XIII. INJURIES OF THE SKULL…

XIII. INJURIES OF THE SKULL

Contusions--FRACTURES--Of the vault: Varieties--Of the Base: Anterior fossa--Middle fossa--Posterior fossa.

The bones of the skull may be contused or fractured. These injuries are not in themselves serious: their clinical importance is derived from the injury to the intra-cranial contents with which they are liable to be associated.

#Contusion# of the skull may result from a fall, a blow, or a gun-shot injury. In the majority of cases the damage to soft parts--scalp, meningeal vessels, or brain--overshadows the osseous lesion, which of itself is comparatively unimportant.

FRACTURES OF THE SKULL

While it is convenient to consider separately fractures of the vault and fractures of the base of the skull, it is to be borne in mind that it is not uncommon for a fracture to involve both the vault and the base. Fractures in either situation may be simple or compound.

FRACTURES OF THE VAULT

#Mechanism.#--When the skull is broken by direct violence, the fracture takes place at the seat of impact, and its extent varies with the nature of the impinging object and the degree of violence exerted. If, for example, a pointed instrument, such as a bayonet, a foil, or a spike, is forcibly driven against the skull, the weapon simply crashes through the bone, disintegrating it at the point of entrance, and cracking or splintering it for a variable, but limited, distance beyond. On the other hand, when the head is struck by a "blunt" object--for example, a batten falling from a height--the force is applied over a wider area and the elastic skull bends before it. If the limits of its elasticity are not exceeded, the bone recoils into its normal position when the force ceases to act; but if the bone is bent beyond the point from which it can recoil, a fracture takes place--"fracture by bending." The bone gives way over a wide area, the affected portion may be comminuted, and one or more of the fragments may remain depressed below the level of the rest of the skull. Cracks and fissures spread widely in different directions--often (70 to 75 per cent.) extending into the base. In almost all fractures of the vault the inner table splinters over a wider area than the outer, partly because it is more brittle and is not supported from within, but also because the diffusion of the force as it passes inwards affects a wider area. If a bullet traverses the cranial cavity the inner table is more widely shattered at the aperture of entrance, and the outer table at the aperture of exit. Von Bergmann reported thirty cases in which the inner table alone was fractured by a blow on the head.

Fractures by indirect violence--that is, fractures in which the bone breaks at a point other than the seat of impact--are almost always due to violence inflicted with a blunt object, and acting over a wide area--such, for example, as when the head strikes the pavement. Much discussion has taken place as to the method of their production. It has been shown that when the skull is depressed at one point by a force impinging on it, it bulges at another, so that its whole contour is altered. But the elasticity of the bone varies at different parts of the skull, owing to differences in thickness and in structure. If, therefore, the part which is depressed--that is, the part directly struck--happens to be less elastic than the part which bulges, it gives way, and a fracture by "bending" results; but if the bulging part is the less elastic, it bursts outwards--fracture by "bursting." The term "fracture by contre-coup" has been incorrectly applied to such fractures when the area of bulging happens to be opposite to the seat of impact. Contre-coup, properly so-called, is only possible in a perfectly spherical body, which, of course, the skull is not.

When a high-velocity bullet penetrates the head, it exerts on the incompressible, semi-fluid brain an explosive (hydro-dynamic) force, which is transmitted to all points on the inner surface of the skull and leads to shattering of the bone.

Repair.--The repair of fractures of the skull is usually attended with an exceedingly small amount of callus. Except in the presence of infection, separated fragments live and become reunited, but they may unite in such a manner as to project towards the brain and, by irritating the cortical centres, cause traumatic epilepsy. In comminuted fractures, the lines of fracture remain permanently visible on the bone, but fissured fractures may leave no trace. Gaps left in the skull by injury or operation are, after a time, filled in by a fibrous membrane, which may undergo ossification from the periphery towards the centre, but unless the aperture is a small one it is seldom completely closed by bone. The new bone which forms is derived from the old bone at the margins of the opening. Permanent defects in the skull are chiefly injurious if they are accompanied by lesions of the underlying dura, such as adhesions to the brain; large gaps may cause giddiness on stooping, or on forcible expiration, as in blowing the nose or playing a wind instrument.

#Varieties.#--For descriptive purposes, fractures of the vault are divided into the fissured, the punctured, the depressed, and the comminuted varieties. Clinically, however, these varieties are often combined. The practical importance of a given fracture depends upon whether it is simple or compound, rather than upon the exact nature of the damage done to the bone. Compound fractures which open the dura mater are the most serious. Simple fractures result, as a rule, from diffuse forms of violence, and are liable to spread far beyond the seat of impact. Compound fractures result from severe and localised violence--for example, the kick of a horse or the blow of a hammer--and tend to be limited more or less to the seat of impact. In gun-shot injuries, however, there are usually numerous fissures radiating from the point at which the missile enters the skull.

#Fissured fractures# generally result from blows by blunt objects or from falls, and they usually extend far beyond the area struck, in most cases passing into the base. The fissure may pass through the bone vertically or obliquely, and it may implicate one or both tables. So long as the fracture is simple, it can scarcely be diagnosed except by inference from the associated symptoms of meningeal or cerebral injury. When compound, the crack in the bone can be seen and felt. It is recognised by the eye as a split in the bone, filled with red blood, which, as often as it is sponged away, oozes again into the gap. In fractures by bursting a tuft of hair may be caught between the edges of the fracture, and this adds to the difficulty of purifying the wound.

Diagnosis.--A normal suture may be mistaken for a fissured fracture. A suture, however, may generally be recognised by its position, the irregularity of its margins, and the absence of blood between its edges. At the same time, it is not uncommon, especially in children, for a suture to be sprung by violence applied to the head, or for a fissured fracture to enter a suture and, after running in it for some distance, to leave it again. The edges of a clean cut in the periosteum may be mistaken for a fissure in the bone, especially if reliance is placed on the probe for diagnosis. This error can be avoided by raising the edge of the periosteum from the bone, with the gloved finger. On combined auscultation and percussion a peculiar "hollow-cask" sound may be detected in some cases of fissured fracture of the vault.

Fissured fractures as such call for no treatment. When compound, the wound must be disinfected; and intra-cranial complications, such as meningeal haemorrhage, laceration of the brain, or infection, are to be treated on the lines already described.

#Punctured fractures# are of necessity compound, and on account of the risks of infection are to be looked upon as serious injuries. They result from the localised impact of a sharp, and usually infected object the point of which is not infrequently left either in the bone or inside the skull. Fragments of bone are often driven into the brain, and short fissures frequently pass in various directions from the central aperture.

Diagnosis.--When the instrument impinges on the head obliquely, after piercing the scalp it may pass for some distance under it before perforating the skull, so that on its withdrawal a valvular wound is left, and at first sight it appears that only the scalp is involved. Sometimes a foreign body left in the gap so fills it up that it is difficult to detect the fracture with a probe or even with the finger. In all doubtful cases the scalp wound should be sufficiently enlarged to exclude such errors. We have known of a case of a man who died of meningitis resulting from a punctured fracture of the vault caused by the spoke of an umbrella, the fracture having escaped recognition until the meningeal symptoms developed.

Treatment.--The scalp wound must be purified, being opened up as far as necessary for this purpose. The infected portion of bone should be removed to render possible the purification of the membranes and brain, and to permit of drainage.

#Depressed and Comminuted Fractures.#--As these varieties almost always occur in combination, they are best considered together. The terms "indentation fracture," "gutter fracture," "pond fracture," have been applied to different forms of depressed fracture, according to the degree of damage to the bone and the disposition of the fragments (Figs. 188, 189, 190). These fractures may be simple or compound.

As a rule the whole thickness of the skull is broken, and, as usual, the inner table suffers most. In infants the bones may be merely indented, the fracture being of the greenstick variety. All degrees of severity are met with, from a simple, localised indentation of the bone, to complete smashing of the skull into fragments.

Diagnosis.--When compound, the nature of these fractures is readily recognised on exploring the wound, but their extent is not always easy to determine, and it is not uncommon for extensive fissures to pass into the base.

A haematoma of the scalp may readily be mistaken for a depressed fracture. The condensation of the tissues round the seat of impact and the soft coagulum in the centre, closely simulate a depression in the bone; but if firm pressure is made with the finger, the irregular edge of the bone can be recognised, and the depressed portion is felt to be on a lower level. On the other hand, a depression in the bone is sometimes obscured by an overlying haematoma, and unless great care is taken the fracture may be overlooked.

Treatment.--All are agreed that compound depressed and comminuted fractures--whether associated with cerebral symptoms or not--should be operated on to enable the wound to be purified, and the normal outline of the skull to be restored by elevating or removing depressed or separated fragments. Except in young children, in whom considerable degrees of depression are frequently righted by nature, most surgeons recommend operative interference even in simple fractures with the object of elevating the depressed bone, and to anticipate subsequent complications such as persistent headache, attacks of giddiness, traumatic epilepsy, or insanity. Others, including von Bergmann and Tilmanns, consider that the risk of such sequelae ensuing is not sufficient to justify a prophylactic operation of such severity as trephining.

The operation is described in Operative Surgery, p. 93.

FRACTURES OF THE BASE

The base of the skull may be fractured by a pointed object, such as a fencing foil, a knitting pin, or the end of an umbrella, being forced through the orbit, the nasal cavities, or the pharynx. These injuries will be referred to in describing fractures of the anterior fossa.

The majority of basal fractures result from such accidents as a fall from a height, the patient landing on the vertex or on the side of the head, or from a heavy object falling on the head. The violence is therefore indirect in so far as the bone breaks at a point other than the seat of impact.

In other cases the base is broken by the patient falling from a height and landing on his feet or buttocks, the force being transmitted through the spine to the occiput, and the bone giving way around the foramen magnum. Sometimes the condyle of the lower jaw is driven through the base of the skull by a blow or fall on the chin, and fissures radiate into the base from the glenoid cavity. It is usual to describe these also as fractures by indirect violence, but as the skull gives way at the point where it is struck, these are really fractures by direct violence. Von Bergmann, Bruns, and Messerer have done much to elucidate the mechanism of basal fractures.

In the consideration of the mode of production of basal fractures by indirect violence, the irregular shape of the cavity, the varying strength and thickness of its different parts, and the existence of the foramina through the bone are to be borne in mind. The force acting on the skull tends to increase one diameter of the cavity, and to diminish the opposite diameter. The resulting fracture, therefore, is due to bursting of the skull, and tends to take place at the part which has least elasticity--that is, at the base. It has been found that the site and direction of basal fractures bear a fairly constant relation to the direction of the force by which they are produced. When, for example, the skull is compressed from side to side, the line of fracture through the base is usually transverse, and it may implicate one or both sides (Fig. 191). On the other hand, when the pressure is antero-posterior, the fracture tends to be longitudinal; and when oblique, it tends to be diagonal.

Fractures of the base usually take the form of a single fissure, or a series of fissures, which, as a rule, run through the foramina in their track. Small portions of bone are sometimes completely separated. It is common for a fissure through the base to be continued for a considerable distance on to the vault.

The fracture may involve only one fossa, but as a rule fissures radiate into two or all of them. Fractures of the anterior and middle fossae are usually rendered compound by tearing of the mucous membrane of the nose, the pharynx, or the ear.

Basal fractures are frequently associated with contusion and laceration of the brain, and also with injuries of one or more of the cranial nerves.

#Fracture of the anterior fossa# may result from a blow on the forehead, nose, or face; or from a punctured wound of the orbit or of the nasal cavity. Often the injury is at first considered trivial, and it is only when infective complications, in the form of meningitis or cerebral abscess, develop, that its true nature is suspected. This fossa may also be implicated in fractures of the vault, fissures extending from the vertex to the orbital plate of the frontal bone, or to the lesser wing of the sphenoid.

Clinical Features.--Unless the fracture is compound through opening into the nose or pharynx, there are few symptoms by which it can be recognised. When compound, there may be bleeding from the pharynx or nose from tearing of the periosteum and mucous membrane related to the basi-sphenoid and ethmoid respectively. When the haemorrhage is profuse, it is probable that the meningeal vessels or even the venous sinuses have been torn. Cerebro-spinal fluid may escape along with the blood, but it is seldom possible to recognise it. If the flow is long continued, the patient may be conscious of a persistent salt taste in the mouth, due to the large proportion of sodium chloride which the fluid contains. In very severe injuries, brain matter may escape through the nose or mouth.

Fracture of the anterior fossa is often accompanied by extravasation of blood into the orbit, pushing forward the eyeball and infiltrating the conjunctiva (sub-conjunctival ecchymosis). This occurs especially when the orbital plate of the frontal bone is implicated. The blood which infiltrates the conjunctiva passes from behind forwards, appearing first at the outer angle of the eye and spreading like a fan towards the cornea. Later it spreads into the upper eyelid. When the orbital ridge is chipped off, without the cavity of the skull being opened into, the haemorrhage shows at once both under the conjunctiva and in the upper lid. If the frontal sinus is opened, air may infiltrate the scalp.

The olfactory, optic, oculo-motor, pathetic, ophthalmic division of the trigeminal, and the abducens nerves are all liable to be implicated.

Diagnosis.--It is scarcely necessary to state that bleeding from the nose or mouth may occur after a blow on the face without the occurrence of a fracture of the skull. It is only when it is long continued and profuse that the bleeding suggests a fracture. Similarly effusion of blood in the region of the orbit may be due to a simple contusion of the soft parts ("black eye"), or to gravitation of blood from the forehead or temple. Sub-conjunctival ecchymosis also may occur independently of a fracture implicating the anterior fossa--for example, in association with an ordinary black eye, or with fracture of the orbital ridge or of the zygomatic (malar) bone.

Finally, paralysis of the cranial nerves may result from pressure of blood-clot, or from the nerves being torn without the skull being fractured.

#Fracture of the middle fossa# is usually the result of severe violence applied to the vault, as, for example, when a man falls from a height, or is thrown from a horse and lands on his head.

Clinical features.--The most conclusive sign of fracture of the middle fossa is the escape of dark-coloured blood in a steady stream from the ear, followed by oozing of cerebro-spinal fluid. The bleeding from the ear may go on for days, the blood gradually becoming lighter in colour from admixture with cerebro-spinal fluid. Finally the blood ceases, but the clear fluid continues to drain away, sometimes for weeks, and in such quantity as to soak the dressings and the pillow. In our experience, the escape of cerebro-spinal fluid is much less common than is generally supposed. In most cases, on examining the ear with a speculum, the tympanic membrane is found to be ruptured; when it is intact, the blood and cerebro-spinal fluid may pass down the Eustachian tube into the pharynx. The escape of brain matter from the ear is exceedingly rare. Emphysema of the scalp sometimes results when the fracture passes through the mastoid cells. The facial and acoustic nerves and the maxillary and mandibular divisions of the trigeminal are frequently implicated. Deafness is a serious and not uncommon accompaniment of fracture of the middle fossa, as the fracture involves the labyrinth and is attended with haemorrhage and the formation of new bone.

Diagnosis.--Care must be taken not to mistake blood which has passed into the ear from a scalp wound, or which has its origin in a fracture of the wall of the external auditory meatus or a laceration of the tympanic membrane, for blood escaping from a fracture of the base. Under these conditions the blood is usually bright red, is not accompanied by cerebro-spinal fluid, and the flow soon stops. It is on record[4] that blood and cerebro-spinal fluid may escape along the sheath of the acoustic nerve without the bone being broken.

[4] Miles, Edinburgh Medical Journal, 1895.

#Fracture of the posterior fossa# is produced by the same forms of violence as cause fracture of the middle fossa; it is specially liable to result if the patient falls on the feet or buttocks.

Clinical Features.--Sometimes a comparatively limited fracture of the occipital bone results, and in the course of a few days blood infiltrates the scalp in the region of the occiput and mastoid, or may pass down in the deeper planes of the neck. As a rule, however, there is no immediate external evidence of fracture. The patient is generally unconscious, and shows signs of injury to the pons and medulla, causing interference with respiration, which soon proves fatal. The rapidly fatal issue of these cases usually prevents the manifestation of any injury to the posterior cranial nerves.

Diagnosis of Basal Fractures.--In the diagnosis of fractures of the base, reliance is to be placed chiefly upon: (1) the nature of the injury; (2) the diffuse character of the cerebral symptoms; (3) the evidence of injury to individual cranial nerves; (4) the occurrence of persistent bleeding from the nose, mouth, or ear; (5) the extravasation of blood under the conjunctiva or behind the mastoid process; and (6) the presence of blood in the cerebro-spinal fluid withdrawn by lumbar puncture. In rare cases the diagnosis is made certain by the escape of cerebro-fluid or of brain matter from the nose, mouth, or ear.

