medium for the transplanted tendon to traverse, as it acts as a sheath and prevents the formation of adhesions which would interfere with the function of the new tendon. All deformity must be corrected before transferring the tendon; if the tendon is too short to admit of this, it can be lengthened by means of silk threads (Lange).
According to Jones, the most successful transplantations are the following, in order: (1) The tibialis anterior into the lateral tarsus in paralysis of the peronei; (2) the peroneus longus into the navicular in paralysis of the tibial group; (3) the extensor hallucis longus into any part of the foot where it may be wanted; (4) the hamstrings into the patella, to reinforce the quadriceps, provided the strictest after-treatment can be secured; (5) deflection of part of the tendo Achillis to one or other side of the foot.
Arthrodesis.--This operation, first performed by Albert in 1877, consists in removing the cartilage covering the articular surfaces of bones with the object of producing a firm ankylosis. The procedure is most successful in the ankle and mid-tarsal joints, and as a result of it there is obtained a secure and firm base of support in walking. Before performing arthrodesis, the surgeon must decide whether the patient will be better off with a stiff joint or with a weak and movable ankle supported by apparatus. This is often a matter of social position; in the poor, an ankylosed joint is more useful and less expensive. An arthrodesis should seldom be performed at the ankle until the child has passed his eighth year, or at the knee until he has reached his twentieth year. There is plenty to be done during the period of waiting, and if this is done well, it is possible that the operation may not be required. The existing deformities, for example, will have to be corrected, areas of skin removed to relieve functionless muscles of strain, the body weight appropriately deflected, and the child must be taught to walk with the aid of a support, swinging his limb about, and using it effectively in a correct position. Such exercise is a powerful agent in promoting physiological and functional development.
Nerve anastomosis, which seeks to provide a new channel for the transmission of motor impulses to the paralysed muscles, has as yet a restricted field of application--for example, the tibial and peroneal nerves may be anastomosed when the muscles supplied by one of them are paralysed. Stoffel of Heidelberg lays stress on regard being paid to the anatomical arrangement of the nerve bundles within the nerve-trunk so that motor fibres may be joined to motor ones and not to sensory. It is necessary also to cut across some of the fibres of the healthy nerve in order that they may grow into the nerve which is degenerated.
In extreme cases in which the limb is hopelessly paralysed and useless, it may be amputated to admit of an artificial limb being worn; it must be borne in mind, however, that such limbs furnish poor stumps, usually quite unable to bear pressure.
#Cerebral Palsies of Childhood--Spastic Paralysis.#--These may be due to arrest of development of the brain, to injuries of the head at birth, to meningeal haemorrhage, or to other lesions of the brain, with secondary degenerative changes in the spinal cord. The commonest cause is haemorrhage occurring during child-birth from the veins which ascend from the middle part of the convexity of the hemisphere to open into the superior sagittal (superior longitudinal) sinus. The blood is poured out beneath the dura on one or on both sides of the falx cerebri, and as it accumulates near the vertex, the damage to the motor centres for the legs is usually more extensive than that to the centres for the arms. The paralysis may affect one side of the body--hemiplegia, or both sides--diplegia; less commonly one extremity alone is involved--monoplegia. In diplegia, in which both arms and both legs are affected in the first instance, the arms may recover while the lower extremities remain in a spastic state, a condition known as Little's disease. The mental functions may be normal but more frequently they are imperfectly developed, the impairment in some cases amounting to idiocy. The affected limbs exhibit muscular rigidity or spasm, which is aggravated on movement but disappears under an anaesthetic; the reflexes are exaggerated, and sometimes there are perverted involuntary movements (athetosis). The growth of the limb is impaired, and contracture deformities may supervene (Fig. 131). The amount of power in the limb is often astonishing, in marked contrast to what is observed to follow upon anterior poliomyelitis. The degree of natural improvement is by no means great, and normal function is almost never regained.
The treatment is concerned in the first place with improving the condition of the muscles by methodical exercises and massage. When reflex irritability of the muscles with consequent spasm is a prominent feature, the reflex arc may be interrupted by resection of the posterior nerve roots corresponding to the part affected. This operation, first suggested by Spiller but chiefly popularised by Foerster, has yielded the best results in cases of Little's disease, in which there still remains a considerable amount of voluntary movement, and yet there is inability to walk on account of involuntary spasm. In the case of the lower extremities, three or more of the lumbar and one or more of the sacral nerve roots are resected within the vertebral canal. Sensation is diminished but not abolished in the area of skin involved. Massage and exercises and, it may be, splints or apparatus are essential factors in promoting the recovery of function. It has not yet been decided whether the results of the resection of nerve roots justify the risk.
Apart from Foerster's operation, or when it has failed, the spasm of any individual muscle or group of muscles may be got rid of by diminishing the nerve supply to the muscle or by lengthening the tendon. Diminishing the nerve supply was suggested by Stoffel; it consists in exposing the motor nerve as it enters the muscle and resecting one-third or one-half of the fibres so as to reduce the innervation to the required degree. The method is still on its trial.
Lengthening the Tendons.--In spastic paraplegia, for example, Jones resects the origins of the adductors longus and brevis, lengthens the tendo Achillis, divides the popliteal fascia and hamstrings, and transplants the biceps into the quadriceps; after which the limbs are put up in the attitude of wide abduction for six weeks. It is important that the patient should begin to walk with the legs wide apart and learn to balance himself without any feeling of insecurity; he should be taught to look at an object straight in front of him rather than on the ground.
THE LOWER EXTREMITY
CONGENITAL DISLOCATION OF THE HIP
This is the commonest of all congenital dislocations. Its frequency varies in different countries, being greater on the continent of Europe than in this country. It is more often unilateral than bilateral (about 4 to 1), and is about three times more common in girls than in boys.
The dislocation takes place in the early months of intra-uterine life, and may be associated with deficiency of the liquor amnii.
#Pathological Anatomy.#--In the infant, the anatomical changes in the joint are less marked than they are after the child has borne its weight on the limb. The acetabulum, never having been occupied by the head of the femur, is imperfectly developed; it remains flat and shallow, is partly filled with fibro-fatty tissue derived from the synovial membrane, and is always too small for the head of the femur. The cotyloid ligament being broader and thicker than usual, makes the osseous portion of the socket appear deeper than it really is. In unilateral cases the affected half of the pelvis is contracted, so that the pelvic basin is narrowed and oblique. The head of the femur is small, flattened, and, in some cases, conical; and the angle formed by the neck with the shaft is altered, sometimes diminished, it may be to a right angle--coxa vara (Fig. 129); sometimes increased--coxa valga. There is also a variable degree of torsion of the neck, ante-torsion being of practical importance as it increases the difficulty of retaining the head in the socket. The capsule is lax and admits of the head passing upwards for a variable distance on to the dorsum ilii. In unilateral cases the ligamentum teres is elongated and thickened; in bilateral cases it is frequently absent.
In children who have walked, the head of the femur is pushed farther upwards on the dorsum ilii; the capsule becomes lengthened by supporting the weight of the body. That part of the capsule which arises from the lower margin of the acetabulum stretches across the socket and partly shuts it off from the rest of the joint cavity. In course of time the capsule becomes greatly thickened, and may present an hour-glass constriction about its middle, which may prove a serious obstacle to reduction. The socket becomes small and triangular, and there is almost no ledge against which the head of the femur can rest. A superficial depression may form on the ilium where it is pressed upon by the head of the femur, covered by the capsule; and in the course of years, as the head changes its position, several secondary sockets may be formed. No proper new bony socket forms like that in traumatic dislocations that remain unreduced because in the congenital variety the thickened capsule intervenes between the head of the bone and the dorsum ilii. The displacement of the head is most frequently backwards (dorsal luxation), and as the point of support thus falls behind the acetabulum the pelvis tilts forwards, and the lumbar spine becomes unduly concave (lordosis). The muscles of the hip and thigh alter in consequence of the changed relations; the gemelli, obturators, and piriformis are lengthened, the adductors, hamstrings, and ilio-psoas are shortened, while the glutei and quadriceps are but little altered. In rare cases the head is displaced upwards and lies immediately above the acetabulum.
Clinical Features.--The condition rarely attracts attention until the child begins to walk, but sometimes the unusual breadth of the pelvis, the presence of a lump in the buttock, snapping about the hip, or a peculiar way of holding the limb, leads the parents to seek advice early. In unilateral cases, when the child has learned to walk at the late age of two, three, or it may even be four years, it is noticed that the back is hollow and the buttocks unduly prominent, and that there is a peculiar and characteristic limp; each time the weight of the body is put upon the affected limb, the trunk makes a sudden dip towards that side. There is no pain on walking. The affected limb is shortened, as is shown by the projection of the great trochanter above Nelaton's line; the shortening gradually increases, and in time may amount to several inches. It is partly compensated for by resting the affected limb on the balls of the toes and flexing the knee on the sound side. The gluteal fold is shorter, deeper, and higher than on the healthy side, and on account of the obliquity of the pelvis the spine shows a lateral curvature, with its concavity to the affected side. The movements at the hip-joint are free in all directions except abduction; on practising external rotation it is often found to be abnormally free; lastly, in young children, if the pelvis is fixed, the head of the bone may be made to glide up and down on the ilium.
In bilateral cases the trunk appears well grown in contrast to the short lower limbs, the hollow of the back is exaggerated, the abdomen protrudes, the perineum is broadened, and the buttocks are unduly prominent. The gait is waddling like that of a duck, the trunk lurching from one side to the other with each step. In untreated cases the deformity and disability become more pronounced as the capsular and round ligaments are further stretched, the shortening and limp become more marked, the patient is easily fatigued by walking or standing, and is usually unfitted for earning a living. We have had under observation, however, an adult male with bilateral dislocation and extroversion of the bladder, who efficiently performed the duties of a carrier for many years.
Except in fat infants, the diagnosis is not difficult; the absence of pain and tenderness, the freedom of motion and the absence of the head of the femur from its normal position, differentiate the condition from tuberculous disease of the joint, and from coxa vara and other deformities in the region of the hip. Trendelenburg's test consists in noting the relative level of the buttocks when the patient stands on the affected leg. Normally the buttocks remain on the same level when the patient stands on one leg; in congenital dislocation the buttock of the limb raised from the ground drops to a lower level; in coxa vara it rises higher.
In paralytic conditions at the hip there may be considerable resemblance to dislocation, but the muscles are slack and wasted, and the normal attitude can easily be restored by pulling on the limb. The most certain means of diagnosis is by the X-rays, which show the position of the head of the bone in relation to the acetabulum, and any torsion of the neck of the femur that may be present. This last point is determined by taking a series of skiagrams in different positions of the limb; these are also useful in correcting erroneous impressions as to the angle of the neck of the femur.
Treatment.--We are indebted to Paci, Schede, Calot, Lorenz, and Hoffa for the rational treatment which seeks to reduce the dislocation by manipulation.
#Reduction by Manipulation# (Method of Lorenz).--The child is anaesthetised and placed on its back with the legs over the end of the table. While an assistant steadies the pelvis, the surgeon pulls on the limb so as to bring the trochanter down to Nelaton's line; this is followed by forced rotation outwards and inwards and forcible abduction to a right angle, and by kneading the adductors till they are stretched and torn. The next step is to stretch the hamstrings, and this is done by raising the foot, without bending the knee, until the front of the thigh meets the abdomen, and the toes the face. To stretch the anterior muscles, the patient is turned on the side or face, and the hip is hyper-extended both in the straight and in the abducted position. The stage is now reached at which attempts at reduction may be made; the child is again laid on its back, the surgeon grasps the knee, flexes the thigh to a right angle, rotates laterally, and slowly flexes and abducts, while the thumb pushes from behind on the trochanter, trying to guide and lift it over the rim of the socket as the hip reaches the over-abducted position. Lorenz uses a wedge of wood padded with leather about 3 inches high to rest the trochanter upon while attempting to lift it forward. When reduction takes place, there is generally a sound and a sudden jump, as in reducing a traumatic dislocation.
To keep the head in the socket, the limb must be maintained in the position of right-angled abduction and external rotation (90 deg.) by a plaster case, which includes the lower part of the trunk and both limbs down to the knee. Under the plaster, stockinette drawers are worn, and the bony prominences are padded with cotton wool. The plaster should overlap the costal margin. The first case is worn for two months or more, and is then renewed at shorter intervals, the degree of abduction being diminished at each renewal until the limbs are nearly parallel. The child is only kept in bed for a week or two, and is then allowed up, being provided with a boot and high sole on the affected side, but should not use crutches. At the end of six months, by which time the capsule has become tightened up round the head of the femur, the plaster is given up and massage and exercises are employed.
In bilateral cases both dislocations are reduced at one sitting if possible, and a plaster case applied with both thighs abducted and flexed to a right angle, the so-called "frog position."
In the event of failure to reduce a dislocation at the first attempt, the limb should be fixed in plaster in the abducted attitude for ten days or a fortnight, and then another attempt made. The greatest number of successes in bilateral cases is met with under five years of age, and in unilateral cases under seven. Reduction may sometimes be accomplished, however, in older children.
If it is found impossible to restore the head of the femur to the acetabulum, an attempt should be made by similar manipulations to wedge it under the long head of the rectus femoris, or, failing this, below the anterior iliac spine under the sartorius and tensor fasciae femoris. By thus converting a posterior into an anterior dislocation, the tilting of the pelvis and the lordosis are greatly diminished. This procedure, named by Lorenz anterior transposition of the head of the femur, is specially applicable to cases in which relapse has taken place after reduction, and to those above the age when reduction should be attempted.
Reduction by open operation may be had recourse to in cases in which, after several attempts, reduction has failed, or in which re-dislocation has occurred; it is, however, a serious operation. Attempts have also been made by means of pegs and other contrivances to fix the head of the bone and prevent it sliding upwards on the ilium. When reduction is impossible by any means, a stiff leather jacket with prolongations around the thighs may diminish the deformity and improve the walking.
#Snapping Hip# (Hanche a ressort).--This is a rare affection, met with in children and young adults, and characterised by the occurrence of a sudden, snapping sound, sometimes attended with pain in the region of the great trochanter. This usually occurs when the limb is slightly flexed or adducted, and rotated either inwards or outwards. On palpation a cord-like structure may be felt, which slips forwards and backwards over the trochanter when the position of the limb is altered.
The condition was formerly described as a voluntary dislocation of the hip; it is now believed to be due to a cord-like band of tissue slipping backwards and forwards over the trochanter. The band is usually derived from the fascia lata, sometimes reinforced by the anterior fibres of the gluteus maximus, sometimes by the tensor fasciae femoris. The condition seldom gives rise to any appreciable disability and surgical treatment is rarely called for. In a number of cases the muscle has been fixed by sutures with satisfactory results. In a recent case, an extensive open dissection proved negative, but the stitching of the gluteus to the trochanter was followed by the disappearance of the snapping.
#Paralytic Deformities of the Hip.#--In anterior poliomyelitis the paralysis of muscles may be so widespread that the limb is unable to support the weight of the body, or certain groups of muscles only are paralysed and the child may be able to walk with the help of apparatus. Even if the ilio-psoas is paralysed, flexion is still possible by the anterior fibres of the gluteus medius, the anterior adductors, and when the leg is rotated out by the tensor fasciae and sartorius, the dislocation differs from the traumatic variety in that the head, although it leaves the socket, remains within the capsule. Dislocation tends to occur from the disturbance of muscular balance, anterior dislocation being commoner than posterior in about the proportion of two to one; the nature of the dislocation is best demonstrated by means of the X-rays. Reduction is rarely possible without an open operation. Tendon and nerve-transplantation are scarcely possible, and arthrodesis is rarely to be recommended; contracture deformities, however, are often benefited by tenotomy in young children, and in older children by osteotomy through the trochanter, and putting the limb up in the abducted position.
In spastic paralysis of cerebral origin, the tendency is towards contracture, usually in the attitude of flexion, with adduction and inversion. This may result in dislocation backwards on to the dorsum ilii, and may occur in patients confined to bed (Fig. 131).
#Contractures and Ankyloses of the Hip.#--Various forms of contracture are met with as a result of cicatricial contraction, or from shortening of the fasciae, muscles, and ligaments when the hip has been maintained in the flexed position for long periods--for example, in psoas abscess, chronic rheumatism, or hysteria. The majority, however, result from tuberculous disease of the hip-joint. In osseous ankylosis, an attempt may be made to restore movement by the operation of Murphy, which consists in chiselling through the osseous junction between the bones, deepening the acetabulum if necessary, and then interposing between the bony surfaces a portion of fat-bearing fascia derived from the fascia lata over the great trochanter. The operation of Jones consists in detaching the great trochanter (the insertions of the glutei into it being left intact), dividing the neck of the femur, and then securing the separated portion of the trochanter to the proximal end of the neck to prevent union of the fragments.
COXA VARA AND COXA VALGA
These deformities depend on abnormalities of the angle of the neck of the femur; the average or normal elevation is 125 deg. for the adult and 135 deg. for the child; variations between 120 deg. and 140 deg. are considered normal. If the angle is less than 120 deg. the condition is one of coxa vara; if greater than 140 deg., coxa valga. The angle of inclination of the neck of the femur is dependent upon the adjustment of certain forces, namely, the weight of the body, the action of muscles, and the resistance of the bone. The most obvious cause of deviation of the neck from the normal angle is some condition which causes softening of the bone so that it yields under weight-pressure, the most common being partial fractures, rickets, and other diseases of the bone.
#Coxa Vara--Incurvation of the Neck of the Femur.#--There may be a simple adduction bend of the neck, the head sinking to, or even below, the level of the great trochanter (Fig. 132); or this may be combined with a curve of the neck, of which the convexity is upwards and forwards, so that the lower border of the neck is greatly shortened and the head approximated to the lesser trochanter. At the same time the shaft of the femur is adducted and rotated outwards.
Adolescent Coxa Vara.--This, the most common clinical type, is met with in boys between the ages of twelve and eighteen. The unilateral form is nearly always the result of injury to the neck of the femur or to the epiphysial junction, although the deformity may not show itself for months or a year or two after the injury. The deformity may be the first indication, or it is preceded by pain and stiffness; the patient complains of being easily tired, of difficulty in kneeling and sitting, difficulty in riding, and of an increasing limp in walking. On examination, the limb is found to be shortened, the great trochanter is displaced upwards and backwards and is unduly prominent, and the muscles of the buttock and thigh are a little smaller and softer than on the normal side. The limb is adducted, its normal range of abduction, and sometimes also of flexion, is restricted, and there is, as a rule, some degree of lateral rotation, so that the toes point outwards. It should be noted that the same picture--shortening with eversion and stiffness at the hip--results from the common fracture of the neck of the bone in old people. The adduction element of the deformity is partly compensated for by upward tilting of the pelvis on the affected side and curvature of the spine with its concavity towards the affected limb.
When the condition is bilateral it is usually the result of disease in the bone, rickets most frequently in this country. The attitude and gait are highly characteristic, as the adducted and everted legs tend to cross each other at the knee, the deformity being of the scissors-like type (Fig. 134), and in extreme cases the patient is only able to walk with the aid of crutches.
Diagnosis.--Pain in the hip and a limp in walking suggest hip-joint disease, but while in coxa vara the movements are chiefly restricted in the direction of abduction, in hip disease they are restricted or absent in all directions. From congenital dislocation of the hip the diagnosis can usually be made by the history, the examination of the joint and of its movements; and by the Trendelenburg test (p. 252). In sacro-iliac disease, the pain and tenderness are over the sacro-iliac joint and the movements at the hip are free in all directions. Valuable evidence is obtained from skiagrams.
Treatment.--In the early stages, especially if there is pain and tenderness, the patient must lie up and extension is applied in the abducted position of the limb; after a fortnight or so recourse is had to massage and exercises and the patient is allowed up for a little each day, attention being paid to flat-foot, which is a common accompaniment. When deformity is the prominent feature and interferes with locomotion it must be corrected. The bloodless method is to be preferred; under general anaesthesia, the shortened adductors are stretched or divided, and forcible movements are carried out in all directions, until the limb can be brought into an attitude of marked abduction and internal rotation. A plaster-case is then applied, from the pelvis to the middle of the calf, the knee being slightly flexed for greater comfort; in a week or so the patient is able to go about, and in a couple of months a second plaster-case is applied, this time leaving the knee free. After another six weeks or so a moulded splint is used, which can be removed at bedtime. The traumatic forms can nearly always be corrected by this bloodless method. In advanced cases the deformity can only be corrected by open operation, which consists in dividing the femur obliquely downwards and medially through the great trochanter, and, the adductor muscles having been ruptured or divided, the limb is put up in the abducted position along with, if required, powerful weight extension.
In cases of traumatic origin--epiphysial separation--Sprengel has obtained good results by forcibly abducting and internally rotating the limb under an anaesthetic, and then applying a plaster-case which extends down to the knee.
#Other Forms of Coxa Vara.#--In rickety children, coxa vara is most often associated with pronounced eversion of both lower extremities, without the capacity for abduction being necessarily restricted, and with but little impairment of function. The child should be treated for rickets, and put up in a double long splint with the limbs abducted and inverted.
In arthritis deformans of the hip, it is not uncommon to have considerable depression of the head of the bone and diminution in the angle of its neck, with consequent restriction of abduction. Sometimes the upper end of the shaft is also curved.
In osteomyelitis fibrosa, involving the upper end of the femur, a gross form of coxa vara may be observed, of which a marked example is shown in figures on pp. 476, 478, Volume I.
The congenital variety of coxa vara is due to various intra-uterine conditions, of which the chief is defective development of the upper end of the femur; as it does not manifest itself until the child begins to walk, the resemblance to congenital dislocation of the hip is very close.
#Coxa Valga.#--Coxa valga is the reverse of coxa vara, the angle at the neck of the femur being over 140 deg.. It is not nearly so important in practice as coxa vara. It may result from incomplete fractures or epiphysial separations, rickets, or various forms of osteomyelitis, but it is also a frequent accompaniment of other deformities, such as congenital dislocation of the hip and paralysis following anterior poliomyelitis. It is commoner in boys than in girls, and is more often single than bilateral. The limb is lengthened, abducted, and rotated outwards; there is flattening of the buttock, and the trochanter is depressed so that it lies below Nelaton's line. The patient is unable to adduct the limb, and shows a peculiar gait, which has frequently caused the condition to be mistaken for unilateral congenital dislocation at the hip.
In recent cases it may be possible under anaesthesia forcibly to adduct the limb and rotate it inwards, and to retain it in this position with a plaster bandage. In advanced cases the length of the limbs may be equalised by a high sole on the sound side, or by performing an osteotomy through the great trochanter.
THE REGION OF THE KNEE
#Congenital dislocation# at the knee-joint is rare; it is usually incomplete, and the patella is sometimes absent. The dislocation may be permanent, or may only occur from accidental movements of the limb. In some cases it can be produced at will by the patient or the surgeon. We have observed one such case in a professional cyclist in whom this capacity of partially dislocating the knee entailed no disability. When the child begins to walk, an apparatus which will prevent hyper-extension and lateral motion should be fitted to the limb.
#Congenital absence of the patella# usually complicates other abnormalities of the knee-joint. The tubercle of the tibia is prominent and the extensor tendon unusually thick. In flexion the tendon rises on to the lateral condyle of the femur.
#Congenital Dislocation of the Patella Laterally.#--This may be persistent or intermittent. In the persistent form the dislocation is present from birth; the patella rests on the trochlear surface of the lateral condyle, and when the knee is flexed may pass farther outwards and become completely dislocated, lying against the lateral aspect of the condyle.
In the intermittent or recurrent form the patella lies in its normal place, but is liable to be displaced outwards when the joint is flexed; the displacement occurs suddenly and unexpectedly in walking, and the patient may fall to the ground, suffering intense pain. The knee-cap is readily replaced on extending the joint, but the sprain of the joint is followed by effusion, and the patient is usually disabled for a day or two. It is met with chiefly in girls, and there may be a history that the child was late in walking and learned with difficulty. On examination, the patella is found to have an abnormal range of movement outwards, although it cannot be completely dislocated without considerable pain. If the child is brought for advice when there is fluid in the joint, the condition is liable to be mistaken for tuberculous synovitis. The observation that the undue mobility of the knee-cap is present in both knees is of assistance in arriving at a diagnosis, and also the history that the girl has repeatedly hurt her knee in falling.
The cause of the abnormal mobility of the patella varies in different cases; in some there is congenital laxity of the ligaments, in others a faulty formation of the lower end of the femur. Bade has observed families in which several children were affected, and although there was nothing abnormal in the shape of the bones, the knee was slender and delicately formed.
The use of a strong knee-cap may prevent falling, but as a rule an operation is required, and there is quite a number to choose from, the principle of them all being to prevent displacement of the bone without unduly restricting flexion of the joint. That devised by Goldthwait consists in exposing, by means of a vertical incision, the whole length of the patellar ligament, splitting it longitudinally, separating the lateral half from the tibia, passing it under the medial portion and suturing it to the periosteum; this gives the quadriceps a straight line of pull. We have achieved the same result by dividing the lax capsule and synovial membrane on the medial side of the patella, and overlapping the edges with a double line of catgut sutures.
Lateral dislocation of the patella is met with in extreme forms of knock-knee, and after correction of this deformity by osteotomy, and its possible occurrence should be guarded against at the time of the operation.
#Genu Recurvatum.#--In this deformity the knee is hyper-extended, the thigh and leg forming an angle which is open forwards; the attitude may be permanent or may only appear on walking. It is an extremely disabling and unsightly deformity.
There are several varieties. In the congenital form, which is apparently due to a faulty attitude of the lower extremities in utero, the patella may be imperfectly developed or absent; the knee is convex backwards, and attempts to flex the joint cause pain. Other deformities frequently coexist. The treatment consists in flexing the joint to a right angle under an anaesthetic, and maintaining this attitude by means of plaster-of-Paris or splints until the growth of parts overcomes any tendency to relapse.
Acquired Forms.--The most common acquired form is the result of anterior poliomyelitis, and is described in the next section.
The deformity may also be due to rickets which has caused a backward bend of the tibia immediately below its upper epiphysis--sometimes combined with an exaggerated forward curve of the femur. If there is no prospect of spontaneous rectification, the upper end of the tibia should be divided with the osteotome, and the limb straightened.
It may result also from fracture or from separation of one of the epiphyses in the region of the knee, or from cicatricial contraction of the quadriceps. As a result of bone and joint disease, it is met with chiefly in neuro-arthropathies when the knee has become disorganised and flail-like.
#Deformities of the Knee resulting from Anterior Poliomyelitis and from Spastic Paralysis.#--When there is paralysis of all the muscles acting on the knee, the joint may be so flail-like that the patient is unable to stand without the aid of a crutch, or when weight is put on the limb, it assumes the attitude of genu recurvatum. The usefulness of the limb may be improved by the application of a rigid apparatus with a lock at the joint so that it can be used in the extended position for walking or in the flexed position for sitting. The rigid knee produced by arthrodesis affords good support but is inconvenient in sitting.
When the quadriceps alone is paralysed, the patient is obliged to maintain the joint in the position of extreme extension, because the least degree of flexion results in the limb giving way under him. In course of time the posterior ligament is stretched, and the joint becomes hyper-extended, acquiring the attitude of genu recurvatum. When it is bilateral the gait is seriously impaired. The treatment consists in applying an apparatus which prevents hyper-extension, in improving the condition of the thigh muscles, and in wearing a splint at night which secures the flexed position. Recourse may be had to operative measures, such as transplanting one of the hamstrings into the patella, so as to compensate for the loss of power in the quadriceps, arthrodesis, or supra-condylar osteotomy of the femur.
When the quadriceps is overcome by a contraction of the hamstrings, as in spastic paraplegia, the knee is fixed in the flexed position and the child is unable to walk. The flexion may be corrected by lengthening the hamstring tendons, bringing the divided biceps tendon through an opening in the vastus lateralis, and attaching it to the rectus and to the patella. If there is a combination of flexion and genu valgum, the knee-joint should be resected and ankylosed in the straight position.
#Contracture and Ankylosis at the Knee.#--In addition to the different paralytic forms above described, contracture may result from ulceration and suppuration in the popliteal space, and from disease (osteomyelitis) in one of the adjacent bones. The greater number of contractures and ankyloses are the result of disease in the joint, and have already been described.
GENU VALGUM AND GENU VARUM
In the normal limb, a line drawn from the centre of the head of the femur to a point midway between the malleoli passes through the centre of the knee-joint. If the line passes outside the centre of the knee-joint, the condition is one of genu valgum; if inside, it is one of genu varum (Fig. 135).
#Genu Valgum--Knock-knee.#--In this deformity the leg joins the thigh at an angle which is open outwards, and when the affection is bilateral, the projecting knees tend to knock against each other in walking; the term X-legs is sometimes applied to it.
Etiology.--The observations of Macewen and of Mikulicz, and information afforded by the Roentgen rays, have shown that the primary cause of the deformity is an inequality of growth at the ossifying junction of the femur or tibia or of both. This inequality of growth is nearly always due to rickets, and its direction is determined by a faulty attitude of the limbs in standing and walking. The legs being abducted, the weight of the body falls unequally on the medial and lateral parts of the ossifying junctions, and inequality of growth results.
Pathological Anatomy.--Examination of the femur usually shows that the lower third of the diaphysis is lengthened on its medial side and shortened on its lateral side, and that the epiphysis, itself unaltered, is fitted on to the diaphysis obliquely, so that the medial condyle appears to be increased in length and to occupy a level distinctly below that of the lateral condyle. In many cases the tibia shows corresponding alterations. On section of the bones, the epiphysial cartilage and the zone of ossification are found to be unduly broad and irregular.
The neck of the femur is shortened and its angle diminished. The bones of the leg are sometimes bent inwards in their lower thirds, and this compensates partly for the valgus deformity at the knee. The articular cartilage of the lateral condyle and the lateral meniscus are usually thickened. In pronounced cases the quadriceps tendon and the patella are displaced laterally, and this may be so pronounced that on flexion of the joint the patella is dislocated on to the lateral condyle of the femur. The biceps tendon and ilio-tibial band are shortened and more prominent as a result of the approximation of their attachments, and they are also displaced laterally. The sartorius and gracilis are displaced backwards, so that they descend behind instead of on the medial side of the knee. The popliteal artery lies on the back of the lateral condyle instead of in the hollow between the condyles, and the tibial (internal popliteal) nerve is displaced even farther outwards. The capsular and other ligaments are slack, so that the joint is unstable and easily hyper-extended. There is often some effusion into the joint.
Radiograms reveal the changes in the bones (Fig. 138); the shaft of the femur or tibia, or both, which may also be curved, is set obliquely on its epiphysis; and the clear zone, corresponding to the epiphysial cartilage, is uneven and broader than normal. There are also less obvious changes in the density of the shadow and in the arrangement of the trabecular structure of the bones.
Clinical Features.--In the infantile form (Fig. 139) the knock-knee is commonly associated with rickets in other parts of the skeleton, and especially with bending of the tibia and femur, and in extreme cases the child may be unable to walk.
The deformity is about as frequently bilateral as unilateral. There may be knock-knee on the one side and bow-knee on the other. If, as is usually the case, the deformity is due to obliquity of the femur, it disappears on flexing the joint (Fig. 140), because in flexion the tibia glides behind the projecting median condyle; if the deformity affects the tibia only, the influence of flexion in disguising it is not so marked. It is usually possible to hyper-extend the joint, and, in the extended position, to rotate the leg outwards to a greater extent than is normal. In unilateral knock-knee, the affected limb is a little shorter than its fellow, but the patient compensates for this by depressing the pelvis on the affected side.
Prognosis.--In children below the age of six, the bones naturally tend to straighten if the child is kept off its feet. After this age, there is no such prospect.
The treatment of knock-knee in children is directed towards curing the rickets and preventing the child from putting its feet to the ground. If it cannot have the services of a nurse and the use of a perambulator, a light padded splint is applied on the lateral side of the limb, extending from the iliac crest to 3 inches beyond the foot. The splint is fixed above and below by bandages, and the projecting knee is drawn towards it by a few turns of elastic webbing. A method specially applicable to hospital out-patients, is to straighten the limbs as far as possible under anaesthesia, and apply a plaster bandage; the bandage is renewed at intervals of three weeks until the deformity is corrected. Whatever plan is adopted, it must be persevered with for at least six months, until the rickety changes in the bones have been entirely recovered from.
If the child is approaching the age of five or six before it comes under treatment, or if the deformity does not yield to treatment by splints, it is better to straighten the limb by osteotomy.
In adolescent knock-knee the patient seeks advice because of the deformity or of pain after exertion, especially at the medial side of the epiphysial junctions, of being easily tired, and of incapacity for any occupation involving standing. The bones are coarse and badly formed, and there is frequently a spinous process projecting downwards from the medial side of the tibia about three finger-breadths below the joint.
When the deformity is bilateral, the patient abducts the thigh and rotates the limb outwards at the hip to disguise the deformity, and to allow the projecting knees to pass each other. He usually supinates or inverts the foot, with the object of bringing the whole length of the lateral border of the sole into contact with the ground. Flat-foot is exceptional. The boots are usually more worn along the lateral than along the medial border of the sole and heel.
No apparatus that allows of the patient walking is of any value. If the deformity is marked, there should be no hesitation in having recourse to operation by one or other of the various methods of osteotomy.
In severe cases it may be found that when the deformity is corrected by osteotomy, the patella shows a tendency to be dislocated laterally on flexion of the knee. This may be prevented by putting up the limb in the attitude of slight genu varum.
The most difficult cases to treat are those in which, owing to curving of the lower part of the shaft of the femur with the convexity forwards, the knee is permanently flexed and cannot be completely extended.
#Other forms of genu valgum# are relatively rare. There is a congenital form arising from faulty position of the limbs in utero; a traumatic form following fracture or epiphysial separation in the region of the knee; and a paralytic form, usually combined with flexion, in cases of spastic paralysis. Finally, genu valgum may be a result of various forms of osteomyelitis of the lower end of the femur, or of disease in the knee-joint, such as tuberculosis, arthritis deformans, or Charcot's disease.
#Genu Varum--Bow-knee.#--In this deformity, which is the converse of genu valgum, the leg joins the thigh at an angle which is open medially. It is almost invariably bilateral, is of rachitic origin, and is frequently associated with bow-legs (Fig. 141). The tibia takes a greater share in its production than the femur. Although an ungainly deformity, it is much less frequently the source of complaint than knock-knee, because it scarcely interferes with locomotion--as a matter of fact, the subjects of bow-knee, although short in stature, are unusually sturdy on their legs. An extreme example of the deformity is shown in Fig. 141.
Treatment is carried out on the same lines as in genu valgum.
#Rickety Deformities of the Bones of the Leg--Bow-leg.#--These deformities are common in children; are nearly always bilateral and symmetrical, and may be associated with knock-knee or bow-knee. They may occur before the child is able to walk, the bones bending in the attitude in which the limbs are habitually placed--over the nurse's knee, for example, or as they are crossed underneath the child in sitting. In children who are able to walk, the curve is due to the weight of the body acting on the softened bones. In either case, the bending may be increased by the traction of muscles, and sometimes by the occurrence of greenstick fracture. The most common deformity is a uniform curvature of the bones laterally and forwards, or a more acute bend in the lower thirds of their shafts. In some cases the chief curvature is forwards. The ungainliness in walking may be added to by flat-foot. Backward curving of the upper end of the tibia has been already described as one of the causes of genu recurvatum. The most extreme deformities are met with in rickety dwarfs.
Treatment.--Under the age of six, and particularly in children, who are actively growing, the bones will probably straighten if the child is treated for rickets and kept off his feet; well-padded lateral splints are applied as recommended for knock-knee, and these should be taken off at intervals for massage and douching. Above the age of six, the choice lies between osteoclasis and osteotomy. In performing osteotomy the bone is either simply divided or a segment is resected. The fibula can usually be forcibly straightened, but may require to be divided through a separate incision. In aggravated cases it may also be necessary to lengthen the tendo Achillis.
The deformities of the bones of the leg in inherited syphilis, ostitis deformans, and osteomalacia have already been described.
#Congenital Deficiencies of the Bones of the Leg.#--The tibia may be absent completely or in part, more often on one side than on both sides. In either case the leg is short and stunted, the knee is flexed, the foot occupies the position of extreme equino-varus, and the limb is useless. The extent of the defects is demonstrated by the Roentgen rays. Among other defects with which it may be associated, absence or deficient development of the patella is the most frequent. When the upper end of the tibia is absent, the fibula articulates with the lateral condyle of the femur. The operative treatment aims at correcting the flexion at the knee, the equino-varus deformity of the foot, and at substituting the fibula for the absent tibia. The deficiency of the upper end may be compensated for by implanting the head of the fibula between the condyles of the femur, and that at the lower end by splitting the fibula so as to form a socket for the talus. Amputation should be avoided, as even a dwarfed leg and foot improves the service of an artificial limb. A modification of the O'Connor extension boot may be employed.
The fibula may be absent completely or in part. The clinical appearances depend upon the condition of the tibia. When the tibia is normal, the most notable feature is the absence of the lateral malleolus, and the extreme valgus attitude of the foot. More commonly the tibia makes a sharp forward bend just below its middle, and the overlying skin presents a dimple or scar-like depression. This has usually been regarded as an evidence of intra-uterine fracture, but the observations of Hoffa suggest that both the bend of the bone and the depression on the skin are due to pressure exercised upon the leg from without by an amniotic band or adhesion. The leg fails to grow, the deformity becomes more pronounced, and the toes become pointed. If the tibia is markedly bent, it may be straightened by osteotomy; and the tendons, Achillis and peronei, may require to be lengthened. If the ankle is unstable as a result of the absence of the lateral malleolus, it may be artificially ankylosed, or the lower end of the tibia may be split vertically so as to make a socket for the talus. In either case, the foot is placed in the equinus attitude to compensate for the shortening of the leg. Deficiency of the tibia is frequently associated with imperfect development of the great toe; deficiency of the fibula with absence of the lateral toes and their metatarsal bones.
Volkmann's Supra-malleolar Deformity.--This condition, which is closely allied to that just described, consists in a congenital deficiency in the development of the bones of the leg, and especially of the fibula, as a result of which the articular surface is oblique and the foot deviates to one or other side. The foot usually occupies a valgus position, the sole looking laterally, and only its medial border coming into contact with the ground. It is treated by supra-malleolar osteotomy.
THE FOOT
Various deformities are met with in the region of the ankle and tarsus. The term "talipes" is commonly used to include all these, but here it will be restricted to that form in which the heel is more or less elevated, and the foot supinated so that it rests on its lateral border--talipes equino-varus. In pes equinus the foot is in the position of plantar-flexion, and the patient walks on the toes. In pes calcaneus the foot is dorsiflexed so that the tip of the heel comes in contact with the ground; this deformity may be combined with eversion of the foot, pes calcaneo-valgus, or with inversion, pes calcaneo-varus. When the instep is unduly arched, the terms pes cavus, pes arcuatus or hollow claw-foot are employed; while loss of the arch constitutes flat-foot, and eversion of the sole, pes valgus.
CLUB-FOOT
#Talipes Equino-varus.#--This deformity may be congenital or acquired.
#Congenital talipes equino-varus# (Fig. 142) is a common malformation which is sometimes associated with other deformities, such as hare-lip or spina bifida, and may be met with in several members of one family. It is nearly twice as common in boys as in girls, and is slightly more frequently bilateral than unilateral. Its etiology is obscure, and various hypotheses have been put forward to account for it, but no one is convincing. It may be pointed out, however, that the foetal foot is very easily moulded into abnormal attitudes by external pressure such as might be exercised by the wall of the uterus when the liquor amnii is deficient. In a number of cases there are indications of such pressure over the bony prominences of the foot, in the shape of circumscribed scar-like areas in which the skin is atrophied; and in the infant, the intra-uterine position can be reproduced, thus demonstrating its method of origin. The occurrence of club-foot in several generations is alleged to support the Mendelian law.
Pathological Anatomy.--In well-marked cases the foot presents a concavity towards the medial side, the maximum point of the curve being opposite the mid-tarsal joint. When the patient attempts to stand, only the lateral border of the foot touches the ground, and the weight is borne on the fifth metatarsal, the cuboid, and the greater process of the calcaneus.
The individual tarsal bones, especially the talus and calcaneus, are altered in shape as well as in their relations to one another and to the tibio-fibular socket. The navicular and cuboid are rotated medially around the anterior ends of the talus and calcaneus respectively, and the tubercle of the navicular comes to lie close to the medial malleolus. The lower third of the tibia is twisted medially on its vertical axis.
The changes in the soft parts follow the general law that tissues which are relaxed become shortened, while those that are put on the stretch are lengthened. All the tissues on the medial, concave side of the foot are shortened, the structures most affected being the medial and the posterior ligaments of the ankle, and the inferior calcaneo-navicular ligament. There is also shortening of the muscles inserted into the tendo Achillis, and to a less extent of the tibiales anterior and posterior. The extensor tendons on the dorsum are displaced medially.
Clinical Features.--In children who have not walked, the degree of deformity varies, sometimes being very slight; in pronounced cases, the foot is turned medially, and in that position forms a right angle with the leg; the sole looks backwards and the medial border upwards. The foot appears shortened because it is curved on itself, the heel is narrower and more vertical than normal, the medial malleolus is obscured by the approximation of the navicular, and the lateral malleolus is unduly prominent.
In extreme cases, the supinated foot forms an acute angle with the leg, and there is frequently a deep transverse depression across the sole, the result of contraction of the plantar fascia--a feature which is distinctive of the congenital form of club-foot.
In children who have walked, the deformity becomes aggravated. The dorsum of the foot is markedly uneven, partly because of the prominence of the individual tarsal bones, and especially of the head of the talus and greater process of the calcaneus, and partly because of a depression over the neck of the talus. Instead of resting on its lateral border, the foot may finally rest on the dorsum, the sole looking upwards and backwards. While the skin over the heel remains comparatively thin and delicate, that covering the lateral border and dorsum of the foot becomes the seat of callosities, beneath which adventitious bursae are formed. These bursae are liable to become inflamed, and are then a source of great suffering, and if they suppurate may cause persistent sinuses. The muscles of the leg and foot, although not paralysed, undergo atrophy from disuse. In walking, the patient lifts one foot over the other in an ungainly and laborious manner, without any spring, as if walking on stilts.
In adults, these features are further aggravated, and there are permanent changes in the bones (Fig. 144).