It must be admitted, however, that in a large proportion of cases which end in recovery, the diagnosis of fracture of the base is little more than a conjecture. The external evidence of damage to the bone is so slight and so liable to be misleading, that little reliance can be placed upon it. The associated cerebral and nervous symptoms also are only presumptive evidence of fracture of the bone. In all cases, however, in which there is reason to suspect that the base is fractured, the patient should be treated on this assumption. It is often found that, when there are no cerebral symptoms present, it is difficult to convince the patient of the necessity for undergoing treatment, and of the risk involved in his leaving his bed and resuming work.

Prognosis in Basal Fractures.--The prognosis depends upon the severity of the cerebral lesions, and on the occurrence of traumatic oedema or infective intra-cranial complications. Many cases prove fatal within a few hours from the associated injury to the brain, the patient dying from cerebral compression due to haemorrhage. If the patient survives two days, the prognosis is more hopeful (Wagner). It is possible that the free escape of blood from the nose or ear may in some cases prevent compression, and to a certain extent render the prognosis more favourable. Punctured fractures are frequently fatal from infective complications--meningitis, sinus thrombosis, and cerebral abscess. These complications are also liable to occur in fractures rendered compound by opening into the nose, pharynx, or ear, but they are less common than might be expected.

Treatment.--The general treatment includes that for all head injuries. In a number of cases attended with symptoms of compression, benefit has followed the relief of intra-cranial tension by a decompression operation. The withdrawal of 30 or 40 c.c. of cerebro-spinal fluid by lumbar puncture has also proved beneficial in the same way; Quenu strongly recommends repeated puncture in serious cases. In a few cases this procedure has been followed by sudden death.

Steps must be taken to prevent infection from the mucous surfaces implicated. This is exceedingly difficult in fractures opening into the pharynx and nose. Owing to the general condition of the patient, it is usually impossible to employ nasal douching or mouth washes, but spraying the cavities with peroxide of hydrogen or other antiseptics may be employed with benefit. In fractures of the middle fossa, the ear should be gently sponged out and the meatus plugged with gauze, retained in position by adhesive plaster or a bandage. When there is a persistent escape of blood or cerebro-spinal fluid, the dressing requires to be changed frequently.

In compound fractures of the anterior fossa due to perforation through the orbit, the frontal bone should be trephined to admit of the removal of loose fragments or of any foreign body that may have entered the skull and to provide for drainage.

XIV. DISEASES OF THE BRAIN AND MEMBRANES

Pyogenic diseases--Meningitis: Varieties--Abscess: Varieties--Sinus phlebitis--Intra-cranial tuberculosis. Cephaloceles--Meningocele--Encephalocele-- Hydrencephalocele--Traumatic cephal-hydrocele--Hydrocephalus; Varieties--Micrencephaly. Cerebral tumours. Tumours of the pituitary body. Epilepsy--Hernia cerebri. Surgical affections of cranial nerves--Cervical sympathetic.

PYOGENIC DISEASES

The most important intra-cranial conditions that result from infection with pyogenic bacteria are: meningitis, abscess of the brain, and phlebitis of the venous sinuses.

The organisms most frequently associated with these conditions are the staphylococcus aureus and the streptococcus, but it is not uncommon to meet with mixed infections in which other bacteria are present--particularly the pneumococcus, the bacillus foetidus, the bacillus coli, the bacillus pyocyaneus, and the diplococcus intracellularis.

By far the most common source of intra-cranial infection is chronic suppuration of the middle ear and mastoid antrum, the organisms passing from these cavities to the interior of the skull directly through a perforation of the tegmen tympani or of the wall of the sigmoid groove, or being carried in the blood stream by the emissary veins. In some cases the infection travels along the sheaths of the facial and acoustic nerves.

Less frequently infective conditions of the nasal cavity and its accessory air sinuses, and compound fractures of the skull, particularly punctured fractures, are followed by intra-cranial complications; or infection is conveyed to the inside of the skull, by way of the emissary veins, from wounds of the scalp, or from such conditions as erysipelas of the face and scalp, malignant pustule, carbuncles, or boils.

At the bedside there is often difficulty in discriminating between the various pyogenic intra-cranial complications, because many of the symptoms are common to all the members of this group, and because more than one condition is frequently present. Thus a localised meningitis spreading to the brain may set up a cerebral abscess; a sinus phlebitis may give rise to a purulent lepto-meningitis; or a cerebral abscess bursting into the sub-arachnoid space may produce meningitis.

MENINGITIS

#Pachymeningitis.#--This term is applied when the infection involves the dura mater--a condition which is usually due to the spread of infection from a localised osseous lesion, such as erosion of the tegmen tympani in chronic suppuration of the middle ear, of the wall of the sigmoid groove in mastoid disease, or of the posterior wall of the frontal sinus in suppuration of that cavity. It also occurs in relation to septic lesions of the cranial bones such as a broken-down gumma, after operations on the cranial bones, and in cases of compound fracture attended with a mild degree of infection and with imperfect drainage. In contusion of the skull without an external wound, the infection may take place through the blood stream.

The layer of the dura in contact with the affected portion of bone is inflamed, thickened, and covered with a layer of granulations--external pachymeningitis--and between it and the bone there is an effusion of fluid. Up to this point the process is largely protective in its effects, and gives rise to no symptoms, beyond perhaps some pain in the head.

In the majority of cases, however, suppuration occurs between the dura and the bone--suppurative pachymeningitis--and leads to the formation of an extra-dural abscess (Fig. 192). When this happens in association with disease in the middle ear or frontal sinus, it is attended with severe headache referred to the seat of the abscess, a sudden rise of temperature preceded by shivering, and other evidence of the absorption of toxins. Over the situation of the abscess, the scalp becomes swollen and oedematous--a condition which Percival Pott, in 1760, first observed to be characteristic of extra-dural suppuration, hence the name, Pott's puffy tumour, applied to it (Fig. 193). Under these circumstances the abscess is seldom of sufficient size to cause a marked increase in the intra-cranial tension, or to give rise to localised cerebral symptoms by pressing on the brain.

When associated with a punctured wound implicating the skull, an extra-dural abscess may develop within a few days of the injury, or not till after the lapse of several weeks, and it may spread over a wide area and come to encroach on the cranial cavity sufficiently to raise the intra-cranial tension and cause symptoms of compression, or even to press upon cortical centres and produce localised paralyses. As discharge can escape from the wound in the scalp, the puffy tumour does not necessarily form.

Treatment.--When the abscess is secondary to middle ear disease, the mastoid must be opened, the eroded bone exposed, and sufficient of it removed with rongeur forceps to admit of free drainage. When the infection has spread from the frontal sinus, the skull is trephined in the frontal region, the precise site being indicated by the oedematous area in the scalp, and the diseased bone is removed. In cases of compound fracture, drainage is established by enlarging the scalp wound, and removing loose, depressed, or inflamed portions of bone; if the bone is comparatively intact, it must be trephined, and further bone is removed with rongeur forceps over the entire area in which the dura has been separated.

#Lepto-meningitis.#--If the infection spreads to the adjacent arachno-pia (localised lepto-meningitis), adhesions usually form, and shut off the infected area from the general arachno-pial space.

Pus may form among these adhesions, constituting a sub-dural abscess, and may infiltrate the superficial layers of the cortex (purulent encephalitis, or meningo-encephalitis) (Fig. 194). The symptoms are similar to those of extra-dural abscess, but may be more severe; and it is seldom possible to distinguish between them before exposing the parts by operation. The treatment is carried out on the same lines.

Acute General Lepto-Meningitis.--In bone lesions, particularly compound fractures, infection of the arachno-pia may take place before protective adhesions form, and a diffuse lepto-meningitis results. The open structure of the arachno-pial membrane favours the rapid spread of the infection, which may extend over the surface of the hemispheres, or downwards towards the base (basal meningitis), or in both directions. The process is at first attended with a copious effusion of cerebro-spinal fluid into the arachno-pial space and into the ventricles (serous lepto-meningitis), but this fluid tends to become purulent, the pus forming in a thin layer over the surface of the brain, and in the sulci between the convolutions (purulent lepto-meningitis). The membranes are congested and thickened, the veins of the arachno-pia engorged, and the superficial layers of the cortical grey matter may share in the process (encephalitis).

Clinical features.--The earliest and most prominent symptom is violent pain in the head, often referred to the frontal region, or, in cases starting from middle ear disease, to the temporal region. This is accompanied by a sudden rise of temperature, usually without an antecedent rigor; the temperature remains persistently elevated (102 deg. to 105 deg. F.), and the pulse is small, rapid, and irregular both in rate and force. The patient, especially if a child, is extremely irritable, all his sensations are hyper-acute, and he periodically utters a peculiarly sharp, piercing cry.

Vomiting of the cerebral type--that is, unattended with nausea and not related to the taking of food or to gastric disturbance--is common, and persists through the illness. The bowels are usually constipated. There is an increase in the number of leucocytes in the cerebro-spinal fluid, and organisms also are found in the fluid. As this does not occur in cerebral abscess, examination of the cerebro-spinal fluid may be useful in differential diagnosis. There is a higher leucocytosis in the blood in meningitis than in cerebral abscess.

When the inflammation is most marked over the cerebral hemisphere, there may be paralysis of the side of the body opposite to the seat of the original lesion; sometimes there is erratic rigidity of the limbs, sometimes clonic spasms of groups of muscles. The superficial reflexes disappear early on both sides; the abdominal reflexes being lost sooner than the knee-jerks. In basal meningitis, temporary squinting due to irritation of the ocular muscles, retraction of the head, and an excessively high temperature are usually prominent features. The pupils at first are equally contracted; later they become dilated and fixed. Both optic discs are oedematous and swollen.

Gradually the patient becomes unconscious, shows signs of increasing intra-cranial tension, slowing of the pulse, and laboured respiration, and the condition almost always proves fatal within three or four days.

Treatment.--The treatment consists in removing the source of infection when this is possible, but as a rule little can be done to arrest the spread of the meningitis or to ward off its effects. In cases resulting from a sub-dural abscess in relation to a compound fracture, a sinus phlebitis, or an erosion of the tegmen tympani, an attempt should be made, after exposing this, to purify and drain the meningeal spaces. Temporary relief of symptoms sometimes follows the withdrawal of cerebro-spinal fluid by repeated lumbar puncture, bleeding by leeches or cupping, or the use of an ice-bag or Leiter's tubes. The bowels should be freely moved by purgatives or enemata.

Cerebro-spinal Meningitis.--This form of meningitis, which is due to the diplococcus intracellularis, may occur sporadically, but is more frequently met with in an epidemic form. It is attended with the formation of a profuse sero-purulent exudate, which covers the brain, the cord, the nerves, and the membranes.

The clinical features are similar to those of acute general lepto-meningitis, and in sporadic cases the diagnosis is only completed by discovering the diplococcus intracellularis in the fluid withdrawn by lumbar puncture. Although recovery sometimes takes place, the disease is attended with a high mortality. In the early stages, before the exudate has become too thick, repeated lumbar puncture followed by the injection of Flexner's serum has proved beneficial. Recovery may be attended with paralysis of one or other of the cranial nerves.

CEREBRAL AND CEREBELLAR ABSCESS

#Abscess due to Middle Ear Disease.#--The most common cause of abscess in the brain is chronic middle ear disease, and the majority of cerebral abscesses are therefore situated in the temporal lobe. Some are due to direct spread from a collection of pus in relation to an erosion of the tegmen tympani, either inside or outside the dura, others to infection carried by the veins, and in this way the infective material reaches the white matter; less frequently infection from the middle ear takes place along the peri-vascular lymph spaces. Macewen has pointed out that cerebral abscess never occurs from pyogenic organisms passing from the middle ear by way of the internal auditory meatus, although lepto-meningitis may do so. Cerebral abscess is much more frequently met with in the white matter of the centrum ovale than in the cortex, and in the majority of cases the abscess is single.

The pus is often of a greenish-yellow colour, or it may be dark brown from admixture with broken-down blood-clot; in some cases it is thin and serous and contains sloughs of brain matter, and it frequently has a foetid odour. In quantity it varies from a few drops to several ounces.

The arachno-pia over an abscess usually has a turbid and milky appearance.

In an acute abscess the surrounding brain tissue is engorged and infiltrated with pus; in a chronic abscess it is condensed, and the pus may be encapsulated by the formation of a zone of young fibrous tissue round its periphery. In this condition the abscess may remain "latent," giving rise to no symptoms for many weeks or even months.

Clinical features.--The initial formation of pus in the cerebral tissue is associated with the sudden onset of severe pain in the head, shivering and well-marked cutis anserina, and vomiting of the cerebral type. The discharge from the ear usually diminishes or may even cease.

As a localised abscess develops the patient gradually passes, into a stuporous condition; he does not lose consciousness, but, his cerebration is slow, he seems unable to sustain his attention, for any length of time, and he answers questions "slowly, briefly, but, as a rule, correctly" (Macewen). The pain in the region of the ear becomes less intense, but the mastoid and temporal areas on the affected side are tender on percussion. The temperature falls, and, as a rule, remains subnormal. Rigors are unusual: their occurrence usually indicating the development of some complication such as sinus phlebitis. The pulse is full, regular, and slow (40 to 60). Vomiting frequently occurs, and the bowels are often obstinately constipated.

There is no actual paresis, but there is a "gradual diminution of the ability to apply his strength." The superficial reflexes are late of disappearing and the disturbance is unilateral. The optic discs are moderately swollen. "The face is expressionless, passive, and cloudy. It may assume a meaningless smile, with which the features are not lit; it is too mechanical" (Macewen).

Differential Diagnosis.--In the early stages it is often difficult to distinguish between meningitis and cerebral abscess. The chief points on which reliance is to be placed are that in meningitis the pulse shows an irregularity, both in rate and force, which is wanting in cases of uncomplicated abscess. In meningitis the temperature is raised, while in abscess it is persistently subnormal. The superficial reflexes, particularly the abdominal reflexes, disappear early in meningitis and the disturbance is bilateral; in abscess they are slower to disappear, and one side only is affected. Retraction of the neck, when present, is a characteristic sign of meningitis. In meningitis the optic discs are highly oedematous and are more swollen than in abscess, and the condition is equally marked on the two sides.

Localisation of Cerebral Abscess--Temporal Abscess.--The existence of middle ear disease is always presumptive evidence that the abscess is in the temporal lobe on the same side. A small abscess in this lobe may produce no localising symptoms; one of large size may press indirectly on the motor cortex, on the fibres passing through the internal capsule, or on individual cranial nerves.

It is important to observe the order in which paralysis of the opposite side of the body comes on. When it begins in the face and passes successively to the arm and leg, the pressure is on the cortical centres. When the paralysis progresses in the opposite direction--leg, arm, face--the pressure is on the nerve fibres passing through the internal capsule (Fig. 195). The paralysis may be spastic in lesions of the cortex or internal capsule; if it is flaccid the lesion is almost certainly cortical.

Motor aphasia may result from pressure on the left inferior frontal convolution; auditory aphasia from abscess in the posterior part of the superior temporal convolution. Ptosis and lateral squint, with a fixed and dilated pupil, indicates pressure on the oculo-motor nerve of the same side.

Abscess in the parietal lobe gives rise to paralysis of the face and limbs on the opposite side of the body. Abscess in the occipital lobe produces interference with the visual functions. An abscess in the frontal lobe may give rise to no localising symptoms, but if it is on the left side, the power of making co-ordinated movements may be lost--apraxia--or the motor speech centre may be implicated.

Terminal Stage.--If left to itself, a cerebral abscess usually ends fatally by causing gradually increasing stupor and coma, or by bursting, either into the ventricles or into the sub-arachnoid space, and setting up a diffuse purulent lepto-meningitis.

When the abscess bursts into the ventricles, the patient suddenly becomes much worse and dies within a few hours. "The pupils become widely dilated, the face livid, the respiration greatly hurried, and either shallow or stertorous. The temperature rises within a few hours with a bound from subnormal to 104 deg. to 105 deg. F.; the pulse from 40 or 50 per minute quickly reaches 120 and over. There are muscular twitchings all over the body, possibly associated with convulsions and tetanic seizures, and these are followed by coma and speedy death" (Macewen).

Spontaneous evacuation of a temporal abscess may take place through the middle ear.

#Cerebellar Abscess.#--Next to the temporal lobe, the cerebellum is the most common seat of abscess. Cerebellar abscess is usually due to spread of infection from a thrombosed sigmoid sinus, either directly from a sub-dural abscess formed in relation to the walls of the sinus, or by extension of the thrombotic process along the cerebellar veins. While the abscess is small, it may give rise to few symptoms, and the patient may be able to go about, but as it increases in size serious symptoms develop. There may be nystagmus, and the patient suffers from vertigo, and is unable to co-ordinate his movements. If he attempts to walk, he reels from side to side; even when sitting up in bed, he may feel giddy and tend to fall, usually towards the side opposite to that on which the abscess is situated. The head and neck are retracted, the pulse is slow and weak, and the temperature subnormal. There is frequent yawning, and the speech is slow, syllabic, and jerky. There may be optic neuritis and blindness. There is sometimes unilateral or even bilateral spastic paralysis of the limbs from pressure on the medulla oblongata. The respiration may assume the Cheyne-Stokes character, occasionally being interrupted for a few minutes, while the heart continues to beat vigorously. This arrest of respiration is especially liable to occur during anaesthesia.

Treatment.--The abscess having been localised, the skull must be opened and the pus removed.

#Abscess from causes other than Middle Ear Disease.#--From the nasal passages, infection may spread to the interior of the skull directly through the walls of the frontal, ethmoidal, or sphenoidal air sinuses, or indirectly by way of the veins, and give rise to a cerebral abscess, usually in the frontal lobe. The symptoms are similar to those of abscess following middle ear disease, but focal symptoms are seldom present. When the abscess is on the left side, apraxia and motor aphasia may be present. Spontaneous evacuation may take place by the abscess bursting into the nose through the cribriform plate.

The treatment consists in trephining through the frontal bone or through the temporal fossa, according to the site of the abscess and its seat of origin. The primary focus of infection must also be dealt with.

In infected compound fractures, an abscess may form in the cortical grey matter within a few days of the injury from direct spread of infection from the bone and membranes. This is usually associated with a spreading lepto-meningitis, the symptoms of which predominate. The condition usually proves fatal, but by opening up the original wound, removing depressed fragments of bone, and establishing drainage, the patient's life may be saved.

There is evidence that an abscess may form in the brain after a simple contusion without fracture or other external injury (Ehrenvooth).

An abscess may develop in the white matter of the centrum ovale some weeks, or even months, after an injury, particularly if a fragment of bone or a foreign body has been driven into the brain. If the infection has spread along the track of the missile, the abscess is usually near to the seat of the brain injury, but if it is due to spread of a thrombo-phlebitis it may be a considerable distance from it, even on the opposite side of the head. These chronic abscesses are usually in the parietal or frontal lobes, and as the pus is encapsulated they may remain latent for long periods, during which they may cause some degree of headache, neuralgic pains in the distribution of the trigeminal nerve, and occasional rises of temperature. When the abscess becomes active, general symptoms similar to those of other forms of abscess develop, and there may be localised paralysis of the opposite side of the body, the distribution of which depends upon whether the cortical centres or the motor fibres are implicated.

The treatment consists in opening up the original wound, removing any depressed bone or foreign body that may be present, and establishing drainage.

Bronchiectasis and other infective diseases of the lungs are less common causes of cerebral abscess, which is usually single, and may occur in any part of the brain.

Disease of the bones of the skull, such as osteomyelitis or syphilis, may be followed by cerebral abscess.

Abscesses of pyaemic origin are usually multiple, and may occur both in the cerebrum and in the cerebellum; they are not amenable to surgical treatment.

SINUS PHLEBITIS

Inflammation of the intra-cranial venous sinuses is due to the spread of infection from a local focus of suppuration; by far the most frequent cause is chronic suppuration in the middle ear. Less common sources of infection are erysipelas of the face or scalp, infective conditions of the mouth or nose, and diseases of the bones of the skull.

The organisms may reach the affected sinus directly by continuity of tissue, as, for instance, when the transverse (lateral) sinus becomes infected from a focus of suppuration in the mastoid process spreading through the bone to the sigmoid groove and involving the walls of the vessel; or they may reach it by extension of thrombosis in a tributary vein--for example, when the superior sagittal (longitudinal) sinus is infected from an anthrax pustule of the lip, which has caused thrombosis of the emissary vein that passes through the foramen caecum.

The pathological changes are the same as occur in the suppurative form of thrombo-phlebitis in the peripheral veins (Volume I., p. 285). The soft clot that forms adheres to the inflamed wall of the sinus, and, being infected with pyogenic bacteria, it soon undergoes purulent disintegration.

The infective process may spread backward along tributary vessels, and so give rise to cerebral or cerebellar abscess, or to purulent meningitis; or it may spread into the internal jugular vein and lead to the development of a diffuse purulent cellulitis along its course.

General pyaemic infection may take place from pus or bacteria getting into the circulation, either directly or by reversed flow through tributary veins. Infective emboli are liable to lodge in the lung or pleura, and set up pulmonary abscess, gangrene of the lung, or empyema.

Clinical Features.--In all cases, pain in the head, referred to the region of the affected sinus, and so severe as to prevent sleep, is an early and prominent feature. The patient is usually excited, hypersensitive, and irritable in the early stages, and becomes dull and even comatose towards the end. Rigors, followed by profuse perspiration, occur early and increase in frequency as the disease progresses. The temperature is markedly remittent, varying from 103 deg. to 106 deg. F. (Fig. 196). The pulse is rapid, small, and thready. Loss of appetite, vomiting, and diarrhoea are almost constant symptoms.

#Phlebitis of Individual Sinuses.#--The transverse (lateral or sigmoid sinus), from its proximity to the middle ear and mastoid air cells, is that most commonly affected, especially in young adults. With the onset of the phlebitis the discharge from the ear stops; there is severe pain in the ear and violent headache. The temperature rises, but shows marked remissions, and rigors are common. Vomiting is frequently present. Turgescence of the scalp veins draining into this sinus, and oedema over the mastoid, are occasionally observed; but as these signs may accompany various other conditions, they are of little diagnostic value. Not infrequently phlebitis spreads to the internal jugular vein, which may then be felt as a firm, tender cord running down the neck, and the head is held rigid, sometimes in the position characteristic of wry-neck.

Three clinical types of sinus phlebitis are recognised--pulmonary, abdominal, and meningeal--but it is often impossible to relegate a particular case to one or other of these groups. Many cases present symptoms characteristic of more than one of the types.

In the pulmonary type evidence of infection of the lungs appears towards the end of the second week, in the form of dyspnoea, cough, and pain in the side, coarse moist rales, and dark foetid sputum. Death usually takes place from gangrene of the lung. The brain functions may remain active to the end.

In the abdominal type the symptoms closely resemble those of typhoid fever, for which the condition may be mistaken. The absence of a rash and the coexistence of middle ear disease are important factors in diagnosis.

When the disease is of the meningeal type, symptoms of general purulent lepto-meningitis assert themselves, and soon come to dominate the clinical picture. Evidence of the presence of meningitis may be obtained by lumbar puncture. The mind at first is clear, but the patient is irritable; later he becomes comatose.

The prognosis is always grave, on account of the risk of general infection.

Treatment.--The primary focus of infection must first be removed, and this usually involves clearing out the middle ear and mastoid process. The sigmoid sinus is then exposed, and after any granulation tissue or pus that may be in the groove has been cleared away, the sinus is opened and the thrombus removed. With the object of preventing the dissemination of infective material, a ligature should be applied to the internal jugular vein in the neck before the sinus is opened, as was first recommended by Victor Horsley. If the phlebitis is accompanied by other intra-cranial infections, these are, of course, treated at the same time.

The superior sagittal or longitudinal sinus is liable to be infected from pyogenic lesions of the scalp. There are no symptoms that are pathognomonic, but oedema of the scalp with turgescence of its veins, epistaxis, and convulsions followed by paralysis, are those most likely to be met with.

The cavernous sinus is usually implicated by spread of the process from other sinuses--for instance, from the petrosal or transverse (lateral) sinuses--or from the ophthalmic veins in cases of orbital cellulitis. Although at first unilateral, the thrombosis usually spreads across the middle line to the sinus of the opposite side. The special symptoms--exophthalmos, oedema of the eyelids, and paralysis of the ocular nerves--are due to pressure on the structures entering the orbit.

Operative interference is seldom feasible in phlebitis of the superior sagittal (longitudinal) or cavernous sinuses.

#Intra-cranial Tuberculosis.#--Tuberculous meningitis is most frequently met with in patients below the age of twenty, and the infection takes place by the blood stream from some focus elsewhere in the body or from the spinal membranes. In cases of tuberculous disease of the middle ear infection may spread to the membranes by way of the internal auditory meatus (Macewen). The arachno-pia, especially at the base, is studded over with miliary tubercles, and an excess of fluid collects in the arachno-pial space and in the ventricles (acute hydrocephalus).

At first the symptoms of irritation of the brain predominate: severe headache, photophobia, inequality of the pupils, stiffness of the neck, cutaneous hyperaesthesia, vomiting and convulsions. Kernig's sign--pain on flexing the hip while the knee is extended, and inability to extend the knee while in the sitting posture--is present. There is usually obstinate constipation, and the abdomen is retracted. Later, signs of increased intra-cranial tension develop: unconsciousness deepening into coma, paralysis of ocular muscles, rapid pulse, Cheyne-Stokes respiration, and sometimes hyperpyrexia. An excess of mono-nuclear lymphocytes and, sometimes, tubercle bacilli may be discovered in the cerebro-spinal fluid withdrawn by lumbar puncture. The absence of the diplococcus intracellularis helps to differentiate the disease from cerebro-spinal meningitis, which it may closely simulate.

The only surgical measure that is justifiable is lumbar puncture, which often affords marked relief of symptoms, although the benefit is only temporary.

Localised tuberculous nodules sometimes develop in the brain and form definite tumours. They vary in size from a pea to a hen's egg, are rounded and encapsulated. Sometimes the centre is caseous, sometimes fibrinous or calcified. In children they are usually multiple; in adults they may be single--the so-called "solitary tubercle." They are most common in the pons, basal ganglia, and cerebellum, but occur also in the cerebral cortex and sometimes in the centrum ovale. They usually originate in the pia and invade the brain substance, but do not as a rule involve the dura. The membranes in the vicinity of the growth are often the seat of tuberculous disease.

As these nodules give rise to the same symptoms as other forms of cerebral tumour, and as their nature can be diagnosed only in exceptional cases, their clinical features and treatment are described with tumours of the brain.

#Intra-cranial Syphilis.#--Syphilitic meningitis is usually secondary to cario-necrosis of the bones of the vault or to a localised gumma of the brain. When primary, it usually affects the inter-peduncular region of the base, and takes the form of a diffuse gummatous infiltration of the membranes which gives rise to symptoms referable to the parts pressed upon, and especially paralysis of one or other of the cranial nerves. As in other intra-cranial syphilitic lesions, the symptoms show a variability in intensity which is characteristic. The diagnosis is made by the history, and the treatment is carried out on the same lines as in other syphilitic lesions.

Localised gummata are described with tumours of the brain.

CEPHALOCELES

The term "cephalocele" is applied to a protrusion of a portion of the cranial contents through a congenital deficiency in the bones of the skull. This malformation is believed to be due to an irregularity in development, whereby a portion of the primary cerebral vesicle remains outside the mesoblastic layer of the embryo. It is usually associated with adhesion of the membranes in the region of the fourth ventricle, and with internal hydrocephalus. Cephaloceles are covered by the scalp, and are most commonly met with in the occipital region and at the root of the nose; less frequently at the anterior inferior angle of the parietal bone, and in the line of the sagittal suture. Very rarely they occur at the base of the skull and project into the pharynx, the mouth, or the nose, where they are liable to be mistaken for polypi. Cephaloceles vary greatly in size, some being so small as almost to escape detection, while others are larger than a child's head. In many cases the condition is incompatible with life.

Several varieties are recognised. They are known as (1) meningocele, which consists of a protrusion of a cul-de-sac of the arachno-pial membrane, containing cerebro-spinal fluid; (2) encephalocele, in which a portion of the brain is protruded in addition to the membranes; and (3) hydrencephalocele, in which the protruded portion of brain includes a part of one of the ventricles.

Clinical Features.--The meningocele is commonest in the occipital region, where it escapes through a cleft in the bone between the foramen magnum and the occipital protuberance (Fig. 197). It forms a tense, smooth, translucent globular swelling, which may be sessile or pedunculated, and is usually covered by thin, smooth skin in which the vessels are dilated and naevoid. The tumour does not pulsate, but increases in size and tension when the child cries or coughs. It may be diminished in size or even made to disappear by pressure, and so permit of the opening in the bone being felt. This manipulation, however, may be followed by slowing of the pulse, vomiting, loss of consciousness, or convulsions.

Small meningoceles may remain stationary for a long time, or may even undergo spontaneous cure. Those of larger size usually progress till they eventually burst, and death results from the escape of the cerebro-spinal fluid or from meningitis. Infection may also occur from eczema or from excoriation of the overlying skin.

Encephaloceles are much commoner than meningoceles, and usually occur in the frontal region, where they form broad-based, elastic, and pulsatile tumours, which vary greatly in size.

The hydrencephalocele is usually met with in the occipital region, and is generally so large and associated with such great cerebral deformity as to be inconsistent with life. It does not as a rule pulsate (Fig. 198).

Cephaloceles have to be diagnosed from dermoid cysts, naevi (Fig. 199), cephal-hydrocele, and cephal-haematoma. Their recognition is seldom attended with difficulty. If the margins of the gap in the skull can be distinctly felt, or the gap in the bone can be shown by the X-rays, the diagnosis is greatly simplified.

Treatment.--Only small cephaloceles are amenable to surgical treatment; those that are large and contain brain substance are best left alone, being merely protected from irritation and infection.

While the immediate effects of operation are, on the whole, satisfactory, the ultimate results are disappointing, as the essential cause of the intra-cranial pressure persists, and the child develops hydrocephalus. The method of tapping the sac and injecting iodine has nothing to recommend it.

#Traumatic Cephal-hydrocele.#--Certain rare cases of simple fracture of the vault occurring in early childhood have been followed by the development beneath the scalp of a localised fluid swelling, which varies in size from time to time and is partly reducible by pressure. The swelling results from laceration of the membranes, and sometimes of the brain substance, so that the cerebro-spinal fluid of the sub-arachnoid space, or even of the lateral ventricle, escapes through the opening in the skull and bulges beneath the scalp. In a majority the swelling pulsates synchronously with the heart, and becomes tense on exertion. A distinct opening in the skull may sometimes be felt. When associated, as it frequently is, with mental deficiency or the occurrence of fits, the cyst may be tapped or its neck ligated (Hogarth Pringle). Otherwise it should be left alone.

HYDROCEPHALUS

An excess of cerebro-spinal fluid may collect in the arachno-pial space surrounding the brain, or in the interior of the ventricles, constituting in the former case an external, and in the latter an internal hydrocephalus. Hydrocephalus may be acute or chronic.

#Acute hydrocephalus# is practically synonymous with tuberculous meningitis, although it may result from other forms of meningeal infection. The excess of fluid is found both in the arachno-pial space and in the ventricles. This condition only calls for mention here as attempts have been made to treat it by surgical measures, such as lumbar puncture, or drainage through the occipital fossa. The results, however, have not been encouraging.

#Chronic Hydrocephalus.#--Chronic external hydrocephalus is rare, and usually results from some definite intra-cranial lesion, such as meningitis, tumour, or cerebral atrophy. It is not amenable to surgical treatment.

Chronic internal hydrocephalus, on the other hand, is a comparatively common condition. It may be of congenital origin, or may develop in young rickety children, usually as a result of some chronic inflammatory process in the membranes at the base, the choroid plexuses, or the ependyma of the ventricles, causing obstruction to the outflow of blood through the internal cerebral veins of Galen. In the acquired form the communication between the ventricles and the sub-arachnoid space, by way of the foramen of Magendie, is obstructed, so that the cerebro-spinal fluid is pent up in the ventricles and gradually distends them. The pressure causes the head to enlarge, the fontanelles to bulge, and the bones to be separated from one another, the interval between the bones being occupied by a thin translucent membrane.

The cerebral tissue is greatly thinned out, but the cerebellum and cranial nerves usually remain unaffected.

The appearance of the patient is characteristic (Fig. 200). The enormous dome of the skull surmounts a puny and preternaturally old face; the eyes are pushed downwards and forwards by the pressure on the orbital plates, and the eyebrows are displaced upwards. The head rolls helplessly from side to side; the child moans and cries a great deal; and vomiting is often a prominent symptom. In most cases the intelligence is defective, and epileptic seizures and other functional disturbances of the brain may be present.

In mild cases, especially when associated with rickets or syphilis, recovery sometimes takes place, but in the majority the condition progresses, and death results either from convulsions or from some intercurrent disease. Few hydrocephalic subjects reach adult life.