Treatment.--This should be commenced as soon as the viability of the infant is beyond question, as the younger the patient the more easily and completely is the deformity rectified. Manipulations to correct the deformity should be carried out twice or thrice daily, and the limbs are also massaged and douched. At the end of two or three months, assistance may be derived from the use of a simple lateral poroplastic or aluminium splint with a foot-piece, or more simply by a strip of rubber plaster. The foot is held in the over-corrected attitude and the plaster is applied so as to maintain this attitude. If this regime is systematically persevered with from within a few days after birth, by the time the child begins to walk the sole can be brought into contact with the ground, and the weight of the body will aid in correcting the deformity. If the equinus element resists correction, the tendo Achillis should be lengthened.
The turning in of the toes may be overcome by strapping the feet at night to a wooden board with the whole lower limb rotated laterally so that the toes of each foot point directly outwards. On account of the tendency towards relapse, the manipulations and massage must be persevered with for at least a year.
Tenotomy and Forcible Correction under Anaesthesia.--In more severe cases we have to deal not only with the contracted soft parts, but with changes in the bones resulting from their having grown in adaptation to the deformed attitude. The majority of surgeons defer operative measures until the child is about a year old.
The soft parts to be divided are the tendo Achillis, the medial and posterior ligaments of the ankle, the plantar fascia, the calcaneo-navicular ligaments, and the tibialis posterior tendon. The varus deformity may then be corrected by laying the foot on its lateral side on a padded triangular wooden block, and pressing forcibly on the anterior and posterior ends of the foot so as to undo the curve on its medial side and allow of abduction of the foot; this is usually attended with cracking as the shortened ligaments give way. The equinus element is next dealt with by forcibly dorsiflexing the foot until the deformity is over-corrected. If it is preferred to correct the deformity in stages instead of at one sitting, the equinus element is left to the last. In older children, the strength of the hands is usually insufficient to stretch the tissues, and mechanical wrenches may be employed, such as those devised by Thomas, Bradford, or Lorenz.
Resection of a wedge from the tarsus (Davies Colley, 1876) is reserved for the most severe cases in which the shape and rigidity of the bones prevent correction of the deformity by any other means. The base of the wedge is on the lateral aspect, and the bone removed includes parts of the calcaneus, cuboid, talus, and navicular.
Removal of the talus is an alternative operation to resection of the tarsus, and may yield equally good results.
In children, before the tarsal bones have become completely ossified, Ogston's method yields good results; instead of removing a wedge from the tarsus, the osseous nucleus of each bone is gouged out, leaving the cartilaginous shell. In this way the intertarsal joints are not interfered with, and the cartilaginous tarsus can be moulded so that when ossification is completed the bones differ but little from the normal.
After any of these operative procedures, manipulations, massage, exercises, electrical stimulation of the muscles, and the wearing of some apparatus must be persevered with for at least twelve months. Failures are due to not sufficiently over-correcting the deformity in the first instance, and to neglect of after-treatment; in hospital practice it is difficult to ensure continuous supervision over long periods.
Finally, amputation may be called for when other methods have failed, and the patient is unable to put the foot to the ground because of suppurating bursae and ulceration of the skin.
#Acquired Talipes Equino-varus.#--In the great majority of cases this condition results from anterior poliomyelitis. It especially affects the peronei and the extensors of the toes, and is unilateral. The patient is unable to dorsiflex and abduct the foot, which hangs with the toes pointed and the sole turned medially.
At first the joints are flaccid, and the attitude can easily be corrected by manipulation. In course of time, however, the opposing muscles--those inserted into the tendo Achillis, the tibialis posterior, and the long flexors of the toes--become shortened, and there is secondary contraction of the plantar fascia and of the ligaments on the medial side of the foot, and the deformity is thus rendered permanent. The bones also are altered in their shape and mutual relations, the talus being rotated forwards so that a large portion of its trochlear surface protrudes from the tibio-fibular socket. The skin is cold and livid, and readily suffers from pressure sores. The whole limb is ill-developed, and may be shorter than its fellow, and the paralysed muscles are wasted and exhibit for a time the reaction of degeneration.
A similar deformity may result from section of the peroneal (external popliteal) nerve, from the peroneal form of progressive muscular atrophy, and from peripheral neuritis.
The treatment of paralytic equino-varus, short of operation, has been referred to under anterior poliomyelitis (p. 242). If tendon transplantation is indicated, the tendon of the tibialis anterior is attached to the cuboid, and a strip of the tendo Achillis to the dorsal aspect of the tarsus. Jones displaces the tibialis anterior into the base of the fifth metatarsal.
If the paralysis is widely distributed, and the joints are flail-like, it is better to ankylose the ankle and mid-tarsal joints. It may be necessary to divide in several places the plantar fascia and other structures that have undergone secondary shortening.
As using the limb hastens the restoration of function, the child should be got on to his feet as soon as possible.
The spastic form of talipes equino-varus is comparatively rare. The plantar flexors and invertors distort the foot into the equino-varus attitude. The heel is drawn up, the anterior part of the foot is adducted and inverted at the mid-tarsal joint. The muscles are tense and rigid, and the reflexes exaggerated. The condition is frequently bilateral, and is often associated with other deformities of the lower limb and with a characteristic spastic gait. Considerable improvement may be brought about by lengthening the tendons of the shortened muscles. In severe cases it may be necessary to resect a portion of the tarsus.
The occurrence of #varus without equinus# is so exceptional as not to call for separate description.
#Pes Equinus.#--This deformity, in which the foot is in the position of plantar-flexion with the heel drawn up and the toes pointed, is nearly always acquired as a result either of poliomyelitis or of spastic paralysis. In typical cases the patient walks on the balls of the toes (Fig. 145). It is seldom met with as a congenital condition. Occasionally it is due to nerve lesions such as peripheral neuritis, or to injuries and diseases in the region of the ankle, when the foot has been allowed to remain for long periods in the attitude of plantar-flexion. In a limited number of cases the equinus attitude is assumed to compensate for shortening of the limb.
In poliomyelitis the deformity is most often unilateral (Fig. 146), while in spastic paralysis it is frequently bilateral (Fig. 145), and is usually accompanied by excessive arching of the foot--pes cavus--as a result of plantar-flexion at the mid-tarsal joint, and hyper-extension of the first phalanges and plantar-flexion of the second and third phalanges of the toes--"clawing of the toes."
Clinical Features.--In the mildest cases the patient is able to bring the foot to a right angle. In average cases the heel is raised off the ground, and the foot rests on the balls of the toes. In extreme cases, and especially when the extensors are completely paralysed, the toes may be flexed towards the sole, and the weight is borne on the dorsum of the foot (Fig. 146). The patient suffers from painful corns and callosities, and from inflammation of bursae which form over the points of pressure. When unilateral, the patient compensates for the lengthening of the limb by flexing the knee and throwing the limb outwards in walking. In severe cases, especially when both limbs are affected, the patient may be dependent on crutches.
The talus projects on the dorsum, the anterior part of its trochlear surface escapes from the tibio-fibular socket, and the calcaneus is drawn up so that it comes into contact with the bones of the leg (Fig. 147).
Shortening of the soft parts affects chiefly the muscles inserted into the tendo Achillis, the posterior ligament, and posterior parts of the lateral ligaments of the ankle. The fasciae, ligaments, and muscles of the sole of the foot are also shortened. The flexors of the toes, the tibialis posterior, and the peroneus longus are shortened to a less degree.
Treatment.--Of all the deformities of the foot, pes equinus is that most easily rectified. In recent cases a great deal may be done by regular manipulations, and by the wearing of some corrective splint or apparatus between times.
In well-marked cases it is necessary to lengthen the shortened structures, and especially the tendo Achillis. When the equinus is corrected, the excessive arching of the foot (pes cavus) and the clawing of the toes usually disappear, but it may be necessary to lengthen the flexor tendons, especially that of the great toe, and also the plantar fascia.
Jones divides the tendo Achillis and the flexors of the toes subcutaneously, and maintains the dorsiflexion by excising an oval flap of skin from the front of the ankle.
In aggravated cases, the bones must be attacked, for example by excising the talus. Arthrodesis of the ankle alone or along with the mid-tarsal joint may be indicated when these joints are flail-like. Amputation is reserved for cases which are otherwise hopeless, such as that shown in Fig. 147.
When the deformity is compensatory to shortening of the limb, it is usually said to be a mistake to correct the equinus. Experience shows, however, that in young patients growth is stimulated by walking on the limb after the deformity has been corrected; the sole of the boot is then raised to the necessary extent.
#Pes Calcaneus.#--In this deformity the foot is dorsiflexed at the ankle-joint. It is sometimes combined with eversion of the foot--pes calcaneo-valgus, or with inversion--pes calcaneo-varus.
Pes calcaneus may be congenital or acquired. In the congenital form the deformity is frequently bilateral. There is dorsiflexion at the ankle-joint, and if an attempt is made to flex the foot towards the sole, the extensor tendons stand out prominently. In marked cases the long axis of the calcaneus is vertical, the tendo Achillis lies in close contact with the tibia, and the hollows on either side of the tendon are absent. The peronei are displaced from their grooves, and may lie in front of the lateral malleolus.
Corrective manipulations are commenced within a few days after birth, and a malleable splint is worn between times. When the child begins to walk there is a natural tendency towards recovery. In severe cases it may be necessary to lengthen the contracted tendons--the extensor digitorum, the extensor hallucis, and, it may be also, the peroneus tertius and tibialis anterior; the tendo Achillis may require to be shortened.
In the acquired form, the appearances are different, because the anterior part of the foot is usually flexed towards the sole, thus disguising to a certain extent the dorsiflexion at the ankle. This form is nearly always due to poliomyelitis, but it may also result from accidental division of the tendo Achillis. The anterior part of the foot is flexed towards the sole by the contraction of the plantar fascia and short muscles of the sole, the balls of the toes are approximated to the heel, and a deep transverse groove is formed in the sole opposite the mid-tarsal joint. The deformity presents a combination of the hollow foot--pes cavus--with pes calcaneus, and resembles that of a Chinese lady's foot. The foot rests on the heel and on the balls of the great and little toes, the sole of the foot being so deeply hollowed that even the lateral border does not touch the ground.
In paralysis of the calf muscles alone, the tendons of the peronei or flexor digitorum longus may be divided and stitched to the calcaneus, to take the place of the tendo Achillis. If the calf muscles are not completely paralysed and the tendo Achillis is merely stretched, this tendon may be shortened by splitting it longitudinally and making the ends overlap, or its insertion may be displaced downwards. When the ankle is flail-like, it may be necessary to perform arthrodesis.
Jones gets rid of the cavus deformity by resecting a wedge with its base towards the dorsum from the middle of the tarsus; the foot is then placed in a position of extreme calcaneus, the dorsum coming into contact with the front of the leg. Four weeks later a wedge is taken from the posterior part of the talus large enough to bring the foot down to a right angle with the leg; the articular surfaces of the tibia and fibula being denuded of cartilage, ankylosis takes place in a good position.
#Pes Calcaneo-valgus.#--This deformity, which consists in a combination of dorsiflexion at the ankle and eversion of the foot, is as common as pure calcaneus (Figs. 148 and 149); the heel is depressed, the sole looks laterally, and its medial border is convex. Although it may be congenital, it is usually acquired as a result of poliomyelitis. The calf muscles are paralysed while the peronei retain their power, and, along with the tibialis anterior and the extensors of the toes, become secondarily contracted. Treatment is conducted on the same lines as in pes calcaneus, and the valgus may be controlled by implanting the peroneus brevis into the navicular.
#Pes Calcaneo-varus.#--In this rare deformity the heel is depressed and the sole of the foot looks inwards.
#Pes Cavus.#--In this deformity, which is known also as hollow claw-foot, pes arcuatus, or pes excavatus, the longitudinal arch of the foot is exaggerated as a result of the approximation of the balls of the toes to the heel (Fig. 150). It is most frequently met with as an addition to pes equinus or pes calcaneus of paralytic origin, and has already been described. There is a mild form which is congenital, and which is quite independent of paralysis; another variety occurs in diseases of the spinal cord, such as Friedreich's ataxia.
The name hollow claw-foot appropriately indicates the clinical appearances. The arch is exaggerated and the instep abnormally high; there is hyper-extension of the toes at the metatarso-phalangeal joints, and plantar-flexion at the inter-phalangeal joints; the plantar fascia and muscles are shortened. The footprint shows that neither border of the foot touches the ground. The patient complains of pain in the instep, of painful corns over the heads of the metatarsal bones, and of difficulty in getting properly fitting boots.
Treatment should first be directed towards the equinus or calcaneus element of the deformity, for if these are corrected the cavus condition tends to disappear. Exercises and massage should be persevered with, and boots without heels should be worn. The contracted structures in the sole may require to be divided, either subcutaneously or by the open method, as a preliminary to forcible correction, and the hallucis tendon may be brought through the head of the first metatarsal. In aggravated cases the talus and the heads of the metatarsal bones may be excised.
FLAT-FOOT--PES PLANUS AND PES VALGUS
Flat-foot or splay-foot is that deformity in which there is loss of the arch, and the foot tends to be pronated and abducted. The term pes planus is applicable when there is merely loss of the arch; pes valgus when the foot is pronated and the sole looks laterally. Of all deformities of the foot, flat-foot is the one for which advice is most frequently sought; it is also a common complication of other disabilities of the foot and of the lower extremity. It is usually bilateral, and is about twice as common in the male as in the female. Various types are met with; they are known according to their cause, as static, congenital, traumatic, paralytic, rachitic, rheumatic, arthritic, gonorrhoeal, and tabetic.
#Static or Adolescent Flat-foot.#--This, by far the most common and important variety (Fig. 152), generally develops between the ages of fourteen and twenty. It is called static because the essential factor in its production is a disproportion between the weight of the body and the supporting power of the arch of the foot.
It is met with in rapidly growing children or adolescents of feeble muscular development and with long narrow feet, and those especially who, after leaving school, begin some occupation which entails much standing--such as that of a factory hand, message boy, or domestic servant. To enable him to stand with the least effort for long periods, the patient adopts an attitude which makes little demand on the muscles, and throws nearly all the strain of the body weight on the ligaments and bones of the feet. This, which has been called "the attitude of rest," consists in standing with the limbs apart, the knees slightly flexed, the legs slightly rotated laterally at the knee, and the feet pronated, with the toes pointing laterally. The most important local factors predisposing to flat-foot are weakness of those muscles which normally support the ankle and the tarsal arches, especially the tibiales; weakness of the ligaments of the foot; and softness of the tarsal bones. When these conditions are present and a faulty method of standing and walking is adopted, the undue strain to which the tendons and ligaments are exposed results in their being stretched; the bones are altered in position, and flat-foot results. The head of the talus is displaced medially, and is protruded between the calcaneus and navicular, tending to separate them from one another, stretching the inferior calcaneo-navicular ligament and causing the anterior part of the foot to be abducted. The plantar ligaments--especially the inferior calcaneo-navicular--are stretched and lengthened. In something like 80 per cent. there is the combined deformity--pes plano-valgus--in those who apply for treatment.
Clinical Features.--The patient complains of being easily tired, and of pain in the foot after walking or standing. There is generally more pain before the appearance of the deformity than when it has developed, and at this stage it is not so easily recognised, and is apt to be called "rheumatism." The most common seat of pain is at the medial border of the foot behind the tubercle of the navicular, and this is due to stretching of the inferior calcaneo-navicular ligament. Pain is also complained of in the middle of the dorsum across the instep, from stretching of the interosseous ligaments. Later, there is pain over the greater process of the calcaneus in front of the lateral malleolus, from these bones coming into contact. There may be nocturnal cramp in the muscles of the leg and foot.
The faulty attitude of the foot in standing and walking is usually evident. The foot appears longer and broader than normal, and when the body weight is put on it, it spreads out with the toes extended until the entire sole is in contact with the ground. In advanced cases, the medial border of the foot may be actually convex. Below and in front of the prominent medial malleolus, the head of the talus forms a rounded eminence, and a little farther forwards and lower still is the projection of the tubercle of the navicular. The eversion of the foot as a whole is best seen from behind; if the central axis of the leg is prolonged downwards, it approaches the medial border of the heel instead of passing through its centre; or, stated differently, instead of the axis of the calcaneus being a continuation of that of the leg, it deviates laterally and the medial malleolus is abnormally prominent. When the eversion is more pronounced, the sole looks laterally and the tendons of the peronei stand out in relief. The anterior part of the foot is displaced laterally. Flat-foot is frequently associated with stiff great toe; the patient having lost the power of dorsiflexing the toe, the first phalanx and first metatarsal are in a straight line, instead of forming an angle open towards the dorsum.
The muscles of the leg are flabby and poorly developed. When the patient is seated and asked to move the foot in different directions, there is a characteristic stiffness, ungainliness, and restriction in the range of movement. The feet are usually cold and sweat excessively. The gait is slouching, and there is a want of spring and elasticity. The lengthening of the foot results in the tendons, especially the flexors, being too short, hence hammer-like contraction of the toes may be brought about. The boots, after being worn, show a bulging of the instep towards the sole, greater wearing away of the sole along the medial border, and, when there is stiff great toe, an absence of the transverse crease on the dorsum opposite the balls of the toes. Footprints may be obtained by wetting the soles of the feet. The print of a normal foot shows only the heel, the lateral border of the foot, and the balls and tips of the toes. In flat-foot the medial border appears in the print to a greater or less extent (Fig. 154). If a record is wanted to estimate the progress of treatment, the sole of the foot is painted with a 5 per cent. solution of ferro-cyanide of potassium, and the patient stands on paper painted with the liquor of the perchloride of iron diluted one-half; the print appears dark blue on a yellow ground.
Skiagrams are useful for showing displacement of bones and differences between sitting and standing, and for recording the results of treatment.
Prophylaxis of Flat-foot.--Stress is to be laid on a supervised training of the whole muscular system, and especially of that of the legs. In walking and standing, the feet should be kept parallel and not pointed outwards, as was formally taught in schools of gymnastics and insisted upon by drill instructors. Children should be taught to walk properly, rising on the balls of the toes with each foot in succession. Attention should also be directed to the boots, which should be so fashioned that the medial side of the boot is kept straight and the end of the boot is opposite the big toe.
Treatment.--This is directed towards restoring and maintaining the arch of the foot. As the measures adopted necessarily vary with the extent to which the condition has progressed, it is convenient for purposes of treatment to recognise the following four degrees. A first degree, in which the arch reappears when the weight is taken off the foot or the patient rises on the balls of the toes; a second, in which the normal attitude can be restored by manipulation; a third, in which this is only possible under anaesthesia; a fourth, in which the bones are so displaced and altered in shape that correction is impossible without operation.
Cases of the First Degree.--If there is marked pain and tenderness, the patient must lie up. The general health is improved by a nourishing diet and by cod-liver oil and tonics; and the legs and feet are douched and massaged thrice daily. When pain and tenderness have disappeared, the patient is instructed how to walk and exercise the feet. In walking, the medial edges of the feet should be parallel with one another, first the heel should touch the ground and then the balls of the toes. He should neither stand nor walk long enough to cause fatigue, and in standing he should alter the attitude of the feet from time to time, and occasionally rise on the balls of the toes. The following exercises, devised by Ellis of Gloucester, should be practised: (1) Rising on the balls of the toes, the toes being directed straight forwards; (2) rising on the balls of the toes, with the points of the great toes touching each other, and the heels directed out, so that the medial borders of the feet meet in front at a right angle; (3) in the same attitude, after rising on to the balls of the toes, the knees are flexed and then extended before the heels descend again; (4) while seated in a chair, one leg crossed over the other, circumduction movements of the foot are carried out; (5) while standing, the medial border of the foot is raised off the ground several times, then the patient walks to and fro on the lateral border of the foot, and in the same attitude lifts one foot over the other. These exercises should be carried out slowly and deliberately, with the feet bare, and they should be carefully supervised until the patient thoroughly understands what is aimed at. The movements should be performed a definite number of times at regular intervals, but should not be pushed so as to cause pain or fatigue. The patient should be fitted with well-made lacing boots, with the heel and sole raised about half an inch on the medial side so that the foot rests mainly on its lateral border. The additional leather, which can be applied by any bootmaker, is in the form of a wedge, with its base to the medial side, one on the sole and one on the heel. The wedge fades away towards the lateral border, and also forwards towards the tip. In time, the limbs are further strengthened by sea-bathing, cycling, skipping, and other exercises.
In cases of the second degree, the patient should be provided with a metal plate inside the boot. That known as Whitman's spring is the most popular. A plaster cast is taken of the sole while the foot is held in its proper position, and on this a metal plate, preferably of aluminium bronze, is modelled. This is covered with leather and inserted into the boot. We have found the supports devised by Scholl simple and efficient. The treatment described for cases of the first degree is carried out in addition.
In cases of the third degree, the deformity is corrected under an anaesthetic. The foot is forcibly moved in all directions so as to stretch the shortened ligaments and to break down adhesions, it is then rotated into an extreme varus position, and fixed in plaster-of-Paris or to a Dupuytren's splint. It may be necessary to have recourse to the Thomas' wrench, employed in the correction of club-foot. When the reaction consequent upon this procedure has subsided, the question of shortening or of reinforcing the tendons concerned in the support of the arch of the foot may be considered; one of the peronei, for example, may be attached to the tubercle of the navicular. We have not found it necessary to employ this procedure.