Treatment.--Hydrocephalus being a symptom rather than a disease, no method of treatment which does not remove the primary cause can be permanently curative. Anti-syphilitic treatment should be tried in the hydrocephalus of infants and young children. The rachitic element, when present, must also be treated.

In congenital hydrocephalus, as there is no blocking of the passages at the fourth ventricle, the foramina being as a rule much larger than normal, no form of drainage is beneficial. Ligation of the common carotids, one some weeks after the other, has been successful in restoring the balance which normally exists between the secretion and absorption of the cerebro-spinal fluid (H. J. Stiles). In acquired hydrocephalus, puncture of the ventricles is sometimes followed by a remarkable improvement in the symptoms, and may even result in apparent cure. An exploring needle is introduced at the lateral angle of the anterior fontanelle, to avoid the superior sagittal (longitudinal) sinus, and from a half to one ounce of cerebro-spinal fluid withdrawn. This is repeated once a week for several weeks. Continuous drainage of the fourth ventricle through an opening made in the occipital region (Parkin), and the establishment of a communication between the ventricle and sub-arachnoid space (Watson-Cheyne), or between the sub-arachnoid space of the spinal cord and the peritoneal cavity, or the retro-peritoneal space (Cushing), have been tried, with little more than temporary benefit in the majority of cases. Operative treatment, if it is to do good, must be undertaken early, before permanent changes in the brain have taken place.

#Micrencephaly.#--This condition is due to defective development of the brain, and not to premature closure of the cranial sutures and fontanelles, and as the subjects of it are mentally deficient, and often blind, deaf and dumb, the removal of segments of the skull with a view to enable the brain to develop have proved futile.

CEREBRAL TUMOURS

As a comparatively small proportion of tumours of the brain--using the term "tumour" in its widest sense--are amenable to surgical treatment, it is only necessary here to refer to those aspects of this subject that have a distinctively surgical bearing.

Various forms of growth occur in the brain, the most common being tuberculous nodules, syphilitic gumma, endothelioma, glioma, and sarcoma. Less frequently fibroma, osteoma, and parasitic, haemorrhagic, and other cysts are met with. The growth may originate in the brain tissue primarily, or may spread thence from the membranes, or from the skull. In relation to operative treatment, it is an unfortunate fact that those forms that are well defined and do not tend to infiltrate the brain tissue, usually occur at the base, where they are difficult to reach; while those that develop in more accessible regions are for the most part infiltrating growths of a gliomatous or sarcomatous nature, and are therefore irremovable.

Clinical Features.--The presence of a tumour in the brain inevitably results sooner or later in an increase in the intra-cranial tension, and to this the symptoms are chiefly due.

The earliest and most prominent of the general symptoms are severe paroxysmal headache, optic neuritis, with choked disc and limitation of the field for blue, amounting sometimes to blue-blindness (Cushing). The relative degree of neuritis in the two eyes is a reliable guide to the side on which the tumour is situated (Horsley). The symptoms are seldom absent, and are common to all forms of tumour, wherever situated. Vomiting, which is without relation to the taking of food and is usually unattended by nausea, is a characteristic symptom when present, but it is wanting in two-thirds of the cases (Cushing). Vertigo, general convulsions, and signs of mental deterioration are also present in a considerable proportion of cases.

In addition, certain localising symptoms may be present. When, for example, the tumour is situated in the cortex of the Rolandic area, attacks of Jacksonian epilepsy, preceded by an aura, which is usually referable to the centre primarily implicated, are common. The group of muscles first involved, and the order in which other groups become affected, are important localising factors. As the tumour increases in size, these irritative phenomena are replaced by localised paralyses. The tactile and muscular sensations are also disturbed, and motor and sensory aphasia may be present. In some cases localised tenderness on percussing the skull may be of assistance in indicating the site of the tumour.

When the tumour is sub-cortical, that is, in the centrum ovale, there are no Jacksonian spasms, the motor paralysis is more widespread, and sensation also is lost on the opposite side of the body. There is no special tenderness on percussion. It is not always possible, however, to distinguish between cortical and sub-cortical tumours, and in many cases both areas are invaded.

Tumours situated in the region of the internal capsule, and in the deeper parts of the brain, are not attended with Jacksonian spasms, paralysis develops more rapidly than in cortical and sub-cortical tumours, and there is complete loss of sensation on the opposite side of the body. The cranial nerve-trunks also are liable to be pressed upon.

Tumours and cysts in the cerebellum give rise to symptoms similar to those of cerebellar abscess (p. 381).

Tumours in the cerebello-pontine angle, in addition to the special symptoms associated with cerebellar lesions, give rise to symptoms of interference with nerve-roots of the same side. The facial and acoustic nerves are most frequently affected, resulting in facial weakness, tinnitus, loss of perception for high-pitched notes, as tested by Galton's whistle, or absolute unilateral deafness. Any of the other cranial nerves from the fifth to the twelfth may be either irritated or paralysed. Pressure on the pons may produce hemiplegia of the opposite side, with spasticity and exaggeration of reflexes. Sudden death may occur from crowding of the cerebellum into the foramen magnum.

With the growth of the tumour the symptoms become aggravated, the optic neuritis is followed by optic atrophy and blindness, the patient gradually becomes stuporous, and finally dies in a state of coma. The severity of the symptoms depends to a large extent on the rapidity of growth of the tumour; thus an osteoma growing slowly from the inner table of the skull and implicating the brain may reach a considerable size without producing cerebral symptoms, while a comparatively small sarcoma or syphilitic gumma of rapid growth may endanger life. A sudden and serious aggravation of symptoms may result from haemorrhage into a soft tumour, such as glioma.

The diagnosis of the pathological nature of a cerebral tumour is generally "hardly more than a guess" (Gowers). At the same time it may be borne in mind that syphilitic gummata occur in adults, from forty to sixty years of age, who have suffered from acquired syphilis, and who may present other evidence of the disease. They tend to increase somewhat rapidly. A negative Wassermann reaction does not necessarily exclude a diagnosis of brain syphilis. Severe nocturnal pain which interferes with sleep is often a prominent symptom. Gummata are generally situated on the surface of the brain; they often originate in the dura mater, and when exposed are easily enucleated. Improvement in the symptoms may follow the administration of iodides and mercury, or organic arsenical salts of the salvarsan group, but in many cases the growth is very resistant to anti-syphilitic treatment.

Tuberculous masses occur most frequently in children and adolescents, and other signs of tuberculosis are usually present. The cerebellum is a common seat of these tumours, and they are often multiple. Their growth may be rapid at first, and then become arrested for a time. Spasmodic growth of a tumour strongly suggests its tuberculous nature, and superadded signs of basal meningitis confirm the diagnosis.

Endothelioma grows from the dura mater, and in so far as it is a well-defined and non-infiltrating growth it lends itself to removal by operation. Unfortunately, however, it is usually located at the base of the brain and is not readily accessible.

Glioma is usually met with in the young; it tends to grow slowly at first, but may take on a rapid growth at any time, and haemorrhage is liable to occur into the substance of the tumour, causing a sudden aggravation of the symptoms.

Sarcoma occurs between puberty and middle life; it grows slowly, and compresses rather than destroys the brain tissue. It is sharply defined from the surrounding cerebral tissue, and is therefore more favourable for operation than glioma.

The prognosis is grave in all forms of brain tumour. Even in syphilitic growths, although the more urgent symptoms may be ameliorated by the use of drugs, recurrence is liable to occur, and the structural changes induced in the cerebral tissue, and the contraction of the cicatrix which results, may permanently interfere with the functions of the brain, or may induce Jacksonian epilepsy. Tuberculous tumours also may become arrested, and may cease for a time to cause symptoms, but permanent cure is extremely rare. We have known a sarcoma to recur as late as five years after removal. Death sometimes occurs suddenly from haemorrhage, from acute oedema, or from implication of vital centres.

Treatment.--It is to be borne in mind that gummatous growths in the brain are seldom influenced to any extent by anti-syphilitic remedies, and time should not be wasted in trying this form of treatment.

The question of removal by operation arises in cases in which there is reason to believe that the tumour is situated near the surface of the brain and that it is circumscribed and of moderate size. Unfortunately it is only in a small proportion of cases that these conditions are present and can be recognised before opening the skull.

In many cases in which there is no hope of being able to remove the tumour, it is advisable to relieve symptoms due to excessive intra-cranial tension, such as blindness, severe headache, and persistent vomiting, by performing a "decompression operation" (Operative Surgery, p. 108). The relief that follows such operations is often remarkable.

Lumbar puncture, frequently repeated, has also been practised for the relief of tension in inoperable cases, but it is not free of danger and is not to be looked upon as a substitute for a decompression operation.

When surgical treatment is contra-indicated, all that can be done is to palliate the symptoms by bromides, opium, phenacetin, caffein, and other drugs.

#Tumours of the Pituitary Body# or #Hypophysis Cerebri#.--The tumours most frequently met with in the pituitary body are of the nature of adenoma with hyperplasia and cystic degeneration; carcinoma and sarcoma also occur. They develop slowly and give rise to comparatively slight increase in the intra-cranial tension. When the anterior lobe is implicated and there is a pathological increase in the functional activity of the gland (hyperpituitarism), signs of acromegaly may ensue. Diminution of function (hypopituitarism) is attended with infantilism, a rapid deposition of fat in the subcutaneous tissue, and a decrease or loss of the genital functions. In women, amenorrhoea is an early and constant symptom. Intense drowsiness is a marked feature in some cases.

From their position close to the back of the optic chiasma these growths affect the fibres passing to the nasal half of each retina, and so give rise to bilateral temporal hemianopsia, and although there is no choked disc, the optic nerves undergo primary atrophy from pressure, and there is failure of sight.

Marked temporary benefit has followed the administration of thyreoid extract. Operative treatment has been successful in a number of cases, but as the anterior lobe is essential to life, the operation is merely directed towards the relief of pressure on the optic chiasma with a view to preventing loss of vision. We have seen marked relief follow a temporal decompression operation.

#Epilepsy.#--The surgical aspects of Jacksonian epilepsy following head injuries have already been considered (p. 358). For the cure of those forms of epilepsy in which there is no gross lesion of the brain, numerous surgical procedures have been suggested, but from none of these have the results been encouraging.

#Hernia Cerebri.#--This term is applied to a protrusion of brain substance through an acquired opening in the skull and dura mater, such as may result from a compound fracture or a gun-shot wound. The protrusion is due to increased intra-cranial tension, and is almost invariably associated with infection of the brain and its membranes, and with the presence of a foreign body or fragments of bone. Other things being equal, a hernia is more likely to occur through a small than through a large opening in the skull.

So long as the extruded portion of brain matter is small, it pulsates, but as it increases in size and is pressed upon by the edges of the opening through which it escapes, the pulsation ceases, and the herniated portion may become strangulated and undergo necrosis.

In cases of compound fracture, and in other conditions associated with necrosis of bone, masses of redundant granulation tissue growing from the soft parts outside the skull may simulate a hernia cerebri.

The treatment consists in counteracting the septic infection by purifying the protruding mass, and if necessary by enlarging the opening in the skull with rongeur forceps to admit of the removal of foreign bodies or bone fragments and to relieve the inter-cranial tension. Steps must also be taken to prevent meningitis, which, if it occurs, is usually fatal. Pressure over the hernia, with the object of returning it to the skull, is to be avoided, and the herniated portion should not be cut away unless it is sloughing, or has become pedunculated. It may be got rid of by painting it with 40 per cent. formalin, which causes a dry, horny crust to form on the surface; this is picked off, and the formalin re-applied.

After the hernia has disappeared and the wound is aseptic, steps should be taken to close the gap in the skull. This may be done by an osteo-plastic operation in which a flap, comprising a segment of the outer table, is raised from an adjacent part of the skull and placed in the gap; or by transplanting a portion of periosteum-covered bone from the scapula, tibia, or other suitable source. An alternative method is to implant a plate of celluloid, silver or other metal, or a portion of the fascia lata, in the gap. When a permanent hole is left in the bone, the patient should wear over it a leather or metal shield to protect the brain.

The protrusion of brain resulting after a decompression operation deliberately performed for the relief of intra-cranial tension, unless it becomes infected, has nothing in common with a hernia cerebri.

SURGICAL AFFECTIONS OF THE CRANIAL NERVE

Irritation, or paralysis, of one or more of the cranial nerves may result from lesions implicating their centres or trunks.

When the trunk of the nerve is affected, the paralysis is on the same side as the lesion, and is of the lower neurone type; when the cortical centre or the upper axons are involved, it is on the opposite side, and is of the upper neurone type (p. 334). The lesions of the cerebral centres with which nerve symptoms are most frequently associated are: laceration of the brain, haemorrhage, meningitis, tumour, and syphilitic gumma.

The nerve-trunks may be contused or torn across, especially in basal fractures which traverse their foramina of exit; blood may be effused into their sheaths as a result of injuries not attended with fracture; or they may be pressed upon by an inflammatory effusion, a tumour, a gumma, or an aneurysm invading the base of the skull. When the nerve is merely contused, or pressed upon by blood-clot, the paralysis tends to pass off in the course of a few days. When it is torn across, or compressed by a new growth, the paralysis is permanent. In some traumatic cases paralysis does not come on until a few days after the injury, and is then due either to gradually increasing pressure from blood-clot, or more probably to the onset of meningitis or of ascending neuritis.

I. The branches of the Olfactory Nerve may be ruptured as they pass through the cribriform plate in fractures implicating the anterior fossa of the skull, and there results complete and permanent loss of smell (anosmia). Haemorrhage into the nerve sheath or contusion of the nerve may cause a transitory loss of smell. The trunk of the nerve may be implicated also in tumours and meningitis in the anterior fossa. In all cases in which anosmia results there is also interference with the power of recognising different flavours, thus greatly impairing the sense of taste.

II. Optic Nerve.--Temporary paralysis of one or both optic nerves is a comparatively common result of traumatic effusion of blood into their sheaths; the resulting blindness may pass off in a few days, or may last for some weeks. When a large effusion takes place, the prolonged pressure on the nerve may result in optic atrophy and permanent blindness. Complete severance of the nerve by a bullet, the point of a sharp instrument, or a fragment of bone, results in loss of sight in the eye on the same side. In cellulitis of the orbit, intra-orbital tumour, gumma and aneurysm in the region of the cavernous sinus, also, the optic nerve may be implicated.

Lesions implicating the cortical centre for sight in the occipital lobe give rise to hemianopia--that is, loss of sight in the lateral halves of the fields of vision of both eyes--colour-blindness, subjective sensations of light and colour, and other eye symptoms.

Double optic neuritis, followed by optic atrophy, is one of the most constant effects of the growth of a tumour within the skull, and is not uncommon in cases of cerebral abscess and meningitis. Pressure on the optic chiasma, for example by a tumour of the pituitary body, is associated with bilateral temporal hemianopsia.

III. Oculo-Motor Nerve.--One or more of the branches of this nerve may be compressed by extravasated blood, or be contused and lacerated in fractures implicating the region of the sphenoidal fissure. Fixed dilatation of one pupil may result from pressure by blood-clot, without other functional disturbance of the nerve. A tumour or an aneurysm growing in this region also may press upon the nerve. Sometimes both nerves are involved--for example, in fracture implicating both sides of the anterior fossa, and in tumours, particularly gumma, growing in the region of the floor of the third ventricle. In lesions of the cerebral hemispheres the third nerve is frequently paralysed. Its cortical centre lies in close proximity to the centre for the face (Fig. 179).

The most prominent symptoms of complete paralysis are ptosis or drooping of the upper eyelid, lateral strabismus, and slight downward rotation of the eye with diplopia. There are also dilatation of the pupil from paralysis of the circular fibres of the iris, and loss of accommodation and reaction to light from paralysis of the ciliary muscle.

Paralysis of the muscle supplied by the third nerve is frequently associated with paralysis of other ocular muscles. When all the muscles of the eye are paralysed, the condition is known as "opthalmoplegia externa"; it is usually due to syphilitic disease in the floor of the third ventricle.

IV. The Trochlear or Patheticus Nerve, which supplies the superior oblique muscle, may suffer in the same way as the oculo-motor nerve. When it is paralysed, there is defective movement of the eye downward and medially, and the patient may complain of diplopia when he looks downward.

V. Trigeminal Nerve.--The most important surgical affection of this nerve is "trigeminal neuralgia," which has already been described (Volume I., p. 373). One or other of the divisions of the nerve may be torn in fractures of the base of the skull, and there results anaesthesia in the area supplied by it. In fractures crossing the apex of the petrous portion of the temporal bone, the great and small superficial petrosal nerves may be ruptured, and the soft palate and uvula are paralysed and there is difficulty in swallowing; there are also painful sensations in the ear. When the ophthalmic division is implicated, the conjunctiva is rendered insensitive, and conjunctivitis, which may be followed by ulceration of the cornea, results from exposure to dust and other foreign bodies, which, on account of the anaesthetic condition of the eye, are allowed to remain and cause irritation.

VI. Abducens Nerve.--This nerve, which supplies the lateral rectus muscle, has the longest course within the skull of any of the cranial nerves. In spite of this fact, it is comparatively seldom torn in basal fractures; but it is prone to be pressed upon by tumours, gummas, or aneurysms in the region of the base of the brain. When it is paralysed, medial strabismus results.

VII. Facial Nerve.--Paralysis of the facial muscles, more or less complete, is the most characteristic symptom of lesions of this nerve.

Paralysis of the Cerebral Type.--When the fibres of the nerve are implicated in any part of their course between the cortical centre and the nucleus in the lower part of the pons, the paralysis is of the upper neurone (cerebral) type. It affects the side of the face opposite to that of the lesion, and the defective movement is more marked in the lower than in the upper half of the face.

This form of facial paralysis may be due to the pressure of an intra-cranial tumour, abscess, or haemorrhage, or to degenerative processes in the cerebral tissue, and as a rule other cranial nerves are also affected. Its recognition is chiefly of diagnostic and localising importance.

Paralysis of the Peripheral Type.--When the trunk of the nerve is implicated between the pontine nucleus and its peripheral distribution, the paralysis is of the lower neurone (peripheral) type, the muscles on the same side as the lesion being flaccid and atrophied.

The majority of cases are of the so-called "rheumatic" variety, and are attributed to exposure to cold. Others result from fractures implicating the middle fossa of the skull, or are associated with chronic suppuration in the middle ear.

In fractures passing across the petrous temporal, the nerve may be torn at the time of the injury, or may become pressed upon by a traumatic effusion or by callus later, but considering the frequency of these fractures it is comparatively seldom damaged.

Suppurative disease of the middle ear is a more common cause of facial paralysis. The nerve, as it traverses the facial canal (aqueductus Fallopii), may be pressed upon by inflammatory effusions or granulations, or may be destroyed by the suppurative process, particularly in young children, as in them the osseous wall of the aqueduct is very thin. It may also be involved in tuberculous and in malignant disease of the middle ear.

The nerve may be injured also in the course of operations on the mastoid or middle ear, or in the removal of tumours or glands in the parotid region. As the nerve breaks up into numerous branches soon after it leaves the stylo-mastoid foramen, the paralysis may be confined to one or more of its branches.

Temporary paralysis may result from inflammatory conditions such as parotitis, or from blows or pressure over the nerve, for example by the forceps in delivery.

Symptoms.--In complete unilateral facial paralysis (Bell's paralysis) the affected side of the face is expressionless and devoid of voluntary or emotional movement. The muscles are flaccid, the cheek is flattened and smooth, all its folds and wrinkles being obliterated. When the patient speaks or smiles, the face is drawn to the sound side (Fig. 201). The eye on the affected side cannot be closed, and on making the attempt the eyeball rolls upwards and outwards. The lower lid droops, the patient cannot wink, and the conjunctiva therefore becomes dry, and is irritated by exposure to cold and dust. The tears run over the cheek. From paralysis of the buccinator muscle there is inability to whistle or to puff out the cheeks and food collects between the cheek and the gums. The orbicularis oris being also paralysed, the patient is unable to show his upper teeth, and the labial consonants are pronounced indistinctly. The sense of taste is often impaired from involvement of the chorda tympani nerve.

When the paralysis is bilateral, the symmetrical appearance of the face renders the condition liable to be overlooked.

Treatment.--In addition to removing the cause, when this is possible, recovery of function may be promoted by the administration of drugs, such as potassium iodide, strychnin, or iron, by the application of blisters, or by massage and electricity. These measures are most useful in cases due to blows or exposure to cold. When the nerve is accidentally divided in the course of an operation on the face, it should immediately be sutured. So long as the electrical reactions of the affected muscles indicate an incomplete lesion, recovery may be confidently expected (Sherren). When the reaction of degeneration is present and the paralysis has lasted for more than six months, there is little hope of recovery, and recourse should be had to operation, to restore the function of the nerve by grafting its distal end on to the trunk of the hypoglossal nerve. To prevent paralysis of the tongue the lingual nerve may be divided, and its proximal end anastomosed with the distal end of the hypoglossal.

The facial may be grafted on the accessory nerve, but the associated movements of the face which then accompany movements of the shoulder often prove inconvenient.

Facial Spasm.--Clonic contraction of the facial muscles (histrionic spasm) occasionally results from irritative lesions in the cortex or pons. Sometimes all the muscles are involved, sometimes only one, for example the orbicularis oculi (palpebrarum)--blepharospasm. This condition may be induced reflexly from irrigation of the trigeminal nerve, notably of branches that supply the nasal cavities and the teeth.

The treatment consists in removing any source of peripheral irritation that may be present, in employing massage, and in administering nerve tonics, bromides, and other drugs. In severe cases, the facial nerve may be stretched with benefit, either at its exit from the stylo-mastoid foramen or on the face.

VIII. Acoustic or Auditory Nerve.--The acoustic nerve is liable to be damaged along with the facial in tumours of the cerebello-pontine angle, and in fractures which traverse the internal auditory meatus. Both nerves also may be torn across just before they enter the meatus in severe brain injuries apart from fracture. Complete and permanent deafness results. Effusion of blood into the nerve sheath, or into the internal or middle ear, causes transitory deafness, and the patient suffers from noises in the ear, giddiness, and interference with equilibration.

IX. The Glosso-pharyngeal Nerve is comparatively seldom injured. When it is compressed by a tumour in the region of the medulla, there is interference with speech and deglutition, ulcers form on the tongue, and oedema of the glottis may supervene.

X. The Vagus or Pneumogastric Nerve is seldom injured within the cranial cavity.

In the neck, it is liable to be divided or ligated in the course of operations for the removal of malignant or tuberculous glands, for goitre, or for ligation of the common carotid. Division of the nerve on one side, or even removal of a portion of it, is not as a rule followed by any change in the pulse or respiration. If it is irritated, however, for example by being grasped with an artery forceps, there is inhibition of the heart, and if it is accidentally ligated, there may be persistent vomiting.

Division of the main trunk, or of its recurrent branch on one side, results in paralysis of the corresponding posterior crico-arytaenoid muscle--the muscle that opens the glottis. This condition is known as unilateral abductor paralysis, and is accompanied by interference with inspiration and phonation. If both nerves are divided, bilateral abductor paralysis results: the vocal cords flap together, producing a crowing sound on inspiration and embarrassment of breathing, and tracheotomy may be necessary to prevent asphyxia.

The vagus and recurrent nerves have been successfully sutured after having been divided accidentally.

XI. Accessory or Spinal Accessory Nerve.--This nerve is seldom damaged within the skull. It supplies the sterno-mastoid and trapezius; but as these muscles usually have an additional nerve supply from the cervical plexus, the accessory may be divided, or a considerable portion of it resected, as, for example, in the treatment of spasmodic torticollis, without any serious disablement resulting. It is liable to be accidentally divided in excising malignant or tuberculous glands in the neck. When, however, the accessory is the only source of supply to these muscles, its division is followed by considerable disablement, which appears to depend almost entirely on the paralysis of the trapezius. The head is inclined slightly forward, the shoulder is depressed, the arm hangs heavily by the side and is slightly rotated forward, the scapula is drawn away from the spine and rotated on its horizontal axis, and there is slight cervical scoliosis with the concavity towards the affected side. The trapezius is markedly wasted, and is, therefore, less prominent in the neck than normally, and the functions of the arm and shoulder are impaired, especially in making overhead movements. In time other muscles compensate in part for the loss of the trapezius.

When divided accidentally, the nerve should be immediately sutured. Even when the paralysis has lasted for some time, secondary suture should be attempted; if this is impossible, the peripheral end should be anastomosed with the anterior primary divisions of the third and fourth cervical nerves (Tubby). Massage, electricity, and the administration of tonics are also indicated.

XII. Hypoglossal Nerve.--This nerve has been ruptured in fractures passing through the canalis hypoglossi (anterior condylar foramen). It is also liable to be divided in wounds of the submaxillary region--for example, in cut throat, or during the operation for ligation of the lingual artery, or the removal of diseased lymph glands.

The paralysed half of the tongue undergoes atrophy. When the tongue is protruded, it deviates towards the paralysed side, being pushed over by the active muscles of the opposite side. Speech and mastication are interfered with, the tongue feeling too large for the mouth; in time this disability is to a large extent overcome.

#The Cervical Sympathetic.#--The cervical sympathetic cord and its ganglia may be injured in the neck by stabs or gun-shot wounds, or in the course of deep dissections in the neck; and in injuries of the lower part of the cervical enlargement of the spinal cord (p. 417) or of the first dorsal nerve root.

Paralysis of the cervical sympathetic is characterised by diminution in the size of the pupil on the affected side. The pupil does not dilate when shaded, nor when the skin of the neck is pinched--"loss of the cilio-spinal reflex." The palpebral fissure is smaller than its fellow, and the eyeball sinks into the orbit. There is anidrosis or loss of sweating on the side of the face, neck, and upper part of the thorax, and on the whole upper extremity of the affected side.

XV. DISEASES OF THE CRANIAL BONES

Suppurative periostitis and osteomyelitis--Tuberculosis-- Syphilis--Tumours.

#Suppurative Periostitis and Osteomyelitis.#--These conditions may be the result of infection through the blood stream, but as a rule they follow upon a breach of the surface caused by a wound, a severe burn as in epileptics, a tertiary syphilitic ulcer, or a compound fracture that has become infected. Sometimes they follow suppuration in the middle ear and mastoid or in the frontal sinus, and epithelioma and rodent cancer that has ulcerated and become infected after spreading from the face towards the vertex. They are occasionally associated with acute cellulitis of the scalp. When the infection is blood-borne suppuration occurs on both aspects of the bone--a point of importance in treatment.

The illness is usually ushered in by a rigor, and this is soon followed by other signs of suppuration--high temperature, pain and tenderness, and the formation of a fluctuating swelling in relation to the bone. When pus forms between the bone and the dura, there is a characteristic oedema of the overlying area of the scalp--spoken of as Pott's puffy tumour--which is of value as indicating the extent of the disease in the bone, and of the collection of pus between it and the dura. When suppuration occurs under the pericranium, an incision gives exit to a quantity of pus, and exposes an area of bare bone. If the incision is made early, this bone may soon be covered by granulations and recover its vitality; but if operation is delayed, it usually undergoes necrosis. The sequestrum that forms includes, as a rule, only the outer table, but in some cases the whole thickness of the bone undergoes necrosis. In either case the separation of the sequestrum is an exceedingly slow process, and is not accompanied by the formation of new bone. When the whole thickness of the skull is lost, there may be a protrusion of the contents of the skull--hernia cerebri; should the patient survive, the gap becomes filled in by a dense fibrous membrane which is fused with the dura mater.

Serious complications, in the form of meningitis, cerebral abscess, sinus phlebitis, and general pyaemia, are liable to develop at any time during the progress of the infection, and we have seen pyaemia develop after the suppuration in the skull had been recovered from.

Treatment.--Early, free, and, if necessary, multiple incisions are indicated to admit of disinfection of the affected area, and of the establishment of drainage. If the symptoms point to suppuration having occurred between the bone and the dura, the skull should be trephined and further bone removed with the rongeur forceps as may be required.

Time may be saved by separating the sequestrum with the aid of an elevator or sharp spoon, or by chiselling away the dead part till healthy vascular bone is reached.

#Tuberculosis# of the cranial vault is usually met with in children. The disease commences in the diploe, and results in the formation of a central sequestrum, around and beneath which the tuberculous process spreads. Granulations form between the skull and the dura, and on the outer aspect lifting up the pericranium. The sequestrum is slowly thrown off, and when separated is circular like a coin and presents worm-eaten edges.

A circumscribed, tender swelling forms, at first yielding an obscure sensation of fluctuation, but later, when the pus is no longer confined under the pericranium, assuming the characters of a cold abscess, which gradually becomes superficial, and eventually bursts through the scalp, forming one or more sinuses.

The abscess should be laid open, all tuberculous granulations scraped away, and the sequestrum removed, with the aid of the chisel if it has not already become loose. On inserting the finger through the opening, it appears to penetrate to an alarming extent; this is due to the accumulation of tuberculous material between the skull and the dura mater, depressing the latter. After healing is completed, a depression or gap in the bone remains.

#Syphilis.#--Syphilitic affections occur during the tertiary period of the disease, and usually implicate the frontal and parietal bones (Fig. 202). They are described in Volume I., p. 462.

#Tumours.#--Osteoma of the skull has been described with diseases of bone (Volume I., p. 481).

Sarcoma.--All forms of sarcoma are met with, implicating the bones of the skull. They may originate in the pericranium, in the diploe, or in the dura mater, and usually involve the bones of the vault. They sometimes occur in children (Fig. 203).

The tumour grows chiefly towards the surface, but it also tends to invade the cranial cavity, and may thus assume the shape of a dumb-bell. Its growth is usually rapid, and results in the formation of a diffuse soft swelling, which sometimes pulsates, and sooner or later fungates through the skin. On account of its rapid growth the tumour is liable to be mistaken for an abscess, and in some cases the nature of the disease is only discovered after making an exploratory incision, and finding that the finger passes through a softened area in the bone.

When the cranial cavity is encroached upon, signs of compression ensue. After the tumour has fungated, infective complications within the skull are liable to develop. In all cases the prognosis is extremely unfavourable.

If diagnosed sufficiently early, an attempt may be made to remove the tumour, but often the operation has to be abandoned, either on account of the haemorrhage which attends it, or because of the extent of the disease.

The bones of the skull may become the seat of secondary growths by the direct spread of cancer from the soft parts, e.g. rodent cancer (Fig. 204), or by metastasis of cancer or sarcoma from distant parts of the body, or of thyreoid tumours. Metastatic cancer would appear to be conveyed by the blood stream; it may occur in a diffuse form--cancerous osteomalacia--softening the calvaria so that at the post-mortem examination it may be removed with the knife instead of the saw; or it occurs in a discrete or scattered form, and then the macerated skull presents a number of circular and oval perforations.

XVI. THE VERTEBRAL COLUMN AND SPINAL CORD

Surgical Anatomy--Injuries of the spinal cord: Concussion; Traumatic haematorrachis; Traumatic haematomyelia; Total transverse lesions at different levels; Partial lesions; "Railway spine"--Injuries of the vertebral column: Sprain; Isolated dislocation of articular processes; Isolated fracture of arches and spinous processes; Compression fracture of bodies--Traumatic spondylitis--Fracture-dislocation--Penetrating wounds.

#Surgical Anatomy.#--The veretebral column is the central axis of the skeleton, and affords a protecting casement for the spinal cord.

The spine is movable in all directions--flexion, extension, lateral flexion, and rotation around the long axis of the column. Flexion is accompanied by compression of the intervertebral discs, and by a slight forward movement of each vertebra on the one below it. This forward movement is checked by the tension of the ligamenta flava which stretch between the laminae.

In the infant, the spine is either straight or presents one long antero-posterior curve with its convexity backwards. With the assumption of the erect posture the normal S-shaped curve is developed, the cervical and lumbar segments arching forward, while the thoracic and sacral segments arch backward.

Through the skin it is often difficult to identify with certainty the individual spinous processes. The spine of the seventh cervical vertebra,--vertebra prominens--and that of the first thoracic, are those most readily felt. While the arm hangs by the side, the root of the spine of the scapula is opposite the third thoracic spine, and the lower angle of the scapula is on the same level as the seventh. The twelfth thoracic vertebra may be recognised by tracing back to it the last rib. A line joining the highest points of the iliac crests crosses the fourth lumbar spine; and the second sacral spine is on the same level as the posterior superior iliac spine. The bodies of the upper cervical vertebrae may be felt through the posterior wall of the pharynx. The cricoid cartilage corresponds in level to that of the lower border of the sixth cervical vertebrae and its transverse process.

It is important for surgical purposes to bear in mind that most of the spinous processes do not lie on the same level as their corresponding bodies. The tips of the spines of the cervical and first two or three thoracic vertebrae lie, roughly speaking, opposite the lower edge of their respective bodies; those of the remaining thoracic vertebrae lie opposite the body of the vertebrae below; while the spines of the lumbar vertebrae lie opposite the middle of their corresponding bodies.

The vertebral canal contains the spinal cord so suspended within its membranes that it does not touch the bones, and is not disturbed by the movements of the vertebral column.