In cases of the fourth degree, in which the displacement and alterations in shape of the bones constitute an insuperable bar to correction, operative treatment may be considered, either resection of a wedge including the talo-navicular joint or forward displacement of the tuberosity of the calcaneus.
#Spasmodic Flat-foot.#--There are cases of flat-foot in which pain and spasm of the peronei muscles are the predominant features. If the spasm is not allayed by rest in bed and hot fomentations, the foot should be inverted under an anaesthetic; and in this position it is encased in plaster-of-Paris. Jones resects an inch of each of the peroneal tendons about 2-1/2 inches above the tip of the lateral malleolus; Armour and Dunn claim to have obtained better results from crushing the peroneal nerve in the substance of the peroneus longus.
#Paralytic Flat-foot# (Fig. 155).--In typical cases this results from poliomyelitis affecting the tibial muscles. When other groups of muscles are affected at the same time, compound deformities, such as pes calcaneo-valgus, are more likely to result.
In paralytic valgus the medial border of the foot is depressed and convex towards the sole, and although the foot can readily be restored to the normal position by manipulation, it at once resumes the valgus attitude. The leg is wasted, the skin is cold and livid, and the ankle is flail-like. The treatment consists in reinforcing the paralysed tibial muscles by attaching the peronei, or a strip of the tendo Achillis, to the scaphoid, or in bringing about an ankylosis of the joints above and in front of the talus.
#Traumatic flat-foot# is that form which results directly from injury. It is most often due to a fall from a height on to the feet; the ligaments supporting the arch are ruptured, and the bones are displaced, either at the time of the injury or later when the patient gets out of bed. The arch can only be restored by a wedge-resection of the tarsus. Loss of the arch may follow as a result of walking on the everted foot after injuries about the ankle, especially a badly united Pott's fracture; the foot may be displaced laterally and pronated, the sole looking laterally. This variety is very unsightly and disabling; it is treated by supra-malleolar osteotomy of the tibia and fibula.
#Other Forms of Flat-foot.#--Flat-foot is sometimes met with in rickety children, in association with knock-knee or curvature of the bones of the leg, and is treated on the same lines as other rickety deformities. It may follow upon an attack of acute rheumatism or upon diseases in the region of the ankle and tarsus, such as gonorrhoea, arthritis deformans, tuberculosis, and Charcot's disease; the gonorrhoeal flat-foot is extremely resistant to treatment. There is a congenital form in which the sole is convex and the dorsum concave, the result of the persistence of an abnormal attitude of the foetus in utero. Lastly, there is a racial variety, chiefly met with in the negro and in Jews, which is inherited and developmental, and which, although unsightly, is rarely a cause of disability.
#Pes Transverso-planus.#--Lange describes under this head a sinking or flattening of the anterior arch formed by the heads of the metatarsal bones, of which normally only the heads of the first and fifth rest on the ground. In this condition all may be on the same level or the arch is actually convex towards the sole. It may coexist along with the common form of flat-foot, or it may be associated with the neuralgic pain known as metatarsalgia.
#Painful Affections of the Heel.#--These include inflammation of the bursa between the posterior aspect of the calcaneus and the lower end of the tendo Achillis, inflammation of the tendon itself and its sheath of cellular tissue, and the presence of a spur of bone projecting from the plantar aspect of the tuberosity of the calcaneus. The spur of bone is the source of considerable pain on standing and walking, and tenderness is elicited on making pressure on the plantar aspect of the heel; it is well demonstrated by the X-rays (Fig. 156). The condition is usually bilateral. Complete relief is obtained by removing the spur by operation.
Sever of Boston calls attention to a painful condition of the heel met with in children, and associated with changes in the epiphysial junction, allied to those met with in the epiphysis of the tubercle of the tibia in Schlatter's disease. The changes in the epiphysial junction can be demonstrated in skiagrams. Treatment is conducted on the same lines as in teno-synovitis of the tendo Achillis.
#Metatarsalgia.#--This affection, which was first described by Morton of Philadelphia (1876), is a neuralgia on the area of the anterior metatarsal arch, specially located in the region of the heads of the third and fourth metatarsal bones. It is most often met with in adults between thirty and forty, is commoner in women than in men, and is often combined with flat-foot. The patient complains of a dull aching or of intense cramp-like pain in the anterior part of the foot. The pain is usually relieved by rest and by taking off the boot. It may be excited by pressing the heads of the metatarsals together or by grasping the fourth metatarso-phalangeal joint between the finger and thumb. In advanced cases the pain may be so severe as to cripple the patient, so that she is obliged to use a crutch. On examination, the sole may be found to be broadened across the balls of the toes, and there may be corns over the heads of the third and fourth metatarsals. Skiagrams may show a downward displacement of the head of one or other of these bones, and prints of the foot may show an increased area of contact in the region of the balls of the toes. The affection is of insidious development, and is usually ascribed to sinking of the transverse arch of the foot--pes transverso-planus--the result of weakness or of wearing badly fitting boots. The intense pain is believed to be due to stretching of, or pressure upon, the interdigital nerves or the communicating branch between the medial and lateral plantar nerves; Whitman believes it is due to abnormal side pressure on the depressed articulations.
Treatment.--Great improvement usually results from treating coexisting flat-foot, and pain is relieved by rest, massage, and douching. A tight bandage or strip of plaster applied round the instep before putting on the stocking may relieve pain. Boots should be made from a plaster cast of the foot, high and narrow at the instep so as to compress the bases of the metatarsals, and with the medial edge of the sole and heel slightly raised; a support may be worn in the sole, like that used for flat-foot, with both the longitudinal and transverse arches exaggerated. Scholl has devised a support for the anterior arch which we have used with benefit. When the head of one of the metatarsals is displaced, it may be removed through a dorsal incision running parallel with the tendon of the long extensor.
#Hallux Valgus and Bunion.#--Hallux valgus is that deformity in which the great toe deviates towards the middle line of the foot and comes to lie on the top of, or beneath, the second toe (Figs. 155, 157). The head of the first metatarsal projects on the medial border of the foot, and, as a result of the pressure of the boot, an adventitious bursa is formed, which, when thickened by chronic inflammation, constitutes a prominent swelling or bunion. It is a common affection in civilised and especially in urban communities, and reaches its acme of development in adult women. It may occur on one or on both sides, and is sometimes associated with flat-foot.
The deformity develops slowly, and is usually attributed to the wearing of stockings which are unduly tight at the toes, and of improperly made boots. The boot that favours the occurrence of hallux valgus is one which is too short and has pointed toes, with the apex in the middle line of the foot instead of being in line with the great toe. The pressure of the boot displaces the great toe into the valgus position, especially if a high heel is worn, as the toes are then driven forward into the apex of the boot. Once the great toe is abducted by the pressure of the boot, the deformity is increased by bearing unduly on the medial side of the ball of the great toe, and by pointing the foot outwards in walking.
Arthritis deformans is rarely the cause of hallux valgus, but the changes characteristic of that affection are commonly present in the joint of the great toe. In pronounced cases, the base of the first phalanx is displaced on to the lateral aspect of the head of the first metatarsal, the exposed head of which frequently shows fibrillation and wearing away of the cartilage, and is often surrounded by new bone, sometimes amounting to an exostosis. There are also fringes from the synovial membrane that may be caught between the articular surfaces. The distal end of the first metatarsal is displaced medially, broadening the tread of the foot, and in severe cases its shaft is rotated on its long axis, so that its dorsal surface looks medially; the great toe is then similarly rotated (Fig. 157). The flexor and extensor tendons and the sesamoid bones are displaced laterally. The ligaments and other soft parts on the medial side are elongated, while those on the lateral side are contracted.
In women, the chief complaint may be of the disfigurement of the boot; in others, of pain and disability resulting from the sensitiveness of the joint and of the enlarged bursa over the head of the first metatarsal. The inflamed bursa, which sometimes communicates with the joint, may suppurate, and the infection may spread to the joint.
The treatment varies with the severity of the deformity. In mild cases, a great deal can be done by wearing properly made boots and stockings with a separate compartment for the great toe, or a pad of cotton wool or tent of rubber between the great and second toes. The patient should practise manipulations and exercises of the toes and feet, and putting the foot to the ground properly in walking. In pronounced cases, the pain and tenderness must first be got rid of by rest and soothing applications. At night, the attitude of the toe may be corrected by a moulded splint fixed to the medial aspect of the foot by strips of plaster; the toe is then bandaged to the distal end of the splint. Scholl has devised a prop, made of rubber, to be worn between the great and second toes. If there is flat-foot, this must receive appropriate treatment.
In aggravated cases, the deformity can only be corrected by an operation which consists in resecting the head of the metatarsal bone, and the tendon of the long extensor may be detached from its insertion and secured to the medial side of the first phalanx. A bar may be placed across the sole just behind the balls of the toes, and the boot should also comply with the anatomical shape of the foot.
#Hallux Varus or Pigeon-toe# (Fig. 158).--In this deformity, which is extremely rare, the great toe deviates from the middle line of the foot; it occurs chiefly in children in conjunction with other deformities, and interferes with the wearing of boots. Treatment consists in straightening the toe and retaining it in position by a splint or plaster of Paris. The medial collateral ligament and the tendon of the abductor hallucis may require to be divided.
#Hallux Rigidus and Hallux Flexus# (Fig. 159).--These terms indicate two stages of an affection of the metatarso-phalangeal joint of the great toe, first described by Davies Colley. In the earlier stage--hallux rigidus--the toe is stiff and incapable of being dorsiflexed, although plantar-flexion is, as a rule, but little restricted. When the joint, in addition to being stiff, is painful, sensitive, and swollen, the term hallux dolorosus is applied.
As the disease progresses, the toe is drawn towards the sole and becomes permanently flexed--hallux flexus--and any attempt at dorsiflexion is attended with pain.
The condition is met with chiefly in adolescent males, is nearly always associated with flat-foot, and is then usually bilateral. The patient's gait, in addition to having the characteristic features associated with flat-foot, is peculiarly wooden and inelastic, as instead of rising on the balls of the toes with each step, he puts down and lifts the sole as if it were a rigid plate. The pain is increased by walking. The boot tends to become worn away at the point of the toes and at the posterior edge of the heel, and the usual crease across the dorsum is absent.
On dissection it is found, especially in hallux flexus, that the inferior portions of the collateral ligaments are contracted, and that the cartilage of that part of the head of the metatarsal which is exposed on the dorsum is converted into fibrous tissue; there may also be other changes characteristic of arthritis deformans. Bony ankylosis has not been observed.
Treatment.--In early cases, great benefit results from measures directed towards the cure of the accompanying flat-foot, and especially the wearing of the support of the anterior arch devised by Scholl. If the joint of the big toe is painful and sensitive, absolute rest should be enforced until these symptoms have disappeared. The patient must wear a properly shaped boot with a pliable sole, and be instructed how to manipulate and exercise the toe. Later, when the toe is already rigid or flexed towards the sole, the above treatment is not feasible. It is then best to correct the deformity either by wrenching the toe into the dorsiflexed position, under anaesthesia, and fixing it with a plaster-of-Paris bandage; or, when this is impossible, by excising the articular end of the metatarsal bone and interposing a layer of fatty or bursal tissue between the distal end of the metatarsal and the base of the first phalanx. When these measures are impracticable, the suffering may be relieved by inserting in the boot a rigid metal plate which will prevent any attempt at dorsiflexion in walking.
#Hammer-toe.#--This is a flexion-contracture which generally involves the second, but sometimes also other toes. It may be congenital and inherited, but usually develops about puberty, and is then, as a rule, bilateral, and often associated with flat-foot.
The first phalanx is dorsiflexed, and the second is plantar-flexed, while the third varies in its attitude, sometimes being in line with the second (Fig. 160), sometimes even more plantar-flexed, and sometimes dorsiflexed. When the second toe alone is affected, as is commonly the case, it is partly buried by those on either side of it, only the knuckle of the first inter-phalangeal joint projecting above the level of the other toes (Fig. 160). The skin over the head of the first phalanx being pressed upon by the boot usually presents a corn, under which a bursa forms (Fig. 161). Both the corn and the bursa are subject to attacks of inflammation, which cause suffering and disability in walking. The soft parts at the distal extremity of the toe are flattened out by contact with the sole of the boot--hence the supposed resemblance to the head of a hammer.
On dissection, it is found that the contracture is maintained by shortening of the plantar portions of the collateral ligaments of the first inter-phalangeal joint and of the glenoid ligament upon which the head of the first phalanx rests.
Hammer-toe is usually ascribed to the use of tight socks and of ill-fitting boots, especially those which are median-pointed and are too short for the feet, but in some persons there appears to be an inherited predisposition to the deformity.
While corrective manipulations, strapping, and the use of splints may be of service in slight cases, it is usually necessary to perform an operation in order to extend the toe permanently. Before operating, any infective condition, such as a suppurating corn or bursa, must be corrected. The collateral and glenoid ligaments are divided subcutaneously--Spitzy also divides the flexor tendons and capsule--and if the toe can then be straightened, the foot is secured to a metal splint moulded to the sole and provided with longitudinal slots opposite the intervals on either side of the toe affected. The toe is drawn down to the splint by passing a loop of cotton or elastic bandage round the toe and through the slots. In many cases the contraction of all the tissues on the plantar aspect, including the skin, prevents the toe being straightened even after division of the ligaments, and it is then necessary to remove the head and neck of the first phalanx through a lateral incision. This is more satisfactory than amputation of the affected toe at the metatarso-phalangeal joint, as after this the adjacent toes tend to fall together and favour hallux valgus. If amputation is performed, a pad of cotton wool or rubber prop should be worn to fill up the vacant space.
The term Gampsodactyly has been applied to a deformity in which all the toes assume the position of hammer-toe, usually from a spastic condition of the muscles controlling the toes.
#Hypertrophy of the Toes.#--One or more of the toes may be the seat of hypertrophy or local giantism. This is usually present at birth or appears in early childhood, and may form part of an overgrowth involving the entire lower extremity (Fig. 162). The overgrowth may involve all the tissues equally, or the subcutaneous fat may be specially affected. The medial toes are those most commonly hypertrophied. In addition to being enlarged, the toe may be displaced from its normal axis. The hypertrophy may affect two or more toes which are fused together or webbed (Fig. 162). The treatment consists in amputating as much of the toe as will allow of an ordinary boot being worn.
#Supernumerary Toes# (Polydactylism).--These vary from mere appendages of skin to fully developed toes (Fig. 163); if they interfere with the wearing of boots they should be removed.
#Webbing of the Toes# (Syndactylism).--This may affect two or more toes, which may be united merely by a web of skin, or so completely fused that the individual digits are only indicated by the nails; the degree of fusion is shown by means of skiagrams. Unless associated with congenital hypertrophy, no treatment is called for.
THE UPPER EXTREMITY
#Congenital Absence of the Clavicle.#--Both clavicles may be absent, and it is possible for the patient voluntarily to bring his shoulders into contact with one another in front of the chest; there is little or no impairment of function.
#Displacements of the Scapula.#--Congenital Elevation of the Scapula (Sprengel's shoulder, 1891).--This abnormality is rare, and is not usually recognised till several years after birth. In one variety there is a bridge of bone or fibrous tissue connecting the superior angle of the scapula with the spinous process of one of the cervical vertebrae, and there may be a false joint at one end of the bridge permitting a certain amount of movement of the scapula. Associated abnormalities in the vertebrae and in the ribs are shown in skiagrams. In the more common type, the scapula seems to be held in its elevated position by shortening of the muscles attached to its body, and it is often rotated so that its lower angle is close to the spine and its axillary border nearly horizontal, or the axillary border may lie in close to the ribs, and the vertebral border project from the chest wall. The shoulder is generally higher and farther forward on the affected side, and there is a moderate degree of scoliosis. There is a want of purchase in the movements of the shoulder and upper arm.
When the deformity is bilateral, which is rare, the neck is short and thick, the chin lies close to the sternum, and the arms can scarcely be raised to the horizontal.
Gymnastic exercises and the wearing of a brace to hold the shoulders back and down may be followed by some improvement, but, as a rule, it is necessary to mobilise the scapula by operation. An X-ray photograph should first be taken, because, when the scapula is connected with the spine by a bridge of bone, this must be resected. The muscles attached to the vertebral border and spine of the scapula are divided, the bone is drawn down to its proper position, and the parts are fixed by plaster bandages.
Winged Scapula.--This condition consists in a marked displacement backwards of the lower angle and vertebral border of the scapula, when the patient attempts to raise the arm from the side (Fig. 165). Under normal conditions, in making this movement the serratus and rhomboid muscles pull forward the vertebral border and inferior angle of the scapula, and so fix the bone firmly against the chest wall. When these muscles are paralysed, as a result of anterior poliomyelitis, neuritis, or injury of the long thoracic nerve of Bell, or of the fifth and sixth cervical nerve-roots through which they receive their supply, the patient is unable to abduct the arm, and the deltoid having lost its point d'appui, its contraction merely results in tilting the angle of the scapula backward (Fig. 165).
Treatment.--In the majority of recent cases the condition yields to the administration of strychnin and other muscle and nerve tonics, and the use of massage and the faradic current. The application of a carefully adjusted padded belt is sometimes useful. The method of treatment by stitching the latissimus dorsi over the lower angle of the scapula is based on the erroneous assumption that the displacement is due to the slipping of that muscle off the bone; at the same time, it must be admitted that the operation sometimes diminishes the deformity and adds to the patient's comfort.
A more efficient method consists in detaching the clavicular portion of the pectoralis major from its insertion, and stitching it to the serratus anterior so as to make it take on the function of this muscle, or stitching it to the axillary border of the scapula. Success has also followed suture of the vertebral border of the scapula to the subjacent ribs (Eiselsberg).
Displacement of the scapula upwards and laterally has been observed as a result of partial paralysis of the trapezius when the nerves supplying it have been divided in removing tuberculous glands from the neck. In these acquired displacements, treatment is directed towards the nerve lesion and towards the improvement of the muscles by electricity, massage, and exercises; when the paralysis of the trapezius is permanent, the disability is gradually overcome by the compensatory hypertrophy of the levator muscle.
#Congenital Dislocation of the Shoulder.#--This rare condition is usually bilateral, and is associated with other congenital defects. The glenoid cavity is deformed or absent, and the dislocation may be sub-coracoid, sub-acromial, or sub-spinous. The movements of the arm are restricted, and the development of the extremity as a whole is imperfect. It is sometimes possible to reduce the dislocation by manipulation, or, if this fails, by operation. Unilateral dislocation is sometimes mistaken for dislocation that has occurred during delivery and vice versa.
#Habitual Dislocation# is described on p. 65.
#Paralytic Deformities--Paralytic Dislocation of the Shoulder.#--The muscles in the region of the shoulder may have their innervation interfered with as a result of various conditions, of which poliomyelitis and injuries of the brachial plexus at birth are the most important. The capsular ligament of the shoulder-joint, being no longer kept tense by the scapular muscles--especially the deltoid and lateral rotators--becomes relaxed, and is gradually stretched by the weight of the arm. The appearances are characteristic; the muscles of the shoulder are wasted, the acromion is prominent, and between it and the upper end of the humerus there is a marked hollow into which one or more fingers may be inserted. The arm hangs flaccid by the side, rotated medially and pronated, and moves in a flail-like fashion in all directions, the patient having little control over it. The best results are obtained by the transplantation of muscles, the trapezius being detached from the clavicle and stitched to the surface of the deltoid, and the upper arm fixed in the position of horizontal abduction with the arm rotated laterally and supinated. Bradford inserts a portion of the trapezius into the humeral insertion of the deltoid. When these methods are impracticable, the upper arm may be fixed to the trunk by some form of apparatus, or arthrodesis is performed so that the movements of the scapula are communicated to the upper arm; the best attitude for ankylosis is one of abduction with medial rotation, so that the hand can be brought to the mouth.
In cases of poliomyelitis, when all the muscles governing the elbow are paralysed while the muscles of the hand have escaped, it may be of great service to fix this joint permanently at rather less than a right angle. This may be effected by arthrodesis, or by removing an extensive diamond-shaped portion of skin from the flexor aspect of the joint and bringing the raw surfaces together, commencing the stitching at the lateral apices of the gap.
#Congenital Dislocations at the Elbow.#--The head of the radius may be dislocated forwards, backwards, or laterally--usually in association with imperfect development of the radius and of the lateral condyle of the humerus. When the displaced head of the bone interferes with supination, or with extension, it should be removed. Congenital dislocation of both bones of the forearm is extremely rare.
#Cubitus Valgus# and #Cubitus Varus#.--When the normal arm hangs by the side with the palm of the hand directed forward, the forearm and upper arm form an angle which is open outwards--known as the "carrying angle"; it is usually more marked in women in association with the greater breadth of the pelvis and the relative narrowness of the shoulders. When this angle is increased, the attitude is described as one of cubitus valgus. This deformity may be acquired as a result of rickets, but more commonly it is due to fracture of the lateral condyle of the humerus, in which the separated fragment has been displaced upwards.
Cubitus varus is the reverse of cubitus valgus. It is more common, is always pathological, and is nearly always a result of fracture of the lower end of the humerus or separation of the lower humeral epiphysis and subsequent interference with growth. These deformities may be corrected by supra-condylar osteotomy of the humerus.