The membranes of the cord are continuous with those of the brain. The arachno-pia invests the cord and furnishes a sheath to each of the spinal nerves as it passes out through the intervertebral foramen. The arachno-pial space is filled with cerebro-spinal fluid, which forms a water-bed for the cord, continuous with that at the base of the brain. The dura mater constitutes the enveloping sheath of the cord. It hangs from the edge of the foramen magnum as a tubular sac, and is connected to the bones only opposite the intervertebral foramina, where it is prolonged on to each spinal nerve as part of its sheath. Between the dura and the bony wall of the canal is a space filled with loose areolar tissue and traversed by large venous sinuses. The dura extends as far as the upper edge of the sacrum.

The spinal cord extends from the foramen magnum to the level of the disc between the first and second lumbar vertebrae. The cervical enlargement, which includes the lower four cervical and the upper two thoracic segments, ends opposite the seventh cervical spine. The lumbar enlargement lies opposite the last three thoracic spines.

One pair of spinal nerves leaves each "segment" of the cord. On leaving the cord the nerves incline slightly downwards towards the foramina by which they make their exit from the canal. The obliquity of the nerves gradually increases, till in the lower part of the canal--from the second lumbar vertebra onward--they run parallel with the filum terminale and together constitute the cauda equina.

It is to be borne in mind that owing to the fact that the cord is relatively shorter than the canal, the tips of the spinous processes lie a considerable distance lower than the segments of the cord with which they correspond numerically. To estimate the level of the segment of the cord which is injured: in the cervical region add one to the number of the vertebra counted by the spines; in the upper thoracic region add two, in the lower thoracic region add three, and this will give the corresponding segment. The lower part of the eleventh thoracic spinous process and the space below it are opposite the lower three lumbar segments. The twelfth thoracic spinous process and the space below it are opposite the sacral segments (Chipault).

Functions.--The essential function of the spinal cord is to transmit motor and sensory impulses between the brain and the rest of the body. The general course of the fibres by which these impulses travel has already been described (p. 331).

In the grey matter there are groups of nerve-cells--"centres"--which govern certain reflex movements. The most important of these--the centres for the rectal, the vesical, and the patellar reflexes--are situated in the lumbar enlargement.

In the great majority of cases of spinal disease or injury coming under the notice of the surgeon the symptoms are bilateral, that is, are of the nature of paraplegia, and the whole of the body below the level of the segment affected is involved in the paralysis. Lesions affecting only one-half of the cord are rare and give rise to symptoms which are exceedingly complicated. When the lesion implicates the nerve-roots only, the symptoms are confined to the area supplied by the affected nerves.

INJURIES OF THE SPINAL MEDULLA OR CORD

As the clinical importance of a spinal injury depends almost entirely on the degree of damage done to the cord, we shall consider injuries of the cord before those of the vertebral column. They will be described under the headings: Concussion of the Cord; Traumatic Spinal Haemorrhage; Total Transverse Lesions; Partial Lesions of the Cord and Nerve Roots; and "Railway Spine."

#Concussion of the Spinal Cord.#--Concussion of the cord is now regarded as a definite entity closely resembling concussion of the brain. In some cases, the underlying lesion is of a temporary character, usually in the form of a vascular disturbance such as oedema or vascular engorgement, and possibly an arterial anaemia; in other cases there is definite evidence of injury, of the nature of contusion, minute haemorrhages and blood-staining of the cerebro-spinal fluid. It must be clearly stated, that concussion of the cord may be attended with an immediate arrest of all its functions closely resembling the condition following upon complete crushing of the cord--total transverse lesion,--and it may be impossible to differentiate between the two conditions until two or more days have elapsed after the accident; it is usual, however, in concussion, as contrasted with crushing of the cord, that although motor conduction may be completely abolished, sensation is only impaired and evidence of sensory conduction can usually be elicited. If the lesion is merely a concussion, the functions of the cord will be restored within a day or two, first to full sensation and then to full motor power.

A classical instance is that of a late Governor-General of India, who on being thrown in the hunting-field was found to be paralysed in all four extremities; Paget diagnosed a total transverse lesion of the cervical cord with the necessary inference that it would inevitably have a fatal termination. The fact that the patient recovered completely, and was later able to fill two Viceroyalties, proved that the lesion must have been of the nature of a concussion of the cord.

The treatment consists in adopting the same measures as in crushing of the cord, while careful watch is observed for the signs of recovery of conduction. The usual order of recovery is first the reflexes, then sensation, and lastly, the motor functions.

#Traumatic Spinal Haemorrhage.#--Haemorrhage into the vertebral canal is a common accompaniment of all forms of injury to the spine, but the lower cervical region is the common seat of the severe type of haemorrhage resulting from acute flexion of the spine such as occurs especially in a fall on the head from a horse or a vehicle in motion. The blood may be effused around the cord--between it and the dura--(extra-medullary), or into its substance (intra-medullary).

Extra-medullary Haemorrhage--Haematorrachis.--The symptoms associated with extra-medullary haemorrhage are at first of an irritative kind--muscular cramps and jerkings, radiating pains along the course of the nerves pressed upon, and hyperaesthesia. It is only when the blood accumulates in sufficient quantity to exert definite pressure on the cord that symptoms of paralysis ensue, and it is characteristic of extra-medullary haemorrhage that the paralysis comes on gradually. When the effusion is in the cervical region--the commonest situation--the arms are more affected than the legs. The paralysis of the arms is of the lower neurone type, and the muscles are flaccid and undergo atrophy; the legs may exhibit a more complete degree of paralysis of the upper neurone type, with exaggeration of the knee-jerks. Blood may trickle down the canal and collect at a level lower than that of the lesion which causes the bleeding, and produce paralysis which slowly spreads from below upwards--gravitation paraplegia (Thorburn). There is blood in the cerebro-spinal fluid.

The treatment is on the same lines as in total transverse lesions. When there is evidence of progressive pressure on the cord, the blood is removed by spinal puncture if possible, or by laminectomy performed at the level suggested by the symptoms; operation is, however, rarely called for.

Intra-medullary Haemorrhage--Haematomyelia.--Traumatic haemorrhage into the substance of the cord occurs almost invariably in the lower cervical region, and results from forcible stretching of the cord by acute flexion of the neck. The blood is usually effused into the anterior cornua of the grey matter and into the central canal, and there is a varying degree of laceration of the nerve tissue, in addition to pressure exerted by the extravasated blood.

The severity of the clinical features depends upon the extent of the lesion. In contrast with what results in extra-medullary haemorrhage, the symptoms are paralytic from the outset.

When the haemorrhage is only sufficient to cause pressure on the cord, the paralysis is usually most marked in the lower extremities because the conducting fibres are pressed upon. This is associated with evanescent anaesthesia for temperature and pain, while tactile sensibility is preserved. There is retention of urine and faeces, and in young men, priapism. As the fibres which supply the dilator pupillae are involved, the pupils are contracted. The symptoms gradually subside as the extravasated blood is re-absorbed, sensation being restored before motion, and recovery may be comparatively rapid.

When the blood extravasated in the cord causes disintegration of its substance, there is complete paralysis with atrophy, and anaesthesia in the area supplied by the segments of the cord directly implicated. The paralysis in the parts below the lesion assumes the spastic form. As the lesion is usually in the upper part of the cord, it is the arms that are most frequently affected. In less severe degrees of damage the paralysis of the most distant parts, e.g. the feet, may be transitory. Even in cases in which the loss of function below the level of the lesion has been complete, recovery may take place, but it is apt to be marred by a spastic condition of the muscles concerned, due to sclerotic changes in the cord.

Except that operative treatment is contra-indicated, the treatment is the same as for extra-medullary haemorrhage, and at a later period measures may be employed to relieve the spastic condition of the muscles.

#Total Transverse Lesions.#--Total transverse lesions, that is, those in which the cord is completely crushed or torn across, are much more common than partial lesions, being an almost invariable accompaniment of a complete dislocation or of a fracture-dislocation of the spine. Even when the displacement of the vertebrae is only partial and temporary, the cord may be completely torn across. Similar lesions may result from stabs or bullet-wounds.

From the records of cases in which the vertebrae were injured by modern rifle bullets, even although the bony walls of the spinal canal had not been fractured and no haemorrhage had occurred within the spinal canal, the cord in the vicinity was degenerated into a "custard-like material" incapable of any conducting power (Makins). According to Stevenson, "this must have been due to the vibratory concussion communicated to it by the passage of the bullet at a high rate of velocity." The importance of this observation lies in the fact that in such cases no benefit can follow operative interference.

The clinical features vary with the level at which the cord is injured, and the diagnosis as to the nature and site of the lesion is to be made by a careful analysis of the symptoms. By gently passing the fingers under the patient's back as he lies recumbent, any irregularity in the spinous processes or laminae may be detected, but movement of the patient to admit of a more direct examination of the spine is attended with considerable risk, and should be avoided. Skiagrams are indispensable, as they show the exact site and nature of the lesion.

Immediate Symptoms.--At whatever level the cord is damaged there is immediate and complete paralysis of motion and sensation (paraplegia) below the seat of injury, and the paralysed limbs at once become flaccid. On careful examination, a narrow zone of hyperaesthesia may be mapped out above the anaesthetic area, and the patient may complain of radiating pain in the lines of the nerves derived from the segments of the cord directly implicated. In complete transverse lesions the paralytic symptoms are symmetrical; any marked difference on the two sides indicates an incomplete lesion.

Retention of urine and retention or incontinence of faeces are constant symptoms. In young men priapism is common--the corpus cavernosum penis is filled with blood without actual erection. There is other evidence of vaso-motor paralysis in the form of dilatation of the subcutaneous vessels, and local elevation of temperature in the paralysed parts. The deep reflexes, including the tendon reflexes, are permanently lost.

Unless regularly emptied by the catheter, the bladder becomes distended, and there is dribbling of urine--the overflow from the full bladder. As the bladder is unable to empty itself, and its trophic nerve supply is interfered with, the use of the catheter involves considerable risk of infection, unless the most rigid precautions are adopted. Hypostatic pneumonia is liable to develop. Great care in nursing is necessary to prevent trophic sores occurring over parts subjected to pressure, such as the sacrum, the scapulae, the heels, and the elbows.

Later symptoms are the result of descending degeneration taking place in the antero-lateral columns of the cord. There are often violent and painful jerkings of the muscles of the limbs; the muscles become rigid and the limbs flexed.

Treatment.--When the cord is completely divided, no benefit can follow operative interference, and treatment is directed towards the prevention of infective complications from cystitis and bed-sores.

#Injuries of the Cord at Different Levels.#--Cervical Region.--Complete lesions of the first four cervical segments--that is, above the level of the disc between the third and fourth cervical vertebrae--are always rapidly, if not instantaneously, fatal, as respiration is at once arrested by the destruction of the fibres which go to form the phrenic nerve. It is from this cause that death results in judicial hanging.

In lesions between the fifth cervical and first thoracic segments inclusive, all four limbs are paralysed. Sensation is lost below the second intercostal space. The parts above this level retain sensation, as they are supplied by the supra-clavicular nerves which are derived from the fourth cervical segment (Fig. 205). Recession of the eyeballs, narrowing of the palpebral fissures, and contraction of the pupils result from paralysis of the cervical sympathetic. Respiration is almost exclusively carried on by the diaphragm, and hiccup is often persistent. There is at first retention of urine, followed by dribbling from overflow, and sugar is sometimes found in the urine. Priapism is common. The pulse is slow (40 to 50) and full; and the temperature often rises very high--a symptom which is always of grave omen.

When the lesion is confined to the sixth cervical segment, the arms assume a characteristic attitude as a result of the contraction of the muscles supplied from the higher segments. The upper arm is abducted and rotated out, the elbow is sharply flexed, and the hand supinated and flexed (Fig. 206). Sensation is retained along the radial side of the limb.

Total lesions of the lower cervical segments are usually fatal in from two to three days to as many weeks, from embarrassment of respiration and hypostatic pneumonia.

When the lesion is confined to the first thoracic segment, the attitude of the arms is usually that of slight abduction at the shoulder and flexion at the elbow, the forearms lie semi-pronated on the chest or belly, and there is slight flexion of the fingers. There is complete anaesthesia as high as the level of the second interspace, and along the distribution of the ulnar nerve (Fig. 205); the respiration is entirely diaphragmatic; and the ocular changes depending on paralysis of the cervical sympathetic are present.

Thoracic Region.--In injuries of the thoracic region--second to eleventh thoracic segments inclusive--the anaesthesia below the level of the lesion is complete and its upper limit runs horizontally round the body, and not parallel with the intercostal nerves. Above the anaesthetic area there is a zone of hyperaesthesia, and the patient complains of a sensation as if a band were tightly tied round the body--"girdle-pain."

The motor paralysis and the anaesthesia are co-extensive. The intercostal muscles below the seat of the lesion and the abdominal muscles are paralysed. The respiratory movements are thus impeded, and, as the patient is unable to cough, mucus gathers in the air-passages and there is a tendency to broncho-pneumonia. As the patient is unable to aid defecation or to expel flatus by straining, the bowel is liable to become distended with faeces and gas, and the meteorism which results adds to the embarrassment of respiration by pressing on the diaphragm. There is retention of urine followed by dribbling from overflow. As the reflex arc is intact there may be involuntary and unconscious micturition whenever the bladder fills.

If infection of the bladder and the formation of bed-sores are prevented, the patient may live for months or even for years. At any time, however, infection of the bladder may occur and spread to the kidneys, setting up a pyelo-nephritis; or the patient may develop an ascending myelitis, and these conditions are the most common causes of death.

Lumbo-sacral Region.--All the spinal segments representing the lumbar, sacral, and coccygeal nerves lie between the level of the eleventh thoracic and first lumbar vertebrae. Injuries of the lower thoracic and upper lumbar vertebrae, therefore, may produce complete paralysis within the area of distribution of the lumbar and sacral plexuses. The anaesthesia reaches to about the level of the umbilicus. There is incontinence of urine and faeces from the first. Priapism is absent. Bed-sores and other trophic changes are common, and there is the usual risk of complications in relation to the urinary tract.

Conus Medullaris.--A lesion confined to the conus medullaris may result from a fall in the sitting position. It is attended with slight weakness of the legs, anaesthesia involving a saddle-shaped area over the buttocks and back of the thighs, the perineum, scrotum, and penis. The urethra and anal canal are insensitive, and there is paralysis of the levatores ani, the rectal and the vesical sphincters. The testes retain their sensation.

Cauda Equina.--As the cord terminates opposite the lower border of the first lumbar vertebra, injuries below this level implicate the cauda equina. The extent of the motor and sensory paralysis varies with the level of the lesion and with the particular nerves injured. Sometimes it is complete, sometimes, selective. As a rule all the muscles of the lower extremity are paralysed, except those supplied by the femoral (anterior crural), obturator, and superior gluteal nerves. The perineal and penile muscles are also implicated. There is anaesthesia of the penis, scrotum, perineum, lower half of the buttock, and the entire lower extremity, except the front and lateral aspects of the thigh, which are supplied by the lateral cutaneous nerve and the cutaneous branches of the femoral (anterior crural). There is incontinence of urine and faeces. The prognosis is more favourable than in lesions affecting the cord itself, and the only risk to life is the occurrence of infective complications.

#Partial Lesions of the Cord and Nerve Roots.#--Partial lesions, such as bruises, lacerations, or incomplete ruptures, are always attended with haemorrhage into the substance of the cord, and usually result from distortions or incomplete fractures and dislocations of the spine, or from bullet wounds. They are comparatively rare.

When the nerve roots alone are injured, sensory phenomena predominate. Formication, radiating pains, and neuralgia are present in the area of distribution of the nerves implicated. There is motor paresis or paralysis, which may disappear either suddenly or gradually, or may persist and be followed by atrophy of the muscles concerned. In contrast to what is observed from pressure by tumours and inflammatory products, twitchings and cramps are rare.

In partial lesions of the cord the motor phenomena predominate. Paresis extends to the whole of the motor area below the seat of the lesion, but the weakness is more marked on one side of the body. The distal parts--feet and legs--suffer more than the proximal--arms and hands, and the extensors more than the flexors. The paresis develops slowly, varies in extent and degree, and may soon improve. Vaso-motor disturbances accompany the motor symptoms. Irritative phenomena, such as twitchings or contractures, may come on later.

The deep reflexes, particularly the knee-jerks, may be absent at first, but they soon return, and are usually exaggerated; a well-marked Babinski response may appear later. Abolition of the reflexes, therefore, does not necessarily indicate complete destruction of the cord, but their return is conclusive evidence that the lesion is a partial one. It is necessary, therefore, to defer judgment until it is determined whether the abolition of the reflexes is temporary or permanent.