#Synostosis of the superior radio-ulnar joint# is a rare congenital condition, in which the hinge movements at the elbow are free, but supination is impossible; an attempt may be made by operation to form a new joint.
#Volkmann's ischaemic contracture# of the muscles of the forearm, resulting in the production of claw-hand, is described in Volume I., p. 415.
#Deformities of the Forearm and Hand.#--The radius may be absent completely or in part, frequently in combination with other malformations. The most evident result is a deviation of the hand to the radial side--one variety of club-hand. The forearm is shortened, the ulna thickened and often bent, and the thumb and its metacarpal bone are often absent, so that the usefulness of the hand and arm is greatly impaired (Fig. 171). For this condition Bardenheuer devised an operation which consists in splitting the lower end of the ulna longitudinally and inserting the proximal bones of the carpus into the cleft.
Congenital deficiency of the ulna is extremely rare.
#Intra-uterine amputation# by constriction of amniotic bands sometimes occurs (Figs. 168, 169).
#Drop Wrist from Anterior Poliomyelitis.#--In this condition the capacity of extending the fingers is deficient or absent. Recovery can be confidently predicted if, on still further flexing the fingers, they can be voluntarily extended towards the point from which they are flexed (Tubby and Jones). Considerable improvement may result from fixing the hand by means of a splint in the attitude of dorsal flexion. The splint is removed at frequent intervals to allow of massage and other treatment being carried out, and it has usually to be worn for a period of one to two years. In some cases recourse should be had to arthrodesis.
In spastic paralysis the most pronounced deformity is flexion of the forearm and pronation and flexion of the hand (Fig. 166). Gradual extension at the wrist may be brought about by the use of a malleable splint, in which the angle is gradually increased, over a period of at least twelve months. Failing success by this method, operation may be had recourse to, and this consists in lengthening of tendons, and tendon transplantation. Tubby has devised an operation for converting the pronator radii teres into a supinator, and Robert Jones another in which the flexors of the carpus are made to take the place of the extensors. "These operations, combined if necessary with elongation of the flexors of the fingers, pave the way for diminution of the angle of flexion at the elbow, lessening of the pronator spasm, increase of the supinating power, reduction of the carpal flexion, and addition to the extensor power at the wrist" (Tubby and Jones).
#Congenital Club-hand.#--This rare deformity corresponds to congenital club-foot, and probably arises in the same way. The hand and fingers are rigidly flexed to the ulnar or radial side, so that the patient is incapable of moving them. Treatment is carried out on the same lines as for club-foot.
A deformity resembling this, acquired club-hand, is brought about when the growth of either of the bones of the forearm has been arrested as a result of disease or of traumatic separation of its lower epiphysis. The hand deviates to the side on which the growth has been arrested--manus valga or vara. The treatment consists in resecting a portion of the longer bone.
#Madelung's Deformity of the Wrist.#--In 1878, Madelung called attention to a deformity also called sub-luxation of the hand, in which the lower articular surface of the radius is rotated so that it looks towards the palm; there is palmar displacement of the carpus, and the lower end of the ulna projects on the dorsum. The cause of the condition is obscure, but it is met with chiefly in young women with slack ligaments, whose laborious occupation or athletic pursuits subject the hand and wrist to long-continued or repeated strain. It is as frequently unilateral as bilateral and may recur in successive generations. There is a good deal of pain, the grasping power of the hand is impaired, and dorsiflexion is considerably restricted. The deformity disappears on forcible traction, but at once reappears when the traction is removed. A wristlet of poroplastic or leather extending from the mid-forearm to the knuckles is moulded to the limb in the corrected position, and is taken off at intervals for massage and exercises.
When operative treatment is called for, it takes the form of osteotomy of the radius and ulna about an inch or more above their articular surfaces.
#Congenital dislocation of the wrist# is rare.
#Deformities of the Fingers.#--Various forms of congenital dislocation of the fingers are met with, but they are of little clinical importance, as they interfere but slightly with the usefulness of the digit affected.
Congenital lateral deviation of the phalanges is more unsightly than disabling; it is met with chiefly in the thumb, in which the terminal phalanx deviates to the radial or to the ulnar side in extension; the deviation disappears on flexion.
Congenital contraction of the fingers is comparatively common. It is an inherited deformity, and is often met with in several members of the same family. It most frequently affects the little or the ring and little fingers (Fig. 172), and is usually bilateral. The second and third phalanges are flexed towards the palm; the first phalanx is dorsiflexed, this being the reverse of what is observed in Dupuytren's contraction. Duncan Fitzwilliams suggests that it should be called "hook-finger," and that it is probably due to imperfect development of the anterior ligament of the first inter-phalangeal joint. He has observed it in association with laxity of the ligaments of the other joints of the body.
The affection is usually disregarded in infancy and childhood as being of no importance. In young children, the deformity is corrected by wearing a light splint fixed with strips of plaster, or a piece of whalebone or steel inside the finger of a glove. In older children, the finger may be straightened by subcutaneous division of the ligament over the palmar aspect of the base of the middle phalanx, or failing this by lengthening the flexor tendons and resecting a wedge from the dorsal aspect of the first phalanx close to the inter-phalangeal joint.
#Dupuytren's Contraction.#--This is an acquired deformity resulting from contraction of the palmar fascia and its digital prolongations (Fig. 173). It is rare in childhood and youth, but is common after middle life, especially in men. It is often hereditary, and is said to occur in those who are liable to gout and to arthritis deformans. While it is met with in the working-classes and attributed to the pressure of some hard object on the palm of the hand--such as a hammer or shovel or whip--its greater frequency in those who do no manual work, and the fact that it is very often bilateral, indicate that the constitutional factor is the more important in its causation.
In the initial stage there is a localised induration in the palm opposite the metacarpo-phalangeal joint, and the skin over it is puckered and closely adherent to the underlying fascia. After a variable interval, the finger is gradually and progressively flexed at the metacarpo-phalangeal joint. The ring finger is usually the first to be affected, less often the fifth, although both are commonly involved. It is rarest of all in the index. The flexion may be confined to the metacarpo-phalangeal joint, or the middle and distal phalanges may also be flexed; and as the deformity becomes more pronounced, the nail of the affected finger may come into contact with the skin of the palm. Dissections show that the flexion of the finger is the result of a chronic interstitial overgrowth or fibrositis and subsequent contraction of the palmar fascia and of its prolongations on to the sides of the fingers. The digital processes of the fascia are thickened and shortened, and come to stand out like the string of a bow. The adipose tissue in the skin of the palm disappears, and the skin and fascia thus brought into contact become fused. The tendons and their sheaths are not implicated; they are found lying deeply in the concavity of the curve of the flexed digit. There is no pain, but the grasp of the hand is interfered with, the patient is unable to wear an ordinary glove, and he may be incapacitated from following his occupation.
The condition is easily diagnosed from congenital contraction by the fact that in the latter the proximal phalanx is dorsiflexed.
Treatment.--When seen in the initial stage, contraction may be prevented by passive movements of the finger and by massage of the indurated fascia; we have observed cases in which these measures have held the malady in check for many years, but when flexion has already occurred, they are useless, and according to the social position, habits, or occupation of the patient, the condition is left alone or the deformity is corrected by operation.
Adam's operation consists in multiple subcutaneous division of the contracted fascia in the palm and of its prolongations on to the finger; in addition to dividing the fascia, the tenotomy knife should be used also to separate the skin from the fascia. The finger is then forcibly extended, and a well-padded splint secured to the hand and forearm. The skin on the palmar aspect opposite the first inter-phalangeal joint may give way when the finger is extended; should this occur, the resulting gap may be covered by a skin graft.
After healing has occurred, massage and movements must be persevered with, and a splint (Fig. 174) worn at night, as there is an inveterate tendency to recurrence of the contraction. In view of this tendency there is much to be said in favour of the radical operation which consists in removal of the fascia by open dissection. Owing to the long time required for healing and the sensitiveness of the scar, the results of excision of the fascia are sometimes disappointing. Greig has obtained good results by resecting the head of the metacarpal bone. When the little finger is completely flexed towards the palm it may be amputated, as it is always in the way.
#Supernumerary Fingers (Polydactylism).#--These may coexist with supernumerary toes, and the condition is often met with in several members of the same family. Sometimes the extra finger is represented by a mere skin appendage, the nature of which may only be indicated by the presence of a rudimentary nail; sometimes it contains bone representing one or more phalanges, or it may be fully formed (Fig. 175). In the majority of cases the superfluous finger should be removed.
#Congenital Deficiencies in the Number of Fingers.#--One or more fingers may be absent, such deficiency being often associated with imperfect development of the radius or ulna; or they may be represented by short rounded stumps, which are ascribed to the strangulation of the digits by amniotic bands in utero--the so-called intra-uterine amputation.
#Webbing of Fingers (Syndactylism).#--Congenital webbing or fusion of the fingers may be associated with polydactylism or with congenital hypertrophy, and, like other digital deformities, may affect several members of the same family. The degree of fusion ranges from a web of skin joining the fingers to a fusion of the bones, the latter being well seen in skiagrams. If an operation is decided upon, it should not be performed until the age of five or six years. In the simplest cases it is only necessary to divide the web and to unite the cut edges of skin along each finger by sutures, a skin graft being inserted into the angle between the fingers. An operation in which the skin is dissected up in the form of flaps may be required, but it should not be lightly entered upon, as in young children it has been known to be followed by gangrene of one or more of the digits.
#Congenital Hypertrophy of the Fingers.#--This is a form of local giantism affecting one or more digits, and involving all the tissues. The finger is usually of abnormal size at birth, and continues to grow more rapidly than the others, and it may also come to deviate from its normal axis. Such a finger should be trimmed down or removed, to permit of the use of the other digits.
#Trigger Finger# (Fig. 176).--This is an acquired condition in which movement of a finger or thumb, either in flexion or extension, is arrested, and is only completed with the assistance of the other hand. The obstacle to movement is usually overcome with a jerk or snap suggesting a resemblance to the trigger of a gun or the blade of a clasp-knife. The commonest cause is a disproportion between the size of the tendon and its sheath, such as may result from a localised thickening of the tendon. Recovery usually takes place under massage and passive movements. Failing this, the thickened portion of the tendon is pared down to its normal size; if it is the sheath of the tendon that is narrow, it is laid freely open.
#Drop# or #mallet finger# is described on p. 121.
XI. THE SCALP
Surgical Anatomy--Injuries: Contusion; Haematoma; Cephal-haematoma; Wounds; Avulsion--Diseases: Infective conditions; Cystic and solid tumours; Air-containing swellings; Vascular tumours.
#Surgical Anatomy.#--The skin of the scalp is intimately united to the epicranial aponeurosis by a network of firm fibrous tissue containing some granular fat, and representing the subcutaneous connective tissue. These three layers constitute the scalp proper, and they are so closely connected as to form a single structure which can be moved to a certain extent by the action of the epicranius muscle. The epicranius (occipito-frontalis) muscle with its aponeurosis extends from the superciliary ridge in front to the superior nuchal (curved) line of the occipital bone behind, and laterally to the level of the zygoma where it blends with the temporal fascia. Between the scalp proper and the pericranium is a quantity of loose areolar tissue, in the meshes of which extravasated blood or inflammatory products can rapidly spread over a wide area. Blood extravasated under the pericranium is limited by the attachments of this membrane at the sutures.
The blood supply of the frontal region is derived from the internal carotid arteries through their supra-orbital branches; the remainder of the scalp is supplied from the external carotids through their temporal, posterior auricular and occipital branches. The vessels, which run in the subcutaneous tissue, superficial to the epicranial aponeurosis, anastomose freely with one another and across the middle line. The main branches run towards the vertex, and incisions should, as far as possible, be directed parallel with them.
The venous return is through the frontal, temporal, and occipital veins. These have free communications, through the emissary veins, with the intra-cranial sinuses, and by these routes infective conditions of the scalp may readily be transmitted to the interior of the skull. The most important of the emissary veins are: the mastoid, condyloid, and occipital, passing to the transverse (lateral) sinus; the parietal, which enters the superior sagittal (longitudinal) sinus; and a branch from the nose which traverses the foramen caecum and enters the anterior end of the superior sagittal sinus.
The supra-trochlear, supra-orbital and auriculo-temporal branches of the trigeminal nerve, together with the greater and lesser occipital nerves, supply the scalp with sensation, while the muscles are supplied from the facial nerve.
The lymph vessels pass to the parotid, occipital, mastoid, and submaxillary groups of glands, the different areas of drainage being ill-defined.
INJURIES OF THE SCALP
#Subcutaneous Injuries.#--In simple contusion of the superficial layers, owing to the density of the tissues, the blood effused is small in quantity and remains confined to the area directly injured, which is firm and tender to the touch, swollen and discoloured. The disappearance of the swelling may be hastened by elastic pressure and massage.
Haematoma of the scalp results when lacerated vessels bleed into the sub-aponeurotic space. Owing to the laxity of the connective tissue in this area, the effused blood tends to diffuse itself widely, and, according to the position assumed by the patient, gravitates to the region of the eyebrow, the occiput, or the zygoma. When a large artery is torn the swelling may pulsate. A haematoma of the scalp may readily be mistaken for a depressed fracture of the skull, owing to the fact that the margins of the effusion are often raised and of a firm resistant character. A differential diagnosis can usually be made by observing that the swelling is on a higher level than the rest of the skull; that the raised margin can to a large extent be dispersed by making firm, steady pressure over it with the finger; and that, on doing so, the smooth and intact surface of the skull can be recognised. When a fracture exists, the finger sinks into the depression and the irregular edge of the bone can be felt. In doubtful cases, if cerebral symptoms are present, an exploratory incision should be made.
Even a large haematoma is usually completely absorbed, but the dispersion of the clot may be hastened by massage and elastic pressure. Any excoriation or wound of the skin must be disinfected.
Sometimes a blood-cyst, consisting of a connective-tissue capsule filled with a yellowish-red fluid, remains, and may require to be emptied with a hollow needle.
These effusions are to be distinguished from the cephal-haematoma, in which the blood collects between the pericranium and the bone. This is oftenest seen in newly born children as a result of pressure on the head during delivery, and is characterised by its limitation to one particular bone--usually the parietal--the further spread of the blood being checked by the attachment of the pericranium at the sutures. Occasionally a permanent thickening of the edges of the bone remains after the absorption of the extravasated blood. This condition is to be diagnosed from traumatic cephal-hydrocele (p. 390).
#Wounds of the Scalp.#--So long as a scalp wound, however extensive, is kept free from infection, it involves comparatively little risk, but the introduction of organisms to even the most trivial wound is fraught with danger, on account of the ease and rapidity with which the infection may spread along the emissary veins to the meninges and intra-cranial sinuses.
The deeper the wound, the greater is the risk. If the epicranial aponeurosis is divided, the "dangerous area" between it and the pericranium is opened, and if infection occurs, it may lead to widespread suppuration. Should the wound extend through the pericranium, infection is more liable to spread to the bone and to the cranial contents.
The usual varieties of wounds--incised, punctured, contused, and lacerated--are met with in the scalp, and they vary in degree from a simple superficial cut to complete avulsion. For medico-legal purposes it is important to bear in mind that a scalp wound produced by the stroke of a blunt weapon, such as a stick or baton, may closely simulate a wound made with a cutting instrument.
On account of the density of the integument and its close connection with the aponeurosis, scalp wounds do not gape unless the epicranial aponeurosis is widely divided. This facilitates union in incised wounds, but interferes with drainage in the long narrow tracts which result from punctures, and which are so liable to be infected and to implicate the sub-aponeurotic space, the pericranium, or even the bone. It also favours the inclusion in the wound of a foreign body, such as the broken point of a knife, or a piece of glass. The bleeding from scalp wounds is often profuse and difficult to control, because the vessels, fixed as they are in the dense subcutaneous tissue, cannot retract and contract so as to bring about the natural arrest of haemorrhage, and it is difficult to apply forceps or ligatures to their cut ends, suture ligatures are more efficient. On account of the free arterial anastomosis in the deeper layers of the integument, large flaps of scalp will survive when replaced, even if badly bruised and torn, and it is never advisable to cut away any un-infected portion of the scalp, however badly it may be lacerated or however narrow may be the pedicle which unites it to the head.
Gun-shot wounds of the scalp are usually associated with damage to the skull and brain. A spent shot, however, may pierce the scalp, and then, glancing off the bone, lodge in the soft parts.
Complete Avulsion.--In women, the scalp is sometimes torn from the cranium as a result of the hair being caught in revolving machinery. The portion removed, as a rule, consists of integument and aponeurosis with portions of muscle attached. In a few cases the pericranium also has been torn away. So long as any attachment to the intact scalp remains, the parts should be replaced, and, if asepsis is maintained, a satisfactory result may be hoped for. When the scalp is entirely separated, recourse must be had to skin-grafting.
Treatment of recent Scalp Wounds.--To ensure asepsis, the hair should be shaved from the area around the wound, and the part then purified. Gross dirt ground into the edges of lacerated wounds is best removed by paring with scissors. Undermined flaps must be further opened up and drained--by counter-openings if necessary. When there is reason to suspect their presence, foreign bodies should be sought for. Bleeding is arrested by forci-pressure or by ligature; when, as is often the case, these measures fail, the haemorrhage may be controlled by passing a needle threaded with catgut through the scalp so as to include the bleeding vessel. The wound is stitched with horse-hair or silk, and, except in very small and superficial wounds, it is best to allow for drainage. With the use of iodine as a disinfectant, it is often advantageous to dispense with dressings altogether.
#Complications of Scalp Wounds.#--The most common complications are those due to infection, which not only aggravates the local condition, but is apt to lead to spreading cellulitis, osteomyelitis, meningitis, or inflammation of the intra-cranial sinuses. These dangerous sequelae are liable to follow infection of any scalp wound, but more especially such as implicate the sub-aponeurotic area, or the pericranium. In the integument, a small localised abscess, attended with pain and oedema of surrounding parts, may form. Pus forming under the aponeurosis is liable to spread widely, pointing above the eyebrow, in the occipital region, or in the line of the zygoma. Suppuration under the pericranium tends to be limited by the inter-sutural attachments of the membrane. Necrosis of the outer table, or even of the whole thickness of the skull, may follow, although it is by no means uncommon for large denuded areas of bone to retain their vitality.
The onset of infection is indicated by restlessness, throbbing pain and heat in the wound, a feeling of chilliness or the occurrence of a rigor, and tension of the stitches from oedema of the surrounding tissues. The oedema often extends to the eyelids and face; a puffiness of the eyelids, indeed, is not infrequently the first evidence of the occurrence of infection in the wound.
Treatment.--When suppuration ensues, the stitches should be removed, the wound opened up and purified with eusol, and packed. A dressing of ichthyol and glycerine should be employed for a few days.
Erysipelas of the scalp may originate even in wounds so trivial as to be almost invisible, or from suppurative processes in the region of the frontal sinuses or nasal fossae. It tends to be limited by the attachments of deep fasciae, and seldom spreads to the cheek or neck. Symptoms of cerebral complications, in the form of delirium or coma, and of meningitis may supervene. Cellulitis beneath the aponeurosis from mixed infection is a dangerous complication.
DISEASES OF THE SCALP
#Infective Conditions.#--It is not uncommon for localised abscesses to occur in the subcutaneous cellular tissue in delicate children, and such collections are not infrequently associated with pediculi, impetigo, or chronic dermatitis. They develop slowly and painlessly, and are only covered by a thin, bluish pellicle of skin. It is not improbable that they result from a mixed infection by pyogenic and tuberculous organisms. As a rule they heal quickly after incision and drainage, but when they are allowed to burst, tedious superficial ulcers may form. Localised abscesses may also form in connection with disease of the cranial bones. Suppuration following upon injuries has already been referred to.
Boils and carbuncles are not common on the hairy part of the scalp. Lupus rarely originates on the scalp, although it may spread thither from the face. Syphilitic lesions are common and present the same characters as elsewhere. Gummata may develop in the soft parts, but more commonly they take origin in the pericranium or bone. Eczema capitis is of surgical importance only in so far as it often forms the starting-point of infection of lymph glands by pyogenic and other organisms.
#Cystic and Solid Tumours.#--A great variety of swellings is met with in the scalp.
Sebaceous cysts or wens are of frequent occurrence, and have been described in Volume I.
A dermoid cyst is most commonly situated over the position of the anterior fontanelle, in the region of the occipital protuberance, or at the lateral angle of the orbit. As it frequently lies in a gap in the skull, it may be connected by a pedicle with the dura mater, and is liable to be mistaken for a meningocele.
Serous cysts are occasionally found in the occipital region, and are believed to be meningoceles that have become shut off from the interior of the skull before birth.
Adenomas originating in the sebaceous or sweat glands are sometimes multiple, of a purplish colour, and the skin covering them is thin and glistening. They show a tendency to ulcerate and fungate, giving rise to a foetid discharge, and may be mistaken for epithelioma; they are also liable to become the seat of epithelioma. They are treated by excision.
Large, flat papillomas or warts may be single or multiple; they are of slow growth, and as they may also become the starting-point of epithelioma, they should be removed.
The plexiform neuroma forms a loose soft tumour situated in the course of one or more branches of the trigeminal nerve, especially the supra-orbital branch. In its most aggravated form the tumour hangs over the face or neck in large pendulous masses, and is described as a pachydermatocele (V. Mott).
A sarcoma usually has its origin in the bones of the skull, and only implicates the scalp secondarily.
Epithelioma of the scalp may originate in relation to a wart, an ulcerated wen or sebaceous adenoma, or the cicatrix of a burn. It may affect comparatively young persons, may spread over a wide area, or pass deeply and involve the bone. Free and early removal is indicated.
Rodent cancer may originate on the scalp, but usually spreads thither from the face.
In operating for extensive tumours of the scalp the haemorrhage is sometimes formidable. It may be controlled by an elastic tourniquet applied horizontally round the head, or if, on account of the position of the tumour or from other causes, this is not practicable, by ligation or temporary clamping of the external carotid on one or on both sides.
#Air-containing Swellings#--Pneumatocele Capitis.--Cases have been recorded in which, as a result of pathological or traumatic perforations of the mastoid, and less frequently of the frontal cells, air has passed under the pericranium and given rise to a tense rounded tumour, resonant on percussion, and capable of being emptied by firm pressure. Such swellings exhibit neither pulsation nor fluctuation; and as they are painless, and give rise to almost no inconvenience, they do not call for treatment.
Emphysema of the scalp may follow fractures implicating any of the air sinuses of the skull, the air infiltrating the loose cellular tissue between the pericranium and the aponeurosis, and on palpation yielding a characteristic crepitation. It usually disappears in a few days.
#Vascular Tumours.#--Naevi on the scalp present the same features as elsewhere. If placed over one of the fontanelles, a naevus may derive pulsation from the brain, and so simulate a meningocele.
Cirsoid aneurysm is usually met with in the course of the temporal artery, and may involve the greater part of the scalp. Large, distended, tortuous, bluish vessels pulsating synchronously with the heart are seen and felt. They can be emptied by pressure, but fill up again at once on removal of the pressure. The patient complains of dizziness, headache, and a persistent rushing sound in the head. Ulceration of the skin over the dilated vessels, leading to fatal haemorrhage, may take place.
They may be treated by excision, after division and ligation of the larger vessels entering the swelling; or the dilated vessels may be cut across at several points and both ends ligated. Krogius recommends the introduction of a series of subcutaneous ligatures so as to surround the whole periphery of the pulsating tumour, and interrupt the blood flow. Ligation of the main afferent vessels, or of the external or common carotid, has been followed by recurrence, owing to the free anastomatic circulation in the scalp. In some cases electrolysis has yielded good results.
Traumatic aneurysm of the temporal artery was comparatively common in the days when the practice of bleeding from this vessel was in vogue, but it is seldom met with now.
Arterio-venous aneurysm may also occur in the course of the temporal artery, as a result of injury, and is best treated by complete extirpation of the segments of the vessels implicated.
XII. THE CRANIUM AND ITS CONTENTS
Anatomy and physiology--Cerebral localisation--Lumbar puncture. HEAD INJURIES--Concussion--Cerebral irritation--Compression--Contusion and laceration of the brain, and traumatic intra-cranial haemorrhage: Middle meningeal haemorrhage; Haemorrhage from internal carotid and venous sinuses--Intra-cranial haemorrhage of the newly born. Cerebral oedema--Wounds of brain--After-effects of head injuries--Traumatic epilepsy and insanity--Infective complications.
#Anatomy and Physiology.#--The Cranium is irregularly ovoid in shape, and its floor is broken up by various projections to form three separate fossae--anterior, middle, and posterior--in which rest respectively the frontal, the temporal, and the occipital lobes of the brain; the cerebellum, pons, and medulla oblongata also occupy the posterior fossa.
The outer table is the most elastic layer of the calvarium, and it varies greatly in thickness in different skulls and in different parts of the same skull. It is nourished chiefly from the pericranium which is firmly bound down along the lines of the sutures. The inner or vibreous table is thin and fragile, and its smooth internal surface is grooved by the middle meningeal and other arteries of the dura mater, and by the large venous sinuses. The intermediate layer--the diploe--is highly vascular, branches of the meningeal vessels anastomosing freely in its open porous substance with branches derived from the pericranial vessels. Some of its veins open into the external veins, and others into the intra-cranial sinuses, and they communicate with the emissary veins as these pass through the bone, which explains the spread of infective processes from the structures outside the skull to those within. The possibility of withdrawing blood from the interior of the skull by leeching, bleeding, or cupping depends on the existence of the emissary veins.
The Membranes of the Brain.--The dura mater is a fibro-serous membrane, the outer, fibrous layer constituting the endosteum of the skull, the inner, serous layer forming one of the coverings of the brain. Between the fibrous layer and the bone the meningeal vessels ramify; and along certain lines the two layers split to form channels in which run the cranial venous sinuses. Inside the dura, and separated from it by a narrow space--the sub-dural space--lies the arachno-pial membrane, consisting of an outer (arachnoid) layer which envelops the brain but does not pass into the sulci, and a highly vascular inner layer--the pia mater--which closely invests the brain and lines its entire surface.
The space between these layers--the sub-arachnoid space--is traversed by a network of fine fibrous strands, in the meshes of which the cerebro-spinal fluid circulates. Each nerve-trunk as it leaves the skull or spinal canal carries with it a prolongation of each of these membranes and their intervening spaces. The membranes gradually become lost in the fibrous sheaths of the nerves, and the sub-dural and sub-arachnoid spaces become continuous with the lymph spaces of the nerves.
The cerebro-spinal fluid is secreted by the choroid plexuses and fills the cerebral ventricles, the central canal of the cord, the sub-dural and sub-arachnoid spaces, and the sheaths of the intra-cerebral blood vessels. At the base of the brain, particularly in the posterior fossa, the sub-arachnoid space is wider than elsewhere, forming "cisterns" filled with cerebro-spinal fluid which supports the cerebral structures. Through the foramen of Magendie in the roof of the fourth ventricle the sub-arachnoid fluid of the cranial cavity communicates with that of the vertebral canal.
Although it differs in its chemical constitution from true lymph, the cerebro-spinal fluid seems to functionate as lymph, in addition to acting as a lubricating agent, and playing a part in regulating the vascular supply of the brain. In cases of cerebral haemorrhage, abscess, tumour, or depressed fracture, room is made up to a certain point for the extraneous matter by displacement of cerebro-spinal fluid.
Vascular supply.--The free anastomosis between the vessels entering into the formation of the circulus arteriosus (circle of Willis) ensures an abundant supply of blood to the brain. The larger arteries run in the sub-arachnoid space and give off branches which ramify in the pia mater before entering the cerebral substance. Within the brain, each artery being more or less terminal, there is no free anastomosis between adjacent vessels, with the result that if any individual artery is obstructed the vitality of the area supplied by it is seriously impaired. The venous arrangements are also peculiar in that the veins are thin-walled and valveless, and open into the rigid, incompressible sinuses which run between the layers of the dura mater. Most of the blood passes to the internal jugular vein, and any increase in the pressure of this vessel is immediately transmitted back to the cerebral veins. As the blood vessels project into a rigid case filled with incompressible material, and as the total volume of blood in the brain is constant (Munro and Kelly), any alteration in the supply of blood to the cerebral tissue must be due to an increased velocity of flow, and this in turn depends upon changes in the aortic and vena cava pressure. Thus, if the aortic pressure rises, more blood will enter the cerebral vessels and will move along more rapidly; while if the pressure in the vena cava rises there is obstruction to the passage of blood in the arteries and diminished velocity of flow. The ebb and flow of cerebro-spinal fluid in and out of the spinal canal may also help to control the pressure.
#Nerve Elements.#--The nervous system is composed of a multitude of units, called neurones, each neurone consisting of a nucleated cell, with branching protoplasmic processes or dendrites and one axis-cylinder or axon. The nutrition of an axis cylinder depends on its continuity with a living cell. If the cell dies, the axis cylinder degenerates. If the axis cylinder is severed at any point, it degenerates beyond that point, and the nucleus of the nerve-cell disintegrates--chromatolysis.
The axis cylinder of one cell ends in a number of fine filaments which arborise around another nerve-cell, thus bringing it into physiological, if not anatomical, relationship with the first cell. The termination is called a cell-station or synapsis. In this way the various sections of the nervous system are kept in association with one another and with the rest of the body.
Motor Functions and Mechanism.--The nerve centres, which together make up the motor area, and govern the voluntary muscular movements of the body, are situated in the grey matter of the praecentral or ascending frontal gyrus, and of the frontal aspect of the central sulcus (fissure of Rolando). The upper limit of the motor area reaches on to the mesial aspect of the paracentral lobule, and the lower limit stops short of the lateral cerebral fissure (fissure of Sylvius) (Fig. 179).
Each group of muscles has its own regulating centre, the size of the area representing any group depending upon the character and complexity of the movements performed by the muscles, rather than upon the amount of muscular tissue that is governed by the centre--for example, the centre for the mouth, tongue, and vocal cords is larger than that for the muscles of the trunk.
The motor centres have been localised on the surface of the brain with approximate accuracy. For example, above the superior genu of the praecentral gyrus, the centres governing the hip, knee, and toes are grouped; opposite the genu are the centres for the movements of the trunk; between the superior and middle genua lie the centres for the upper extremity; opposite the middle genu, those for the neck, and below it, those for the face, jaws, and tongue, pharynx and larynx.
#The Motor Tracts.#--It is now generally accepted that there are two paths by which motor impulses pass from the brain: one--the rubro-spinal tract--which controls the more elemental movements of the body, such as standing, walking, breathing, etc.; the other--the pyramidal tract--developed later in the evolution of the nervous system, and concerned with the finer and more skilled movements.
The pyramidal tract is the more important clinically. From the pyramidal cells in the cortex of the Rolandic area, the axis cylinders pass through the centrum ovale towards the base of the brain. They converge at the internal capsule, and pass through the anterior two-thirds of its posterior limb (Figs. 180 and 195). The fibres for the eyes, face, and tongue lie farthest forward, and next in order from before backward, those for the arm and the leg.
From the internal capsule, the motor fibres pass as the pyramidal tract through the crusta of each crus cerebri, the pons and the medulla oblongata. Throughout this part of its course, numerous axons leave the tract, and enter the mid-brain, pons, and medulla in which lie the nuclei of the motor cranial nerves.
At the decussation of the pyramids in the lower third of the medulla, the main mass of the motor fibres crosses the middle line, and enters the lateral column of the spinal cord as the crossed pyramidal tract. The remaining fibres pass down as the direct pyramidal tract, and decussate in the cord near their termination.
The fibres forming the second path pass through the red nucleus in the cerebral peduncle (crus cerebri) and thence by way of the rubro-spinal tract in the lateral column of the cord.
The existence of this double motor path explains how after a hemiplegic stroke in which the pyramidal tract is destroyed while the rubro-spinal tract escapes, the patient is able to perform such primitive movements as are involved in walking or standing, while he is unable to carry out finer movements that require higher education.
The pyramidal and rubro-spinal tracts, in addition to conveying motor impulses, convey impulses that influence muscle tonus and the deep reflexes. The pyramidal tract conveys impulses that inhibit muscle tonus, while the rubro-spinal tract is the path by which excitatory impulses travel. When the inhibitory influences are cut off, as in a lesion of the internal capsule, the paralysed muscles become spastic, and the deep reflexes are exaggerated. When the excitatory impulses are also lost, as in a total transverse lesion of the cord, the paralysed muscles are flaccid and the deep reflexes disappear. In destructive lesions of the lower neurones, the muscles are always flaccid.
The axons passing from the cerebral cortex terminate at different levels in the cord by breaking up into dendrites which arborise around the cells on the grey matter of the posterior horns--this system of cells, axons, and dendritic processes forming an upper neurone. From this synapsis the lower neurone proceeds, its axons travelling to the anterior horn and arborising around the motor cells. The axis cylinders pass out in the anterior nerve roots to the spinal nerves and are continued in them to their distribution in voluntary muscles.
If the continuity of any group of these lower neurones is interrupted, not only do the nerve fibres degenerate, but the nutrition of the muscles supplied by them is interfered with and they rapidly degenerate and waste, and after an interval show the reaction of degeneration. In addition, the reflex arc is disturbed, and reflexes are lost. As these changes do not occur in lesions of the upper neurones, an appreciation of the differences enables us to distinguish between lesions implicating the upper and the lower neurones.
#Sensory Functions and Mechanism.#--Three kinds of sensory impulses pass from the periphery to the brain; (1) deep, or muscular sensibility, (2) protopathic sensibility, and (3) epicritic sensibility.
Deep sensibility includes the recognition of (a) deep pressure, say by the blunt end of a pencil; (b) the position of a joint on passive movement (joint sense); (c) active muscular contraction (kinesthetic sense). The fibres that convey these impulses to the spinal cord pass in the afferent nerves from the muscles, tendons, and bones, and so long as these nerves are intact these sensations are retained, even if the surface of the skin is quite anaesthetic.
Protopathic sensibility is of a lower order than epicritic. It consists in the recognition of painful cutaneous stimuli and of extreme degrees of heat and cold. The fibres concerned are non-medullated and regenerate comparatively quickly after injury, so that protopathic sensibility is regained before epicritic.
Epicritic sensibility is the most highly specialised and permits of the recognition of light touch, e.g., with a wisp of cotton wool, of fine differences of temperature, and of discriminating as separate the points of a pair of compasses 2 cm. apart. These sensations are carried by medullated nerve fibres, and are slow to return after injury to the nerves.
The sensory nerve fibres conveying these different impulses pass to the ganglionic cells of the posterior nerve roots. From each of these cells a process passes into the cord and bifurcates into an ascending and a descending branch. In the cord the fibres rearrange themselves and pass to the brain by a double path. Those that convey sensations of pain and of temperature pass by the spino-thalamic route by way of the tract of Gowers and the fillet to the optic thalamus; those that are concerned with the muscular sense, the joint sense, and tactile discrimination pass up the posterior columns in the tracts of Goll and Burdach to the nuclei gracilis and cuneatus in the medulla, whence they pass to the optic thalamus.
From the cell station in the optic thalamus the fibres proceed to the cortical sensory centres, that for tactile sensation being situated in the post-central (ascending parietal) gyrus; that for muscular and stereognostic sense lying probably in the adjacent portions of the parietal lobe.
In a unilateral lesion of the cord, pain and the temperature sense may be disturbed in one limb, and motor power and tactile sensibility in the other, as the fibres that convey impressions of pain, and those that subserve the discrimination of temperature, pass up and decussate in the cord a few segments above their point of entrance.
#Effects of Lesions of the Motor and Sensory Mechanisms.#--Lesions of the motor mechanism differ in their fundamental characters according as they affect the upper or the lower neurones. The signs also vary according as the affected area is destroyed or merely irritated, say by the pressure of a tumour. Irritative lesions in general produce muscular spasms or convulsions, while destructive lesions cause paralysis. The essential differences in the effects of destructive lesions of upper and lower neurones may be indicated thus:--
Upper Neurone Lesion. Lower Neurone Lesion.
Spastic paralysis of voluntary Flaccid paralysis of voluntary muscles. muscles. No marked wasting of paralysed Marked wasting of paralysed muscles. muscles. No reaction of degeneration. Reaction of degeneration. Exaggeration of reflexes. Loss of reflexes.
Irritative lesions of the sensory mechanism cause numbness and tingling (paraesthesia); more extensive paralytic lesions produce anaesthesia, astereognosis, loss of muscle sense, loss of pain, or inability to distinguish temperature, according to the tracts that are affected.
Lesions of the Upper Motor Neurone may occur in any part of its course. Localised lesions of the motor cortex of an irritative kind, for example, a patch of meningitis, a tumour, meningeal haemorrhage, or a spicule of bone, produce spasms in those groups of muscles on the opposite side of the body that are supplied by the centres implicated--Jacksonian epilepsy. The cortical discharge may overflow into neighbouring centres and cause more widespread convulsive movements, or, if strong and long-continued, may even lead to general convulsions. Consciousness is usually lost before the whole of one side becomes implicated in the spasms; always before they spread to the opposite side. Contracture may occur in the muscles affected after the spasms cease.
If an area of the cortex is destroyed by the lesion, paralysis is produced of the corresponding muscles on the opposite side of the body. At first the paralysed muscles are flaccid, but spasticity soon develops. In some cortical lesions, for reasons not yet understood, the paralysis remains of the flaccid type. The seat and extent of the paralysis depend upon the area of the cortex destroyed. In rare cases the whole motor area is destroyed--cortical hemiplegia; more generally the lesion affects one or more groups of muscles, and occasionally all the muscles of one limb are paralysed--cortical monoplegia. Lesions are often both irritative and destructive, and lead to paralysis of one or more groups of muscles associated with spasms and convulsions of the muscles governed by neighbouring areas of the cortex. Irritation or destruction of the sensory centres may also exist, giving rise to areas of paraesthesia and anaesthesia.
Lesions in the centrum ovale, which destroy the fibres proceeding from the overlying cortex, produce a corresponding spastic paralysis on the opposite side of the body. No irritative phenomena are associated with such a sub-cortical lesion.
Lesions in the region of the internal capsule often produce complete spastic hemiplegia of the opposite side of the body. When the posterior part of the capsule is involved, there are, in addition, hemianaesthesia and hemianopia, and sometimes disturbances of hearing, smell, and taste.
A lesion of the crus may in like manner produce spastic hemiplegia and hemianaesthesia of the opposite side, often associated with a lower neurone paralysis of the third and fourth nerves of the same side (crossed paralysis). The optic tract, which crosses the crus, may also be affected, and hemianopia result.
Lesions of the corpora quadrigemina cause interference with the reaction of the pupil, disturbance of the functions of the oculo-motor nerve and of mastication, ataxia, and inco-ordination of the movements of the limbs.
The symptoms produced by lesions of the pons and medulla vary according to the position of the lesion. If it is unilateral, there may be spastic hemiplegia and hemianaesthesia of the opposite side; if it is situated in the lower part of the pons or in the medulla, there is often also a lower neurone paralysis of one or more of the cranial nerves on the same side as the lesion (crossed paralysis). Paralysis of the external rectus of one eye and of the internal rectus of the other (conjugate paralysis) is frequently found in pontine, and in cortical and internal capsule lesions.
Cerebellar lesions are associated with special symptoms. In ataxia, there is inco-ordination of muscular movements, especially of the coarse movements, such as walking. The gait becomes irregular and staggering, with a tendency to fall, sometimes to the side on which the lesion is situated, sometimes to the opposite side. In patients who cannot walk, ataxia may be tested by ordering repeated pronation and supination of the forearm. Paresis or asthenia may be found in the trunk muscles, or evidenced by weakness of the grip, or drooping of the head to one side. Changes in muscle tone may arise and lead to exaggerated or decreased reflexes, often varying from day to day. Vertigo and nystagmus may also be present, in addition to occipital headache and tenderness on percussion. When one lateral lobe is implicated, the symptoms are referred to the same side; when the median lobe is involved, they are bilateral, and there may be retraction of the neck with extension of the legs, probably as the result of the associated internal hydrocephalus.
A unilateral lesion of the spinal cord causes a lower neurone paralysis of the muscles supplied from the cord at the level of the lesion, with spastic paralysis of the muscles of the same side of the body supplied from a lower level of the cord. The sensory symptoms are variable. Typically there is some anaesthesia in the structures supplied from the damaged section of the cord--incomplete owing to the overlapping by other sensory nerves. Just above the lesion there is irritation of spinal nerves, and hyperaesthesia and pain referred to their distribution. On the same side below the lesion, there is a loss of epicritic, stereognostic and deep sensibility, and on the opposite side below the lesion, loss of the sense of pain and the discrimination between heat and cold. Ordinary tactile sensibility, which is governed by a double path, may or may not be lost on either side below the lesion.
#Other Special Centres.#--The cortical centres for vision lie on the median surfaces of the occipital lobes in the neighbourhood of the calcarine fissure. Each half-vision centre--for there is one in each occipital lobe--receives the fibres from the same side of both retinae. Destruction of one half-vision centre produces the condition known as homonymous hemianopia, in which the medial (nasal) half of one visual field and the lateral (temporal) half of the other is affected, so that there is an inability to see objects situated on the side opposite to the lesion.
Auditory impulses are received in the posterior part of the superior temporal convolution.
Aphasia.--The use of language, spoken or written, as a means of expression depends upon the co-ordination of four different centres: the visual, the auditory, the graphic, and the articulatory. These are situated in different parts of the brain and are connected by sub-cortical association tracts, the main pathway of which lies in the vicinity of the upper end of the fissure of Sylvius. Marie has proved that aphasia results from lesions in this area.
The olfactory and gustatory centres are situated in the uncus close to the pituitary fossa.
Lesions of the frontal cortex anterior to the motor centres, even if extensive, may produce few or no symptoms, and in consequence this region has been called a "silent" area. Occasionally there results a change in temperament or intelligence, and the region is on this account supposed to be concerned with the higher psychical functions. There is evidence that the pre-frontal cortex has a centre for the conscious initiation of movements, and that lesions produce "apraxia," i.e., inability to perform, or clumsiness in voluntarily performing fine movements such as touching the nose with the finger, though such movements may be perfectly carried out unintentionally. This centre is probably situated in the superior and middle left frontal convolutions in right-handed people. The fibres from the centre to the right motor area cross in the anterior part of the corpus callosum.
#Cerebral Localisation.#--The various parts of the brain can be localised in relation to the surface by various methods. That devised by Professor Chiene has been found reliable.