Sensory disturbances may be entirely absent. When present, they are incomplete, and are chiefly irritative in character. They may not reach the same level as the motor phenomena, and the different sensory functions are unequally disturbed in the areas corresponding to the several nerve roots. There is sometimes a combination of hyperaesthesia on one side and anaesthesia on the other.

Retention of urine is not always present even in those cases in which the limbs are completely paralysed, as the fibres of one side of the cord are sufficient to maintain the functions of the bladder. The patient may be aware that the bladder is full, although he is unable to empty it. Similarly, sensation in the rectum and anus may be retained although the control of the sphincters is lost. Priapism may be present, but tends to disappear.

In partial lesions, the difficulties of diagnosis are sometimes increased by the occurrence of haemorrhage into the substance of the cord, so that symptoms of generalised pressure are superadded to those of the partial lesion. In time the symptoms due to the intra-medullary haemorrhage pass off, but those due to the tearing of the cord persist.

The prognosis is generally favourable, but must be guarded, as permanent organic changes in the cord may take place, causing a spastic condition of the muscles. When recovery is taking place the first signs are the return of the knee-jerks, and a gradual change in the limbs from the flaccid to the spastic condition. Sensibility returns in the order--touch, pain, temperature, and the parts supplied by the lowest sacral segments usually become sentient first. Voluntary power returns earlier in the flexors than in the extensors, and flexion of the toes is almost invariably the earliest voluntary movement possible. Infection from bed-sores or from the urinary tract is the most common cause of death in cases that terminate fatally.

The treatment is carried out on the same lines as for total lesions. Laminectomy, however, is indicated when there is reason to believe that the pressure is due to some cause, such as a blood-clot or a displaced fragment of bone, which is capable of being removed.

In practice when a person has lost the power of the lower extremities as the result of an accident, there are three conditions requiring ultimate differentiation--a concussion of the cord alone, a total transverse lesion and a partial lesion of the cord together with concussion. It must again be emphasised that it may not be possible to differentiate between these immediately after the accident. Two or three days may elapse before it is possible to give a definite opinion.

"#Railway Spine.#"--This term is employed to indicate a disturbance of the nervous system which may develop in persons who have been in railway accidents, but a similar group of symptoms is met with in men engaged in laborious occupations such as coal-miners, who, after an injury to the back, develop symptoms referable to the nervous system on account of which they claim compensation not infrequently in the law-courts. It is a remarkable fact that it seldom occurs in railway employees, or in passengers who sustain gross injuries, such as fractures or lacerated wounds.

Clinical Features.--The patient usually gives a history of having been forcibly thrown backwards and forwards across the carriage at the time of the accident. He is dazed for a moment and suffers from shock or, it may be, is little the worse at the time, and is able to continue his journey. On reaching his destination, however, he feels weak and nervous, and complains of pain in his back and limbs. There is rarely any sign of local injury. For a few days he may be able to attend to business, but eventually feels unfit, and has to give it up.

The symptoms that subsequently develop are for the most part subjective, and it is difficult therefore either to corroborate or to refute them; it will be observed that while some of them are referable to the cord the greater number are referable to the brain. They usually include a feeling of general weakness, nervousness, and inability to concentrate the attention on work or on business matters. The patient is sleepless, or his sleep is disturbed by terrifying dreams. His memory is defective, or rather selective, as he can usually recall the circumstances of the accident with clearness and accuracy. He becomes irritable and emotional, complains of sensations of weight or fullness in the head, of temporary giddiness, is hypersensitive to sounds, and sometimes complains of noises in the ears. There are weakness of vision and photophobia, but there are no ophthalmoscopic changes. He has pain in the back on making any movement, and there is a diffuse tenderness or hyperaesthesia along the spine. There is weakness of the limbs, sometimes attended with numbness, and he is easily fatigued by walking. There may be loss of sexual power and irritability of the bladder, but there is seldom any difficulty in passing urine. The patient tends to lose weight, and may acquire an anxious, careworn expression, and appear prematurely aged. Special attention should be directed to the condition of the deep reflexes and to the state of the muscles, as any alteration in the reflexes or atrophy of the muscles indicates that some definite organic lesion is present.

As the symptoms are so entirely subjective, it is often extremely difficult to exclude the possibility of malingering; it is essential that the patient should be examined with scrupulous accuracy at regular intervals and careful notes made for purposes of comparison, and also that the doctor should retain an impartial attitude and not develop a bias either in favour of or against the patient's claim for compensation.

So long as litigation is pending the patient derives little benefit from treatment, but after his mind is relieved by the settlement of his claim--whether favourable to him or not--his health is usually restored by the general tonic treatment employed for neurasthenia.

INJURIES OF THE VERTEBRAL COLUMN

Partial lesions include twists or sprains, isolated dislocations of articular processes, isolated fractures of the arches and spinous processes, and isolated fractures of the vertebral bodies. The most important complete lesions are total dislocations and fracture-dislocations.

In partial lesions, the continuity of the column as a whole is not broken, and the cord sustains little damage, or may entirely escape; in complete lesions, on the other hand, the column is broken and the cord is always severely, and often irreparably, damaged.

Twists and dislocations are most common in the cervical region, that is, in the part of the spine where the forward range of movement--flexion--is greatest. Fractures are most common in the lumbar region, where flexion is most restricted. Fracture-dislocations usually occur where the range of flexion is intermediate, that is, in the thoracic region.

In all lesions accompanied by displacement, the upper segment of the spine is displaced forwards.

#Twists# or #sprains# are produced by movements that suddenly put the ligamentous and muscular structures of the spine on the stretch--in other words, by lesser degrees of the same forms of violence as produce dislocation. When the interspinous and muscular attachments alone are torn, the effects are confined to the site of these structures, but when the ligamenta flava are involved, blood may be extravasated and infiltrate the space between the dura and the bone and give rise to symptoms of pressure on the cord. The nerve roots emerging in relation to the affected vertebrae may be stretched or lacerated, and as a result radiating pains may be felt in the area of their distribution.

In the cervical region, distortion usually results either from forcible extension of the neck--for example from a violent blow or fall on the forehead forcing the head backwards--or from forcible flexion of the neck. The patient complains of severe pain in the neck, and inability to move the head, which is often rigidly held in the position of wry-neck. There is marked tenderness on attempting to carry out passive movements, and on making pressure over the affected vertebrae or on the top of the head. The maximum point of tenderness indicates the vertebra most implicated. In diagnosis, fracture and dislocation are excluded by the absence of any alteration in the relative positions of the bony points, and by the fact that passive movements, although painful, are possible in all directions.

In the lumbar region sprains are usually due to over-exertion in lifting heavy weights, or to the patient having been suddenly thrown backwards and forwards in a railway collision. The attachments of the muscles of the loins are probably the parts most affected. The back is kept rigid, and there is pain on movement, particularly on rising from the stooping posture.

Treatment.--Unless carefully treated, a sprain of the spine is liable to cause prolonged disablement. The patient should be kept at rest in bed, and, when the injury is in the cervical region, extension should be applied to the head with the nape of the neck supported on a roller-pillow. Early recourse should be had to massage, but active movements are forbidden till all acute symptoms have disappeared. In patients predisposed to tuberculosis, the period of complete rest should be materially prolonged.

#Isolated Dislocation of Articular Processes.#--This injury, which is most frequently met with in the cervical region and is nearly always unilateral, is commonly produced by the patient falling from a vehicle which suddenly starts, and landing on the head or shoulders in such a way that the neck is forcibly flexed and twisted. The articular process of the upper vertebra passes forward, so that it comes to lie in front of the one below.

The pain and tenderness are much less marked than in a simple twist, as the ligaments are completely torn and are therefore not in a state of tension. The patient often thinks lightly of the condition at the time of the accident, and may only apply for advice some time after on account of the deformity. The head is flexed and the face turned towards the side opposite the dislocation, the attitude closely resembling that of ordinary wry-neck, only it is the opposite sterno-mastoid that is tight. The bony displacement is best recognised by palpating the transverse process of the dislocated vertebra. In the case of the upper vertebrae this is done from the pharynx, in the lower between the sterno-mastoid and the trachea. There is pain on attempting movement, and tenderness on pressure, particularly on the side that is not displaced, as the ligaments there are on the stretch. There are often radiating pains along the line of the nerves emerging between the affected vertebrae. As the bodies are not separated, damage to the cord is exceptional. The lesion can usually be recognised in a radiogram.

Treatment.--Reduction should be attempted at once, before the vertebrae become fixed in their abnormal position. Under anaesthesia gentle extension is made on the head by an assistant, and the abnormal attitude is first slightly exaggerated to relax the ligaments and to restore mobility to the locked articular processes. The head is then forcibly flexed towards the opposite side, after which it can be rotated into its normal attitude (Kocher). Haphazard movements to effect reduction are attended with risk of damaging the cord. After reduction has been effected, the treatment is the same as that of a sprain.

#Isolated Fractures of the Arches, Spinous and Transverse Processes.#--Fractures of the arches and spinous processes usually result from direct violence, such as a blow or a bullet wound, and are accompanied by bruising of the overlying soft parts, irregularity in the line of the spines, and by the ordinary signs of fracture. Skiagrams are useful in showing the exact nature of the lesion. These fractures are most common in the lower cervical and in the thoracic regions, where the spines are most prominent and therefore most exposed to injury.

In many cases there are no symptoms of damage to the cord or spinal nerves, but when both laminae give way the posterior part of the arch may be driven in and cause direct pressure on the cord, or blood may be effused between the bone and the dura. In such cases immediate operation is indicated. When there are no cord symptoms, the treatment consists in securing rest, with the aid of extension, if necessary, for several weeks until the bones are reunited.

The use of the X-rays has shown that one or more of the transverse processes of the lumbar vertebrae may be chipped off by direct violence. The symptoms are pain and tenderness in the region of the fracture, and marked restriction of movement, especially in the direction of flexion. This lesion may explain some of the cases of persistent pain in the back following injuries in workmen. It is important to remember, however, that in a radiogram an un-united epiphysis may simulate a fracture.

#Isolated Fracture of the Bodies--"Compression Fracture."#--The "compression fracture" consists in a crushing from above downwards of the bodies--and the bodies only--of one or more vertebrae. It is due to the patient falling from a height and landing on the head, buttocks, or feet in such a way that the force is transmitted along the bodies of the vertebrae while the spine is flexed.

If the patient lands on his head, the compression fracture usually involves the lower cervical or upper thoracic vertebrae. When he lands on his buttocks or feet it is usually the lumbar or the lower thoracic vertebrae that are fractured (Fig. 207).

As a rule, there are no external signs of injury over the spine. The sternum, however, is often fractured, and irregularity and discoloration may be detected on examining the front of the chest. The recognition of a fracture of the sternum should always raise the suspicion of a fracture of the spine. On examination of the back a more or less marked projection of the spinous processes of the damaged vertebrae may be recognised. In the cervical and lumbar regions this projection may merely obliterate the normal concavity. The spinous process which forms the apex of the projection belongs to the vertebra above the one that is crushed. The cord usually escapes, but the nerves emerging in relation to the damaged vertebrae may be bruised, and this gives rise to girdle-pain.

Local tenderness is elicited on pressing over the affected vertebrae. As might be expected from the nature of the accident producing this lesion, it is often associated with serious injuries to the head, limbs, or internal organs which gravely affect the prognosis.

The treatment consists in taking the pressure off the injured vertebrae in order that the reparative material may be laid down in such a way as to restore the integrity of the column. In the cervical region, extension is applied to the head, and a roller-pillow placed beneath the neck. In the lumbar region, the extension is applied through the lower limbs, and the pillow placed under the loins. The patient is confined to bed for six or eight weeks, and before he gets up a poroplastic or plaster-of-Paris jacket is applied. This is worn for a month or six weeks.

#Traumatic Spondylitis.#--This condition is liable to develop in patients who have sustained a severe injury to the back. It is believed to originate in a compression fracture which has not been recognised, and is probably due to the callus thrown out for the repair of the fracture being subjected to strain and pressure too early, or to a progressive softening of the injured vertebra and of the bodies of those adjacent to it. This leads to an alteration in the shape of the affected bones, which can be demonstrated by means of the X-rays. The usual history is that some considerable time after the patient has resumed work he suffers from pain in the back, and radiating pains round the body and down the legs. He becomes more and more unfit for work, and a marked projection appears in the back and may come to involve several vertebrae. While the condition is progressive, the prominent vertebrae are painful and tender. In course of time the softening process is arrested, and the affected bones become fused, so that the area of the spine involved becomes rigid and permanent deformity results. So long as the condition is progressive the patient should be kept in the recumbent and hyper-extended position over a roller-pillow and, when he gets up, the spine should be supported by a jacket.

#Dislocation and Fracture-Dislocation.#--It is seldom possible at the bedside to distinguish between a complete dislocation of the spine and a fracture-dislocation. Fracture-dislocation is by far the more common lesion of the two, and is the injury popularly known as a "broken back." It may occur in any part of the column, but is most frequently met with in the thoracic and thoracico-lumbar regions. It usually results from forcible flexion of the spine, as, for example, when a miner at work in the stooping posture is struck on the shoulders by a heavy fall of coal. The spine is acutely bent, and breaks at the angle of flexion and not at the point struck. The lesion consists in a complete bilateral dislocation of the articular processes, together with a fracture through one or more of the bodies. This fracture is usually oblique, running downwards and forwards. The upper fragment with the segment of the spine above it is displaced downwards and forwards, and the cord is crushed between the posterior edge of the broken body and the arch of the vertebra above it (Fig. 208). In almost every case the cord is damaged beyond repair.

Total dislocation, in which the articular processes on both sides are displaced and the contiguous intervertebral disc separated, is rare, and is met with chiefly in the lower cervical region.

Clinical Features.--The outstanding symptoms of total lesions are referable to the damage inflicted on the cord. The diagnosis should always be made by a consideration of the mechanism of the injury and the condition of the nerve functions below the lesion. On no account should the patient be moved to enable the back to be examined, as this is attended with risk of increasing the displacement and causing further damage to the cord. On passing the fingers under the back as the patient lies recumbent, it is usually found that there is some backward projection of the spinous processes, the most prominent being that of the broken vertebra. The spinous process immediately above it is depressed as the upper segment has slipped forward. Pain, tenderness, swelling and discoloration may be present over the injured vertebrae. It is usually possible to have skiagrams taken without risk of further damage to the spine. There is complete loss of motion and sensation below the seat of the lesion. The symptoms of total transverse lesions of the cord at different levels have already been described (p. 416).

Treatment.--An attempt may be made to reduce the displacement under anaesthesia, gentle traction being made in the long axis of the spine by assistants, while the surgeon attempts to mould the bones into position. No special manipulations are necessary, as the ligaments are extensively torn, and the bones are, as a rule, readily replaced. A roller-pillow is placed under the seat of fracture to allow the weight of the body above and below to exert gentle traction, and so to relieve pressure on the cord. Operative treatment is almost never of any avail, as the cord is not merely pressed upon, but is severely crushed, or even completely torn across. Even when the cord is only partially torn, operative treatment is not likely to yield better results than are obtained by reduction and extension. The usual precautions must be taken to prevent cystitis and bed-sores.

Total fracture-dislocation between the atlas and epistropheus (axis), if attended with displacement, is instantaneously fatal (Fig. 209). This is the osseous lesion that occurs in judicial hanging. Fracture of the odontoid process may occur, however, without displacement, the transverse ligament retaining the fragment in position and protecting the cord from injury. The patient complains of stiff neck and pain, and the lesion may be recognised in a radiogram. A number of cases are recorded in which death took place suddenly weeks or months after such an injury, from softening of the transverse ligament and displacement of the bones.

#Penetrating Wounds.#--These result from stabs or gun-shot accidents, and are practically equivalent to compound fractures of the spine; their severity depends on the extent of the damage done to the cord, and on whether or not the wound is infected. In many cases the condition is complicated by injuries of the pleural or peritoneal cavities and their contained viscera, or by injury of the trachea, oesophagus, or large vessels and nerves of the neck. When the membranes of the cord are opened, the profuse and continued escape of cerebro-spinal fluid may prove a serious complication.

Treatment.--The wound of the soft parts is treated on the usual lines. When the spinous processes and laminae are driven in upon the cord, they must be elevated at once by operation. In injuries involving the lumbo-sacral region it is sometimes advisable to perform laminectomy for the purpose of suturing divided nerve cords.

When there is evidence that the spinal cord is completely divided, operation is contra-indicated. Attempts have been made to unite the two ends of the divided cord by sutures, but there is as yet no authentic record of restoration of function following the operation.