#Relation of Cerebral Centres to the Surface.#--Numerous attempts have been made to formulate rules for locating the different parts of the brain in relation to the surface of the head. The method devised by Chiene is free from many of the difficulties and fallacies common to most other methods, inasmuch as the results obtained do not depend upon making definite measurements in inches, or determining particular angles. Certain fixed and easily recognised bony landmarks--the glabella, the external occipital protuberance, the lateral angular process, and the root of the zygoma--are taken, and connected by lines, which are further subdivided--always being bisected. Figs. 179 and 181 explain the method. The head being shaved, a line (GO) is drawn along the vertex from the glabella (G) to the external occipital protuberance (O). This line is bisected in M, which constitutes the "mid-point." The posterior half of the line MO is bisected in T, constituting the "three-quarters point," and the posterior half TO is bisected in S--"the seven-eighths point." The lateral angular process (E) is next connected to the root of the zygoma (P) by a line EP, and the root of the zygoma with the seven-eighths point by PS; the line EPS thus forms the base line. The lateral angular process is now joined to the three-quarters point by ET. The two segments of the base line EP and PS are bisected in N and R respectively, and these points connected with the mid-point (M) by lines NM and RM. These lines cut off a part of ET--AB, which is now bisected in C, and from C the line CD is drawn parallel to AM.
In this way practically all the points of the brain which are wanted for operative purposes may be mapped out. Thus the quadrilateral space MDCA contains the Rolandic area. MA represents the praecentral sulcus, and if it be trisected in K and L, these points will correspond to the origins of the superior and inferior frontal sulci. The pentagon ABRPN corresponds to the temporal lobe. The apex of the temporal lobe extends a little in front of N. The supra-marginal convolution lies in the triangle HBC. The angular gyrus is at B. A is over the anterior branch of the middle meningeal artery, and the bifurcation of the lateral or Sylvian fissure; AC follows the horizontal limb of the lateral fissure. The transverse or lateral sinus at its highest point touches the line PS at R (Fig. 181).
The fissure of Rolando or central sulcus may be marked out by taking a point half an inch behind the mid-point (M) (Fig. 181), and drawing a line downwards and forwards for a distance of about three and a half inches, at an angle of 67.5 deg. with the line GO. The angle of 67.5 deg. can be readily determined by folding a square piece of paper on itself so as to make a triangle. The angle at the fold equals 45 deg.. By folding the paper again upon itself in the same direction, the right angle of the paper is divided into four angles of 22.5 deg. each. Three of these angles taken together make up the 67.5 deg.. If the straight edge of the paper be placed along the sagittal suture with the angle of folding over the upper end of the fissure of Rolando, the folded edge falls over the line of the fissure (Chiene).
LUMBAR PUNCTURE
Quincke, in 1891, first suggested the withdrawal of cerebro-spinal fluid from the theca in the lumbar region, as a means of relieving excessive intra-cranial tension in tuberculous meningitis, and to obtain specimens of the fluid for diagnostic purposes. The scope of the procedure, both as a therapeutic and as a diagnostic measure, has since been widely extended.
Technique.--The puncture may be made with the patient either lying on his left side, the spine being fully flexed by approximating the knees and shoulders; or sitting on the table with the knees drawn up and the body bent forward. The upper edge of the fourth lumbar spine is identified by drawing a horizontal line across the back at the level of the highest part of the iliac crests (Fig. 183). The space between the fourth and fifth lumbar vertebrae being the widest, is that usually selected. The skin having been purified, an exploring needle, about three inches long, is introduced about half an inch below the fourth lumbar spine in the middle line, and passed for about two inches in a direction forwards and slightly upwards. The needle usually encounters some resistance as it pierces the interspinous ligament, and then enters the sub-arachnoid space. If bone is struck, the needle should be withdrawn and introduced at a different level. If the cerebro-spinal fluid does not escape at once, a stylet should be passed through the needle to clear it of blood-clot or shreds of tissue. When the intra-thecal tension is normal, the fluid trickles away drop by drop, but if it is increased, as, for example, in meningitis, intra-cranial tumour, hydrocephalus, or uraemia, it may escape in a jet.
The normal cerebro-spinal fluid is clear and colourless, has a specific gravity of 1004-1008, and contains a trace of serum globulin and albumose, some chlorides, and a substance which reduces Fehling's solution. Microscopically, it may contain some large endothelial cells and a few lymphocytes, or may be entirely devoid of cells. It does not contain the antitoxins and opsonins which are normally found in the plasma and lymph, hence the liability to infective meningitis after injuries and operations on the central nervous system. With a view to diminishing these risks, hexamine, which is excreted into the cerebro-spinal fluid, is administered for its antiseptic properties in cases of head injury and before intra-cranial operations.
Diagnostic Puncture.--Examination of the fluid withdrawn has proved useful in diagnosis in cases of intra-cranial and intra-spinal haemorrhage, in various forms of meningitis, in cerebral abscess, and in some cases of cerebral tumour.
The first few drops should be discarded, as they may be stained with blood from the puncture, and about 5 c.c. collected in each of two sterile tubes. To determine whether blood in the fluid is due to the puncture or to a pre-existing intra-cranial or intra-thecal haemorrhage, the fluid should be centrifugalised; in the former case the supernatant fluid is clear and limpid, in the latter it retains a yellow tinge. In extra-dural haemorrhage there is no blood in the cerebro-spinal fluid.
In acute meningitis the fluid is turbid, and contains an excess of albumin. Organisms also are present, such as the diplococcus intracellularis in acute cerebro-spinal meningitis; staphylococci, streptococci, and pneumococci, particularly in the intra-cranial complications of middle ear disease. In all cases of acute microbic infection, and especially in the suppurative forms, polynuclear leucocytes are found in the fluid; while in chronic affections, such as tubercle and syphilis, there is an excess of lymphocytes (Purves Stewart). The detection of the tubercle bacillus is confirmatory of a diagnosis of tuberculous meningitis, but, as it is often difficult to find, its absence does not negative this diagnosis. In tuberculous meningitis the clot which forms floats in the centre of the fluid, and is translucent, grey, and flaky; in the pyogenic forms it is yellow, and sticks to the side of the vessel.
In a few cases of malignant tumour of the spinal cord and its membranes, characteristic cells have been found in the fluid after centrifugalising.
In uraemia there is a diminution of chlorides, and an increase of phosphates and sulphates.
The Wasserman test is sometimes positive in the cerebro-spinal fluid, when it is negative in the blood.
Therapeutic Puncture.--In certain cases of cerebral tumour, and of tuberculous meningitis associated with an excessive quantity of fluid in the arachno-pial space, temporary relief of such symptoms of increased intra-cranial tension as headache, vertigo, blindness, or coma, has followed the withdrawal of from 30 to 40 c.cm. of the fluid. Terrier and others have found this measure useful in relieving pain in the head, delirium, and even coma, in cases of basal fracture. Carriere has found it beneficial in some cases of uraemia. The quantity withdrawn must not exceed 40 c.cm., lest the ventricles be emptied and pressure be exerted directly on the basal ganglia (Tuffier). In a number of cases sudden death has followed the withdrawal of cerebro-spinal fluid.
This route is sometimes selected for the induction of spinal anaesthesia, and for the injection of antitoxin in cases of tetanus.
HEAD INJURIES
The brain is protected from injury by moderate degrees of violence applied to the head, by the dense and mobile scalp, the dome-like shape of the skull, the elasticity of its outer table and the buffer-like sutural membrane between the numerous bones of which it is composed, and the various internal osseous projections with the membranes attached to them, all of which tend to diminish vibrations and to disperse forces so that they expend themselves before they reach the brain. Further protection is provided by the water-bed of cerebro-spinal fluid, and by the external buttresses formed by the zygomatic arch and the thick muscular pads related to it, as well as by the mobility of the skull upon the spine.
In all cases of head injury, the questions that dominate the whole clinical outlook are, whether the brain is directly damaged or not, and whether it is likely to become the seat of infection.
It is impossible to consider separately in their clinical aspects injuries of the cranium and injuries of the brain. It seldom happens that one is seriously damaged without the other suffering to a greater or less extent. Sometimes the skull suffers comparatively little, while the brain is severely damaged, but it is rare for a serious injury to the bone to be unaccompanied by definite brain lesions. In any case it is the damage to the brain, however slight, that gives to the injury its clinical importance. It is an old and a true saying that "no injury of the head is so trivial as to be despised or so serious as to be despaired of." Injuries at first sight apparently slight may prove fatal from haemorrhage or infection; on the other hand, recovery has followed injuries of great severity--for example, the famous "American crowbar case," in which a bar of iron three and a half feet long and one and a half inches thick passed through the head, and yet the patient recovered.
It is convenient to consider the injuries of the brain before those of the skull.
TRAUMATIC LESIONS OF THE BRAIN
It is probable that in all cases of injury to the head in which a patient loses consciousness, there is some definite damage to the cerebral tissue. This takes the form of a greater or less degree of contusion or laceration, and the lesions are usually most severe and dangerous when the skull is fractured and fragments are driven in upon the brain, but they may exist--indeed they may be very extensive--in the absence of fracture.
Several degrees are recognised.
(1) Numerous minute petechial haemorrhages may be found widely scattered throughout the brain substance, as a result of a diffused blow on the head, which has shaken up the brain and caused symptoms of cerebral shock or "concussion." We have found, on microscopic examination in such cases, in addition to these small extravasations, collections of colloid bodies, patches of miliary sclerosis, and chromatolysis and vacuolation of nerve-cells.[3]
[3] Miles, Laboratory Reports, Royal College of Physicians, Edinburgh, vol. iv.
(2) In more severe cases there are often several visible areas of extravasation, most commonly in the grey matter of the cortex (Fig. 184). These foci vary in size from a split-pea to a hazel-nut, and consist of a dark central zone of extravasated blood, surrounded by an area of "red softening" of the brain matter, beyond which are numerous minute capillary haemorrhages. These intra-cerebral lesions may be accompanied by an effusion of blood into the meshes of the arachno-pial membrane, and they may occur either at the part of the head struck, or at the opposite pole of the axis of percussion--the so-called point of contre-coup. The symptoms vary with the size and site of the extravasations. It is probable that the phenomena of "cerebral irritation" are to be explained by the occurrence of such haemorrhages widely scattered through the cerebral cortex. Effusions into the cortical motor areas give rise to irritation or paralysis of the muscles governed by the affected centres. Different forms of aphasia and interference with vision or with hearing follow implication of the centres governing these functions. In the pre-frontal and in the lower temporal convolutions no special symptoms seem to follow. When the haemorrhages are extensive and numerous, symptoms of compression may ensue, and these are aggravated when oedema of the brain is superadded.
Localised haemorrhages also occur, although less frequently, in the crura cerebri, the pons, the floor of the fourth ventricle, and the cerebellum. In these situations they usually prove fatal by causing rapidly advancing coma and interference with the respiratory and cardiac centres. The temperature immediately rises to 106 deg. or even 108 deg. F., and a modified form of Cheyne-Stokes respiration is present.
(3) Still more gross lesions, in the form of distinct lacerations, are comparatively common at the tips of the frontal, temporal, and occipital lobes, on the surface of the cerebellum, and at the base of the brain. These are usually associated with symptoms of compression in its most typical form, and as a rule prove fatal. The grey matter is torn, and extensive effusion of blood takes place into the brain substance, and on the surface, filling up the sulci, and distending the arachno-pial space (Fig. 184). In a compound fracture, brain matter may be extruded through the opening in the skull.
(4) The extravasated blood may burst into the lateral ventricles, in which case the pulse becomes small and rapid--130, 160, or even 170. The respiration also is rapid--45 to 60--and greatly embarrassed, and the temperature suddenly rises to 103 deg. or 104 deg. F., and continues to rise till death ensues.
(5) Traumatic Oedema.--It is not uncommon for a diffuse oedematous infiltration of the brain substance or of the arachno-pial membrane to take place in the vicinity of the injured portion of brain. This serous exude, on account of the natural adhesions of the arachno-pia, usually remains limited to the damaged area, but it may become generalised.
Mechanism.--The explanation of these widespread haemorrhages is to be found, according to Duret, in the disturbance of the cerebro-spinal fluid which accompanies a severe blow on the head. This fluid not only surrounds the brain, but it also fills the ventricles, and permeates its substance in every direction in the peri-vascular and perilymphatic spaces. As the brain tissue is incompressible, if an area of the skull is momentarily depressed by a localised blow, space is provided for it by displacement of a quantity of cerebro-spinal fluid, which sets up a fluid wave, and this by hydrostatic pressure increases the tension of the fluid throughout the entire brain. Vessels may be lacerated at any point, either by the flow of this wave or during the ebb which follows the recoil. Hence it is that the lesion is not always at the seat of impact, but may be at the opposite side of the skull or at other remote points.
Repair.--As the disintegrated brain matter is replaced by cicatricial tissue, neither the nerve cells nor the fibres being regenerated, the loss of function of the parts destroyed is usually permanent. A localised extravasation of blood may become encapsulated, and constitute a "haemorrhagic cyst." We have experimentally confirmed Duret's observations and agree with his conclusions.
CLINICAL MANIFESTATIONS OF INJURIES TO THE BRAIN
For convenience, the clinical manifestations of cerebral injury are usually described under the terms "concussion," "cerebral irritation," and "compression," but no precise pathological significance attaches to these terms, they are essentially clinical. As the conditions so described do not occur as independent entities and may overlap or merge into one another their differentiation is more or less arbitrary, and cases are frequently met with that do not run the course characteristic of any of these groups.
#Concussion of the Brain or Cerebral Shock.#--The symptoms associated with concussion of the brain are to all intents and purposes those of surgical shock (Volume I., p. 250), the activity of the vital centres being disturbed by violence acting directly upon the brain tissue instead of by impulses transmitted to it by way of the afferent nerves. Various theories have been put forward to account for the depression of the vital functions in concussion. According to Duret, with whose views we agree, the wave of cerebro-spinal fluid set in motion by the impact of the blow on the skull, passes, both in the ventricles and in the sub-arachnoid space, towards the base, where it impinges upon the pons and medulla, stimulating the restiform bodies and so inducing a fall in the blood pressure and a profound anaemia of the brain. The disturbance of the cerebro-spinal fluid may at the same time produce the microscopic lesions in the brain tissues described on p. 341.
The symptoms of shock may be the only evidence of injury, or they may be superadded to those of fracture of the skull, or laceration of the brain.
The clinical features vary according to the severity of the violence. In the slightest cases the patient does not lose consciousness, but merely feels giddy, faint, and dazed for a few seconds. His mind is confused, but he rapidly recovers, and, perhaps after vomiting, feels quite well again, save for a slight shakiness in his limbs.
In more severe cases, immediately on receiving the blow the patient falls to the ground unconscious. Sometimes he suffers from a general tetanic seizure associated with arrest of respiration, which is usually of short duration and is frequently overlooked, but may prove fatal. The pulse is slow, small, and feeble, and is sometimes irregular in force and frequency. The respirations are short, shallow, slow, and frequently sighing in character. The temperature falls to 97 deg. F., or even lower. The skin is cold and pallid and covered with clammy sweat, and the features are pinched and pale.
In uncomplicated cases the pupils are usually equal, moderately dilated, and react sluggishly to light. The patient can be partially roused by shouting or by other forms of external stimulation, but he soon subsides again into a lethargic condition. Although voluntary movement and the deep reflexes are abolished, there is no true muscular paralysis.
After a period, varying from a few minutes to several hours, he rallies, the first evidence often being vomiting, which is usually repeated. Sometimes reaction is ushered in by a mild epileptiform seizure. He then turns on his side, the face becomes flushed, and gradually the symptoms pass off and consciousness returns. The temperature rises to 99 deg. or 100 deg. F., and in some cases remains elevated for a few days. In most cases it falls again to 97 deg. or 97.5 deg., and remains persistently subnormal for one or two weeks. During reaction the pulse becomes quick and bounding, but after a few hours it again becomes slow, and usually remains abnormally slow (40 to 60) for ten or fourteen days. There is sometimes a tendency to constipation, and for the bladder to become distended, although he has no difficulty in passing water. Very commonly the patient complains of pain in the head for some days after the return of consciousness. Children often sleep a great deal during the first few days, but sometimes they are very fretful.
In cases complicated by gross brain lesions the symptoms of concussion may imperceptibly merge into those of compression or there may be a "lucid interval" of some hours duration.
After-Effects of Concussion.--The majority of patients recover completely. A number complain for a time of headache, languor, muscular weakness, and incapacity for sustained effort--traumatic neurasthenia. Sometimes there is a condition of mental instability, the patient is easily excited, and is unduly affected by alcohol or other stimulants. Occasionally there is permanent mental impairment. It is not uncommon to find that the patient has entirely forgotten the circumstances of the injury and of the events which immediately preceded it. In some instances the memory is permanently impaired. On the other hand, it has occurred that a patient, after concussion, has recovered his memory of a foreign language long since forgotten.
As it is never possible to determine the precise extent of the damage to the brain, the immediate prognosis, even in the mildest cases of concussion, should always be guarded. If the patient has been actually unconscious, the condition should be looked upon as a serious one, and treated accordingly.
Treatment.--The immediate treatment is the same as that of shock. Absolute rest and quietness are called for. When the symptoms begin to pass off, the head should be raised on pillows to prevent congestion and to diminish the risk of bleeding from damaged blood vessels in the brain. The value of applying an ice-bag or Leiter's tubes with a view to arresting haemorrhage inside the skull, is more than doubtful. Lumbar puncture, venesection, or the application of leeches over the temple or behind the ear may be employed with benefit. The use of small doses of atropin and ergotin was recommended by von Bergmann. The bowels should be thoroughly opened by calomel, croton oil, or Henry's solution, and a light milk diet given. The patient is kept in a shaded room, and should be confined to bed for from fourteen to twenty-one days. It is often difficult to convince the patient of the necessity for such prolonged confinement, but the responsibility for curtailing it must rest upon him or his friends. Reading, conversation, and argument must be avoided to ensure absolute rest to the brain.
#Cerebral Irritation.#--In some cases of injury to the head--particularly of the anterior part and the parietal region--as the symptoms of concussion are passing off, the patient begins to exhibit a peculiar train of symptoms, which was graphically described by Erichsen under the name of cerebral irritation. "The attitude of the patient is peculiar, and most characteristic: he lies on one side and is curled up in a state of general flexion. The body is bent forwards and the knees are drawn up on the abdomen, the legs bent, the arms flexed, and the hands drawn in. He does not lie motionless, but is restless, and often, when irritated, tosses himself about. But, however restless he may be, he never stretches himself out nor assumes the supine position, but invariably maintains an attitude of flexion. The eyelids are firmly closed, and he resists violently every effort made to open them; if this be effected, the pupils will be found to be contracted. The surface is pale and cool, or even cold. The pulse is small, feeble, and slow, seldom above 70. The sphincters are not usually affected, and the patient will pass urine when the bladder requires to be emptied; there may, however, though rarely, be retention.
"The mental state is equally peculiar. Irritability of mind is the prevailing characteristic. The patient is unconscious, takes no heed of what passes, unless called to in a loud tone of voice, when he shows signs of irritability of temper or frowns, turns away hastily, mutters indistinctly, and grinds his teeth. It appears as if the temper, as much as or more than the intellect, were affected in this condition. He sleeps without stertor.
"After a period varying from one to three weeks, the pulse improves in tone, the temperature of the body increases, the tendency to flexion subsides, and the patient lies stretched out. Irritability gives place to fatuity; there is less manifestation of temper, but more weakness of mind. Recovery is slow, but though delayed, may at length be perfect...."
The treatment consists in keeping the patient quiet, in a darkened room, on much the same lines as for concussion.
#Compression of the Brain.#--This term is used clinically to denote the train of symptoms which follows a marked increase of the intra-cranial tension produced by such causes as haemorrhage, oedema, the accumulation of inflammatory exudate, or the growth of tumours within the skull. The only pathological idea the term conveys is that there is more inside the skull than it can conveniently hold.
Clinical Features.--The following description refers to compression due to haemorrhage within the skull as a result of injury. In a majority of such cases, the symptoms of compression supervene on those of concussion; in certain conditions, notably haemorrhage from the middle meningeal artery, there is an interval, during which the patient regains complete consciousness, in others the symptoms of concussion gradually and imperceptibly merge into those of compression. The rapidity of onset of the symptoms and their course and duration vary widely according to the nature and extent of the brain lesion. Death may occur in a few hours, or recovery may take place after the patient has been unconscious for several weeks.
The first symptoms are of an irritative character--dull pain in the head, restlessness, and hyper-sensitiveness to external stimuli. The face is suffused, and the pupils at first are usually contracted. The temperature falls to 97 deg., or even to 95 deg. F. Vomiting is not infrequent.
As the pressure increases, paralytic symptoms ensue. The patient gradually loses consciousness, and passes into a condition of coma. The face is cyanosed, and the distension of the veins of the eyelids furnishes an index of the severity of the intra-cranial venous stasis (Cushing). The pulse becomes slow, full, and bounding. The respiration is slow and deep, and eventually stertorous or snoring in character from paralysis of the soft palate, and the lips and cheeks are puffed out from paralysis of the muscles of these parts. The temperature, which at first falls to 97 deg. or even 95 deg. F., in the course of three or four hours usually rises (100.5 deg. or 102.5 deg. F.). If the temperature reaches 104 deg. F., or higher, the condition usually proves fatal. Sometimes it rises as high as 106 deg. or 108 deg. F.--cerebral hyperpyrexia (Fig. 185). Retention of urine from paralysis of the bladder, and involuntary defecation from paralysis of the sphincter ani, are common.
During the progress of the symptoms there is frequently evidence of direct pressure upon definite cortical centres or cranial nerves, giving rise to focal symptoms. Particular groups of muscles on the side opposite to the lesion may first show spasmodic jerkings or spasms (unilateral monospasm), and later the same groups become paralysed (monoplegia). The paralysis frequently affects the whole of one side of the body (hemiplegia) and the oculo-motor nerve is often paralysed at the same time.
The pupils vary so widely in different cases that their condition does not form a reliable diagnostic sign. Perhaps it is most common for the pupil on the same side as the lesion to be contracted at first and later to become fully dilated, while that on the opposite side remains moderately dilated. As a rule, they are irresponsive to light. Ophthalmoscopic examination shows swelling of the disc, and the vessels of the papilla are distended and tortuous.
In cases which go on to a fatal termination, the coma deepens and the muscular and sensory paralyses become general and complete. The vital centres in the medulla oblongata gradually become involved, and death results from paralysis of the respiratory centre. The fatal issue is often hastened by the onset of hypostatic pneumonia. Not infrequently a modified type of Cheyne-Stokes respiration is observed for some time before death ensues.
A similar train of symptoms may ensue in cases of head injury as a result of pyogenic infection having given rise to meningitis or abscess with accumulation of inflammatory exudate.
Pathology.--When any addition is made to the bulk of matter inside the cranial cavity, room is gained in the first instance by the displacement into the vertebral canal of a certain amount of cerebro-spinal fluid. The capacity of the spinal sheath, however, is limited, and as soon as the tension oversteps a certain point, the pressure comes to bear injuriously on the cerebral capillaries, disturbing the circulation, and so interfering with the nutrition of the brain tissue. As the intra-cranial tension still further increases, the pressure gradually comes to affect the cerebral tissue itself, and so the extreme symptoms of compression are produced. The vagus and vaso-motor centres are irritated, and this causes slowing of the pulse, contraction of the small arteries, and increase of the arterial tension which tends to maintain an adequate circulation in the vital centres in the medulla. The Cheyne-Stokes respiration is due to rhythmical variations in the arterial tension: during the period of fall the centres become anaemic and the respiration fails; during the rise the medulla is again supplied with blood, and breathing is resumed (Eyster).
The parts of the brain directly pressed upon become anaemic, while the other parts become congested, and the nutrition of the whole brain is thus seriously interfered with. Different parts of the brain and cord show varying powers of resistance to this circulatory disturbance. The cortex is the least resistant part, and next in order follow the corona radiata, the grey matter of the spinal cord, the pons, and, last, the medulla oblongata. Hence it is that the respiratory and cardiac centres hold out longest.
Depressed Bone as a Cause of Compression.--It is more than doubtful whether a depressed portion of bone is of itself capable of inducing symptoms of compression of the brain. When such symptoms accompany depressed fracture, they are to be attributed either to associated haemorrhage, or to interference with the circulation and consequent oedema which the displaced bone produces. Fragments of bone may, however, aggravate the symptoms by irritating the cerebral tissue on which they impinge.
Foreign Bodies.--The role of foreign bodies, such as bullets, in the production of compression symptoms is similar to that of depressed bone. That foreign bodies of themselves are not a cause of compression seems evident from the fact that it is not uncommon for them to become permanently embedded in the brain substance without inducing any symptoms. Not only have bullets, the points of sharp instruments, and other substances remained embedded in the brain for years without doing harm, but in many cases the patients have continued to occupy important and responsible positions in life.
Differential Diagnosis.--It not infrequently happens that a patient is found in an insensible condition under circumstances which give no clue to the cause of his unconsciousness. He is usually removed to the nearest hospital, and the house-surgeon under whose charge he comes must exercise the greatest care and discretion in dealing with him. In attempting to arrive at the cause of the condition, numerous possibilities have to be borne in mind, but it is often impossible to make a definite diagnosis. The chief of these causes are trauma, apoplexy or cerebral embolism, epileptic coma, alcohol and opium poisoning, uraemic and diabetic coma, sunstroke, and exposure to cold. The commonest error is to mistake a case of cerebral compression for one of drunkenness. It is scarcely necessary to say that a man who smells of alcohol is not necessarily intoxicated; the drink may have been given with the object of reviving him. It may be that one or other of the above-named conditions has caused the patient to fall, and in his fall he has incidentally sustained an injury to the head, which, however, is in no way responsible for his unconsciousness. Whenever there is the least doubt, therefore, the patient should be admitted to hospital.
In the first instance, careful search should be made for any sign of injury, especially on the head. The discovery of a severe scalp wound or of a fracture of the skull, in association with the symptoms of concussion or compression, will in most cases raise the presumption that the unconsciousness is due to some traumatic intra-cranial lesion. Examination of the fluid withdrawn by lumbar puncture may furnish useful information (p. 338).
In the absence of evidence of a head injury, the stomach should be washed out and its contents examined to see if any narcotic poison is present. The urine also should be drawn off and examined for albumin and sugar.
In haemorrhage due to the rupture of diseased cerebral arteries (apoplexy), or to embolism, the symptoms are essentially those of compression, and, in the absence of a definite history of injury to the head, it is seldom possible to arrive at an accurate diagnosis as to the cause of the condition. The history that the patient has previously had "an apoplectic shock," and the fact that he is up in years and shows signs of arterial degeneration and of cardiac hypertrophy which would favour such haemorrhage, are presumptive evidence that the lesion is not traumatic.
If a history is forthcoming that the patient is an epileptic, there is a strong presumption that the symptoms are those of epileptic coma.
In alcoholic poisoning the examination of the stomach contents will furnish evidence. The patient is not completely unconscious, nor is he paralysed; the pupils are usually contracted, but react; and the temperature is often markedly subnormal. Improvement soon takes place after the stomach has been emptied.
In opium poisoning the general condition of the patient is much the same as in poisoning by alcohol. The pupils, however, are markedly contracted, and do not react to light. When the poison has been taken in the form of laudanum, this may be recognised by its odour.
In the coma of uraemia or of diabetes there is no true paralysis, nor is there stertor. The urine contains albumin or sugar, and there may be oedema of the feet and legs.
Prognosis.--The prognosis depends so much on the nature and extent of the injury to the brain that it is impossible to formulate any general statements with regard to it. It may be said, however, that the symptoms which indicate a bad prognosis are immediate rise of temperature, particularly if it goes above 104 deg. F., the early onset of muscular rigidity, extreme and persistent contraction of the pupils, with loss of the reflex to light, conjugate deviation of the eyes, and the early appearance of bed-sores.
In the majority of cases compression ends fatally in from two to seven days. On the other hand, recovery may ensue after the stuporous condition has lasted for several weeks.
The treatment of compression is considered with the different lesions which cause it; the principle in all cases being to remove, if possible, the cause of the increased pressure within the skull.
#Traumatic Oedema.#--In practice, cases are frequently met with, particularly in children, that do not conform to the classical description of either concussion, cerebral irritation, or compression. The injury may be followed by a varying degree of concussion which soon passes off but leaves the patient in a listless, drowsy state that may persist for days or even for weeks. The cerebration is disturbed, so that while the patient is not unconscious, he is apathetic and has lost his bearings and fails to recognise where or with whom he is. He complains of headache, there is tenderness on percussion over the skull, the knee jerks are diminished or absent, but there is no motor paralysis. In some cases there are localised jerkings, in others generalised convulsive attacks during which the patient becomes deeply cyanosed. The condition differs from compression due to middle meningeal haemorrhage in that it is less severe and is not steadily progressive.
When the symptoms are localised, the condition is probably due to oedematous infiltration of the injured portion of brain; when generalised, to increased intra-cranial tension from serous effusion into the arachno-pial space.
The treatment consists in diminishing the intra-cranial tension by purgation, leeches, bleeding, or lumbar puncture, or if life is threatened, by opening the skull over the seat of injury, or failing evidence of this, by a decompression operation in the temporal region.
INTRA-CRANIAL HAEMORRHAGE
Apart from the haemorrhage that accompanies laceration of brain tissue, bleeding may occur inside the skull, either from arteries or from veins. The effused blood may collect either between the dura mater and the bone (extra-dural haemorrhage), or inside the dura (intra-dural haemorrhage).
#Middle Meningeal Haemorrhage.#--The commonest cause of extra-dural haemorrhage is laceration of the middle meningeal artery. This artery--a branch of the internal maxillary--after entering the skull through the foramen spinosum, crosses the anterior inferior angle of the parietal bone, and divides into an anterior and a posterior branch which supply the meninges and calvaria (Fig. 186). Either branch may be injured in association with fractures, or from incised, punctured, or gun-shot wounds. The vessel may be ruptured without the skull being fractured, and sometimes it is the artery on the side opposite to the seat of the blow that is torn. The most common situations for rupture are at the anterior inferior angle of the parietal bone, in which case the anterior branch is torn (90 to 95 per cent.); and on the inner aspect of the temporal bone, where the posterior branch is torn (5 to 10 per cent.).
It is probable that the size of the haemorrhage depends on the nature, extent, and severity of the injury to the head. The recoil of the skull after the blow separates the dura from the bone, and if the meningeal artery is lacerated or punctured, blood is effused into the space thus formed (Fig. 187). A localised blow therefore results in a small area of separation and a correspondingly small clot; while a diffuse blow is followed by more extensive lesions. It is believed that, once the dura is partly separated, the force of the blood poured out from the lacerated artery is--on the principle of the hydraulic press--sufficient to continue the separation.
Clinical Features.--The typical characteristics of middle meningeal haemorrhage are met with only when the bleeding takes place between the dura and the bone. Under these conditions the symptoms of concussion are usually most prominent at first, and those of compression only ensue after a varying interval, during which the patient as a rule regains consciousness. In some cases, indeed, he is able to continue his work, or to walk home or to hospital, before any evidence of intra-cranial mischief manifests itself. This "lucid interval" helps to distinguish the symptoms due to middle meningeal haemorrhage from those of laceration of the brain substance, as in the latter the symptoms of concussion merge directly into those of compression. Lumbar puncture may aid in the differential diagnosis between extra-and intra-dural haemorrhage, as blood is present in the fluid withdrawn in the latter, but not in the former.
A few hours after the accident the patient experiences severe pain in the head, and he usually vomits repeatedly. For a time he is restless and noisy, but gradually becomes drowsy, and the stupor increases more or less rapidly until coma supervenes. The pulse usually becomes slow and full. The respiration is rapid (30 to 50), and becomes greatly embarrassed and stertorous. The temperature progressively rises, and before death may reach 106 deg. F., or even higher. Monoplegia, usually beginning in the face or arm on the side opposite to the lesion, gradually comes on, and is followed by hemiplegia, from pressure on the motor areas, underlying the clot. The condition of the pupils is so variable as to have no diagnostic value; but if both are widely dilated and irresponsive to light, the prognosis is grave. Death usually ensues in from twenty-four to forty-eight hours, unless the pressure within the skull is relieved by operation; even after removal of the clot death may ensue if the brain has been lacerated, or if there is haemorrhage at the base.
When the haemorrhage takes place from the anterior branch, the clot tends to spread towards the base, and may press upon the cavernous sinus, causing congestion and protrusion of the eye, with paralysis of the oculo-motor nerve and wide dilatation of the pupil.
In some cases of middle meningeal haemorrhage there is no gross injury to the brain; the area underlying the clot is merely compressed and emptied of blood, and, on being exposed, the brain is found flattened, or even deeply indented by the blood-clot, and it does not pulsate. If the clot is removed, the brain may regain its normal contour and its pulsation return. The mortality is over 50 per cent.
If the fracture is compound, the blood can escape, and therefore the pressure symptoms are less evident or may be entirely absent.
It is a fact of some medico-legal importance that haemorrhage from the middle meningeal may not take place till some days, or even weeks, after an injury, which at the time was only attended with symptoms of concussion. This condition is known as traumatic apoplexy.
Treatment.--Immediate operation is imperatively called for, not only to arrest the haemorrhage and remove the clot, but also to ward off the oedema of the brain, which is often responsible for the fatal issue. When there is no external wound, the point at which the skull is to be opened is determined by the symptoms; for example, paralysis of the arm and face on one side indicates trephining over the centres governing these parts on the side opposite to the paralysis.
If the bleeding cannot otherwise be arrested it may be necessary to ligate the external carotid artery. It has been suggested by J. B. Murphy that, when the patient is seen while the symptoms of compression are coming on, instead of trephining, the haemorrhage from the meningeal vessels should be arrested by applying a ligature to the external carotid, under local anaesthesia.
Injury to the #internal carotid# artery within the skull may result from penetrating wounds, or may be associated with a fracture of the base. It is almost invariably fatal. In some cases a communication is established between the artery and the cavernous sinus, and an arterio-venous aneurysm is thus produced. Ligation of the internal carotid in the neck or of the common carotid is the only feasible treatment.
Injuries of the #venous sinuses# may occur apart from gross lesions of the skull, but as a rule they accompany fractures and penetrating wounds. The transverse (lateral), superior sagittal (longitudinal), and cavernous sinuses are those most frequently damaged. On account of the low pressure in the sinuses, spontaneous arrest of extra-dural haemorrhage usually takes place, and recovery ensues. In some cases, however, the amount of blood extravasated is sufficient to cause compression. If the dura mater is torn, and the blood passes into the sub-arachnoid space, it may spread over the whole surface of the brain. Sometimes the bleeding only commences after a depressed fracture has been elevated.
In the presence of an open wound, the venous source of the bleeding is recognised by the dark colour of the blood and the continuous character of the stream. It may be arrested by pressure with gauze pads or by packing a strand of catgut into the sinus (Lister), or, if this fails, by grasping the sinus with forceps and leaving these in position for twenty-four or forty-eight hours. A small puncture in the outer wall of the sinus may be closed with sutures. Signs of increasing compression call for trephining and opening of the dura if this is necessary to admit of the clot being removed.
#Intra-cranial Haemorrhage in the Newly-Born.#--An extravasation of blood into the arachno-pial space frequently occurs during birth. The observations of Cushing seem to show that this is usually due to tearing of the delicate cerebral veins which pass from the cortex to the superior sagittal sinus, from the strain put upon them by the overlapping of the parietal bones, in the moulding of the head. It may sometimes be due to an excessive degree of asphyxia during birth. The extravasation is usually most marked over the central area of the cortex near the middle line, and it is often bilateral.
This condition is most frequently met with in a first-born child--and more often in boys than in girls--the labour having been prolonged and difficult, and the presentation abnormal. There is usually a history that the infant was deeply cyanosed when born, and that there was difficulty in getting it to breathe. As a rule, there is no external evidence of trauma. The anterior fontanelle is tense and does not pulsate, the pulse is slow, and for several days the child appears to have difficulty in sucking and swallowing, and is abnormally still. In the course of a few days definite symptoms of localised pressure appear. It is noticed that one leg or arm, or one side of the body is not moved, or both sides may be affected; when the paralysis is bilateral, the absence of movement is more liable to be overlooked. The infant may suffer from convulsions; there may be paralysis of certain of the ocular muscles, and inequality of the pupils; sometimes there is blindness. Persistent rigidity of the limbs, with turning of the thumbs towards the palm, is present in some cases. Lumbar puncture may reveal the presence of blood corpuscles in the cerebro-spinal fluid, and increase in the tension of the fluid.
If untreated, the condition is usually followed by the development of spastic paralysis of one or more limbs, on one or on both sides of the body (Little's disease), by blindness, deafness, and varying degrees of mental deficiency, or by Jacksonian epilepsy.
Treatment.--To obviate these after-effects the clot may be removed by raising an osteo-plastic flap, including nearly the whole of the parietal bone. The operation should be undertaken within the first week or two, and great care must be taken to keep up the body-warmth, and to prevent undue loss of blood. It may be necessary to operate on both sides, an interval being allowed to elapse between the two operations.
For the immediate relief of increased intra-cranial tension, the daily withdrawal of 10-12 c.c. of cerebro-spinal fluid by lumbar punctures may be employed, or a sub-temporal decompression operation may be performed.
WOUNDS OF THE BRAIN
#Wounds of the Brain.#--Incised wounds of the brain usually result from sabre-cuts, hatchet blows, or circular saws. A portion of the scalp and cranium may be raised along with a slice of brain matter, and in some cases the whole flap is severed. The extent of the injury, the conditions under which it is received, and the liability to infection, render such wounds extremely dangerous.
Punctured wounds may be inflicted on the vault by stabs with a knife or dagger, or by other sharp objects, such as the spike of a railing. More frequently a pointed instrument, such as a fencing foil, the end of an umbrella, or a knitting needle, is thrust through the orbit into the base of the brain. Occasionally the base of the skull has been perforated through the roof of the pharynx, for example, by the stem of a tobacco-pipe. All such wounds are of necessity compound, and the risk of infection is considerable, particularly if the penetrating object is broken and a portion remains embedded within the skull. The infective complications of such injuries are described later.
Bullet wounds have many features in common with punctured wounds. There is more contusion of the brain substance, disintegrated brain matter is usually found in the wound of entrance, and the bullet often carries in with it pieces of bone, cloth, or wad, thus adding to the risk of infection.
Aseptic foreign bodies, especially bullets, may remain embedded in the brain without producing symptoms.
The treatment of punctured wounds consists in enlarging the wounds in the soft parts, trephining the skull, and removing any foreign body that may be in it, purifying the track, and establishing drainage.
AFTER-EFFECTS OF HEAD INJURIES
Various after-effects may follow injuries of the head. Thus, for example, chronic interstitial changes (sclerosis) may spread from an area of cicatrisation in the brain; or softening may ensue, either in the form of pale areas of necrosis (white softening) or of haemorrhagic patches (red softening). The symptoms vary with the area implicated. Adhesions between the brain and its membranes may produce severe headache and attacks of vertigo, especially on the patient making sudden exertion.
After a head injury, the patient's whole mental attitude is sometimes changed, so that he becomes irritable, unstable, and incapacitated for brain-work--traumatic neurasthenia. In some cases self-control is lost, and alcoholic and drug habits are developed.
#Traumatic epilepsy# may ensue as a result of some circumscribed cortical lesion, such as a spicule of bone projecting into the cortex, the presence of adhesions between the membranes and the brain, a cicatrix in the brain tissue leading to sclerosis or a haemorrhagic cyst in the membranes or cerebral tissue.
The convulsive attacks are of the Jacksonian type, beginning in one particular group of muscles and spreading to neighbouring groups till all the muscles of the body may be affected. The convulsions may begin soon after the injury, for example, when the cause is a fragment of bone irritating the cortex; in other cases it may be several years before they make their appearance. The onset is usually sudden, and the "signal symptom"--for example, jerking of the thumb, conjugate deviation of the eyes, or motor aphasia--indicates the seat of the lesion. At first the attacks only recur at intervals of, it may be weeks or months, but as time goes on they become more and more frequent, until there may be as many as forty or fifty in a day. Sometimes the patient loses consciousness during the fit; sometimes he remains partly conscious. In course of time the same degenerative changes as occur in other forms of epilepsy ensue: certain groups of muscles may become paralysed; the patient may pass into a state of idiocy, or into what is known as the "status epilepticus," in which the fits succeed one another without remission, the breathing becomes stertorous, the temperature rising, the pulse becoming very rapid; finally coma supervenes, and the patient dies.
Treatment.--The administration of bromides is only palliative. Operation is indicated only when the "signal symptom" indicates a limited and accessible portion of the brain as the seat of the lesion, or when there is a depression of the skull or other definite evidence of cranial injury. The more recent the injury the better is the prospect, as secondary changes are less likely to have taken place, and the peculiarly irritable state of the brain--sometimes referred to as the "epileptic habit"--has not developed. The operation consists in opening the skull freely, and removing any discoverable cause of irritation--depressed bone, thickened and adherent membranes, a cyst, or sclerosed patch of cortex; it may be necessary to interpose a layer of tissue, a flap of fascia lata, for example, between the bone and the cortex of the brain. The point at which the skull is opened is determined by the seat of the injury and the focal brain symptoms.
The return of fits within a few days of the operation does not necessarily mean failure, as they often pass off again. Complete and permanent cure is not common, but the number and severity of the attacks are usually so far diminished that life is rendered bearable.
#Traumatic insanity# may follow injury to any part of the brain, and it may come on either immediately or after an interval. It may or may not be associated with epilepsy. Any form of insanity may occur, either as a direct result of the trauma, or from the resistance of the brain being lowered by the injury in a patient predisposed to insanity. When insanity follows as a direct consequence of injury, the organic lesion is usually a superficial one, and the disturbance of brain function is generally due to reflex irritation of the dura mater (Duret). These facts possibly explain the immediate improvement which occasionally follows the opening of the skull at the point of injury and removal of the exciting cause. Cases occurring within a few days of the injury usually recover within a month or two. The later the condition is in developing the less obvious is the relationship between the trauma and the insanity, and therefore the worse is the prognosis.
Meningitis, sinus thrombosis, and cerebral abscess may follow upon any form of head injury attended with infection. The clinical features--save for the history of a trauma--correspond so closely with those of the same conditions occurring apart from injury, that they are most conveniently considered together (p. 374).