XVII. DISEASES OF THE VERTEBRAL COLUMN AND SPINAL CORD

POTT'S DISEASE: Pathology; Clinical features--Pott's disease as it affects different regions of the spine--Disease of the sacro-iliac joint; Syphilitic disease of spine; Tumours of vertebrae; Hysterical spine; Acute osteomyelitis; Rheumatic spondylitis; Arthritis deformans; Coccydynia; Tumours of cord and membranes--Spinal meningitis; Spinal myelitis--Congenital deformities: Spina bifida; Congenital sacro-coccygeal tumours. Congenital sacro-coccygeal sinuses and fistulae.

TUBERCULOUS DISEASE OF THE SPINE--POTT'S DISEASE

Percival Pott, in 1779, first described a disease of the vertebral column which is characterised by erosion and destruction of the bodies of the vertebrae. It is liable to produce an angular deformity of the spine, and to be associated with abscess formation and with nervous symptoms referable to pressure on the cord. This disease is now known to be tuberculous. It may occur at any period of life, but in at least 50 per cent. of cases it attacks children below the age of ten and rarely commences after middle life.

#Morbid Anatomy.#--The tuberculous process may affect any portion of the spine, and as a rule is limited to one region; several vertebrae are usually simultaneously involved. The disease may begin either in the interior of the bodies of the vertebrae--tuberculous osteomyelitis--or in the deeper layer of the periosteum on the anterior surface of the bones--tuberculous periostitis.

Osteomyelitis is the form most frequently met with in children. The disease commences as a tuberculous infiltration of the marrow, which results in softening of the bodies of the affected vertebrae, particularly in their anterior parts, and, as the disease progresses, caseation and suppuration ensue, and the destructive process spreads to the adjacent intervertebral discs. In some cases a sequestrum is formed, either on the surface or in the interior of a vertebra. The pus usually works its way towards the front and sides of the bones, and burrows under the anterior longitudinal (common) ligament. Less frequently it spreads towards the vertebral canal and accumulates around the dura, causing pressure on the cord.

The compression of the diseased vertebrae by the weight of the head and trunk above the seat of the lesion, and by the traction of the muscles passing over it, produces angling of the vertebral column. The anterior portions of the bodies being more extensively destroyed, sink in, while the less damaged posterior portions and the intact articular processes prevent complete dislocation. In this way the integrity of the canal is maintained, and the cord usually escapes being pressed upon. The spinous processes of the affected vertebrae project and form a prominence in the middle line of the back. When, as is usually the case, only two or three vertebrae are implicated, this prominence takes the form of a sharp angular projection, while if a series of vertebrae are involved, the deformity is of the nature of a gentle backward curve (Fig. 210).

The periosteal form of vertebral tuberculosis is that most frequently met with in adults. The disease begins in the deeper layer of the periosteum on the anterior aspect of the vertebrae, and extends along the surface of the bones, causing widespread superficial caries. It may attack the discs at their margins, and spread inwards between the discs and the contiguous vertebrae. Owing to the comparatively wide area of the spine implicated, this form of the disease is not attended with angular deformity, but rather with a wide backward curvature which corresponds in extent to the number of vertebrae affected. The accumulation of tuberculous pus under the periosteum and anterior longitudinal ligament is the first stage in the formation of the large abscesses with which this form of spinal tuberculosis is so commonly associated.

Effects on the Spinal Cord and Nerve Roots.--In some cases the cord and nerve roots are pressed upon by an oedematous swelling of the membranes; in others, the tuberculous process attacks the dura mater and gives rise to the formation of granulation tissue on its outer aspect--tuberculous pachymeningitis. Less frequently a collection of pus forms between the bone and the dura, and presses the cord back against the laminae. The cord is rarely subjected to pressure as a result of curving of the spine alone, but occasionally, especially in the cervical region, a sequestrum becomes displaced backward and exerts pressure on it, and it sometimes happens, also in the cervical region, that the cord is nipped by sudden displacement of diseased vertebrae--a condition comparable to a fracture-dislocation of the spine.

The severity of the symptoms is aggravated by the occurrence of inflammation of the cord--myelitis--which is not due to tuberculous disease, but to interference with its blood-supply from the associated meningitis.

Repair.--When the progress of the disease is arrested, the natural cure of the condition is brought about by the bodies of the affected vertebrae becoming fused by osseous ankylosis (Fig. 211). While this reparative process is progressing, the cicatricial contraction renders the angular deformity more acute, and it may go on increasing until the bones are completely ankylosed; this reparative process can be followed in successive skiagrams. An increase in the projection in the back, therefore, is not necessarily an unfavourable symptom, although, of course, it is undesirable.

In rare cases the disease affects only the articular or the spinous processes, producing superficial caries and a localised abscess.

#Clinical Features.#--The clinical features of Pott's disease vary so widely in different regions of the spine, that it is necessary to consider each region separately. To avoid repetition, however, certain general features may be first described.

Pain.--In the earliest stages, the patient complains of a feeling of tiredness, which prevents him walking far or standing for any length of time. Later, there is a constant, dull, gnawing pain in the back, increased by any form of movement, particularly such as involves jarring or bending of the spine. If the patient is a child, it is noticed that he ceases to play with his companions, and inclines to sit or lie about, usually assuming some attitude which tends to take the weight off the affected segment of the spine (Figs. 214, 217). If he is going about, the pain increases as the day goes on, but may pass off during the night. It is often referred along the course of the nerves emerging between the diseased vertebrae, and takes the form of headache, neuralgic pains in the arms or side, girdle-pain, or belly-ache, according to the seat of the lesion. Tenderness may be elicited on pressing over the spinous or transverse processes of the diseased vertebrae, or on making pressure in the long axis of the spine. These tests, however, are not of great diagnostic value, and they should be omitted, as they cause unnecessary suffering. It is to be borne in mind that in some cases the disease is not attended with any pain.

Rigidity.--The pain produced by movement of the diseased portion of the spine causes reflex contraction of the muscles passing over it, and the affected segment of the column is thus rendered rigid. If the palm of the hand is placed over the painful area while the patient attempts to make movements of stooping, nodding, or turning to the side, it is found that the vertebrae implicated move en bloc instead of gliding on one another. This rigidity of the diseased portion of the column with "boarding" of the muscles of the back is one of the earliest and most valuable diagnostic signs of Pott's disease.

Deformity.--The most common and characteristic deformity is an abnormal antero-posterior curvature, with its convexity backwards. The situation, extent, and acuteness of the bend vary with the region of the spine affected, the situation of the disease in the bone, and the number of vertebrae implicated. When the disease has destroyed the bodies of one or two vertebrae, a short, sharp, angular deformity results; when it affects the surface of several bones, a long, wide curvature.

Lateral deviation is occasionally met with in the early stages of the disease as a result of unequal muscular contraction, and in the later stages from excessive destruction of one side of a vertebra, or from partial luxation between two diseased vertebrae.

Abscess Formation.--Spinal abscesses occur with greater frequency and at an earlier stage in adults than in children, because in adults the disease usually begins on the surface of the vertebrae. Pyogenic infection of such abscesses after they have burst externally constitutes one of the chief risks to life in Pott's disease.

X-Ray Appearances.--These, when considered along with the clinical signs, usually afford valuable information as to the exact seat and nature of the lesion and the number of vertebrae involved. It is recommended to compare the skiagram with that of the normal spine from the same region and from a patient of approximately similar age. The outlines of the bodies are woolly or blurred; in the early stage there may be clear areas corresponding to cheesy foci. In progressive cases the bodies may be altered in shape and in size, and from destruction and collapse of the bones there is altered spacing, both of the bodies and of the ribs. In the interpretation of skiagrams, help is often obtained from an alteration in the axis of bodies, an angular deviation often drawing attention to the lesion which is located at the "angle." In children (Fig. 213) there is often a spindle-shaped shadow, outlined against the vertebral column, which is due to a cold abscess, and which extends above and below the bodies actually involved in the tuberculous process. The fusion of the bodies by new bone, which accompanies repair, can be followed in skiagrams taken at intervals.

Cord and Nerve Symptoms.--When the spinal cord is pressed upon, the motor fibres are first affected as they lie superficially on the antero-lateral aspects of the cord, and are more sensitive to pressure. There is at first weakness or paresis of the muscles supplied from the part of the cord below the seat of pressure. The knee-jerks and plantar reflexes are exaggerated, and there is marked ankle clonus. Later, there is paralysis of the spastic type, varying in extent and sometimes amounting to complete paraplegia, and this may come on gradually or quite suddenly. There is wasting of muscles from disuse, and later a tendency to contracture and the development of deformities, as a result of sclerosis or descending degeneration of the cord.

The sensory fibres usually escape, although in some cases there is partial anaesthesia and perversion of sensation. When there is also myelitis, loss of sensibility to pain (analgesia) below the level of the lesion is one of the most characteristic symptoms. In severe cases there is incontinence of urine and of faeces, as the patient loses control of the sphincters. Acute bed-sores are not uncommon.

The symptoms referable to pressure on the nerve roots at their points of emergence are pain and hyperaesthesia along the course of the nerves that are pressed upon, and occasionally weakness and wasting of the muscles supplied by them; girdle-pain is often a prominent symptom in adults.

In the #diagnosis# of Pott's disease in young children, chief stress is laid on the demonstration of rigidity of the affected portion of spine; the child is laid prone and is lifted by the legs and feet so as to hyper-extend the spine; in Pott's disease the spine is held rigid, while in the rickety and other conditions that resemble it, the movements are normal.

#Treatment of Pott's Disease.#--In addition to the general treatment of tuberculosis, the essential factor consists in immobilising the spine in the recumbent posture and in the attitude of hyper-extension; this must be persisted in until the diseased vertebrae become fused together or ankylosed by new bone, a result which is estimated partly by the disappearance of all symptoms and more accurately by observing the formation of the new bone in successive skiagrams.

Under conservative measures it is estimated that this reparative process entails an immobilisation of the spine of from one to three years; the operative procedures introduced by Albe and Hibbs bring about a bony ankylosis of the vertebrae in as many months, and may be accepted as reducing the period of spinal immobilisation in the recumbent posture to one year at the most.

The immobilisation of the recumbent spine in the attitude of hyper-extension is most efficiently carried out by an apparatus on the lines of the Bradford frame; this is made of gas-piping covered by canvas, and is easily bent as may be required in the progress of the case towards convalescence. The frame does not interfere with such extension as may be necessary, to the head, for example, in recent cervical caries, or to the lower extremities where flexion at the hip from spasmodic contraction of the psoas muscle may be efficiently relieved by weight-extension.

Gauvain's "wheel-barrow" splint and the double Thomas' splint (Fig. 215) are efficient substitutes, but Phelps' box has been discarded because it fails to secure immobilisation of the spine.

When the stage of convalescence is arrived at, and recumbency is no longer essential, the child is allowed to sit up, stand, and go about, with the restraint, however, of some apparatus that will prevent movement of the spine, except to a limited extent. The plaster-of-Paris jacket, applied over a woollen jersey, as introduced by Sayre of New York, is probably the best; the jacket is accurately moulded to the trunk while the child is partly suspended by means of a tripod and the necessary strings under the chin, occiput, and armpits. Poroplastic felt, celluloid, papier mache, and other materials, reinforced by strips of metal, may be substituted for the plaster of Paris. Various forms of jury-masts and collars have been employed to diminish the weight of the head in children with cervical caries, but have been very properly discarded as failing to perform the function expected of them.

Correction of the Angular Projection.--In cases in which the angular projection or gibbus, as it is called by continental authors, is of recent origin, it may be corrected by the method so successfully employed by Calot of Berck-sur-Mer--a plaster jacket is accurately moulded to the trunk, and a diamond-shaped window is cut in the jacket opposite the gibbus; a series of layers of cotton-wool are then applied, one on top of the other, so as to exert firm pressure on the gibbus, a plaster or elastic webbing bandage being employed to retain them and reinforce the pressure. The padding is renewed at intervals of three weeks or a month; in successful cases the projection may ultimately be replaced by a hollow.

Treatment of Abscess.--If a spinal abscess is causing symptoms or is approaching the surface, and there appears to be a risk of mixed infection, the abscess should be asperated and injected with iodoform emulsion.

Treatment of Cord-Complications.--Extension is applied, in the first instance, to the head or to the lower limbs, or to both, while some form of pillow is inserted at the seat of the disease; if the condition is merely one of oedema, the symptoms usually yield with remarkable rapidity; if they persist, in spite of extension, for three to six weeks, recourse should be had to laminectomy; it is usual to find evidence of mechanical pressure by granulation tissue, pus, or displaced bone, the relieving of which is followed by disappearance of the nerve symptoms. Some authors are lukewarm in their advocacy of this operation, but we can cite a number of cases in which, after laminectomy, an apparently hopeless paraplegia has been entirely got rid of.

#Prognosis.#--As regards the survival of persons who have suffered from Pott's disease, and as having an important bearing on prognosis, it may be noted that surgical museums contain many specimens illustrating the "cured" stage of the disease, in which the bodies of the vertebrae, formerly the seat of tuberculous destruction or caries, are represented by a ridge-shaped mass of new bone, forming a solid union between the segments above and below (Fig. 211), or the remains of the original bodies may still be identifiable, although they are surrounded and fused together by new bone. The latter condition is the more liable to a recrudescence of the tuberculous infection. Further, it may be inferred from the number of "cured" cases of Pott's disease met with in everyday life, that the malady is one from which recovery may be expected.

The cervical cases are recognised by the "telescoping" of the neck, the head and thorax being unduly approximated; the dorsal cases by the well-known hump or hunch-back, in which the spinous processes of the collapsed vertebrae constitute the apex of the hump; the thorax is telescoped from above downwards, the ribs are crowded together, the lower ones, it may be, inside the iliac crests, and the sternum projected forwards. The hunch-back from Pott's disease is often a remarkably capable person, both physically and intellectually.

POTT'S DISEASE AS IT AFFECTS DIFFERENT REGIONS OF THE SPINE

#Upper Cervical Region, including Atlo-axoid Disease.#--When the disease affects the first and second cervical vertebrae, the atlo-axoid articulation becomes involved, and as a result of the destruction of its component bones and ligaments, the atlas tends to be dislocated forward. When this occurs suddenly, the odontoid process may impinge on the medulla and upper part of the cord and cause sudden death. When the displacement occurs gradually, the atlas and axis may be separated to a considerable extent without the cord being pressed upon, and recovery with ankylosis may ensue. When the third, fourth, and fifth vertebrae are affected, the tendency to dislocation and compression of the cord is not so great, but a portion of bone may be displaced backwards and exert pressure on the cord.

The patient complains of a fixed pain in the back of the neck, and of radiating pains along the course of the sub-occipital and other cervical nerves. The neck is held rigid, and to look to the side the patient turns his whole body round. As the disease advances the head may be bent to one side as in wry-neck, or it may be retracted and the chin protruded. To take the weight of the head off the diseased vertebrae the patient often supports the chin on the hands (Fig. 214).

An abscess may form between the vertebrae and the wall of the pharynx--retro-pharyngeal abscess--the pus accumulating between the diseased bones and the prevertebral layer of the cervical fascia. The abscess may project towards the pharynx as a soft fluctuating swelling, and may cause difficulty in swallowing and breathing, and snoring during sleep; if it bursts internally it may cause suffocation. The abscess may bulge towards one or both sides of the neck, and come to the surface behind the posterior border of the sterno-mastoid muscle (Fig. 214). In some cases it comes to the surface in the sub-occipital region.

If the cord is pressed upon by inflammatory products, there is muscular weakness, beginning in the arms and extending to the legs, and sometimes followed by complete paralysis. In the early stages there is retention of urine and constipation; later the bladder and rectum are paralysed, and there is incontinence.

Sudden death may result when dislocation of the atlo-axoid joint takes place.

Cervical caries has to be diagnosed from rheumatic torticollis, and from the effects of injuries, such as a sprain or twist of the spine. When a retro-pharyngeal abscess points behind the sterno-mastoid, it is apt to be mistaken for a cold abscess originating in tuberculous cervical glands. Retro-pharyngeal abscess due to other causes is described with diseases of the pharynx.

Treatment.--Extension is applied to the head, preferably by means of an elastic band fixed to the top of the bed, and the head of the bed is raised on blocks so that the weight of the body may furnish the necessary counter-extension. Lateral movements of the head are prevented by means of sand-bags. After the acute symptoms have subsided, the spine should be fixed by some rigid apparatus, such as a double Thomas' splint prolonged so as to support the occiput (Fig. 215).

When it is considered advisable to open a retro-pharyngeal abscess, this should be done from the side of the neck by an incision along the posterior border of the sterno-mastoid, as first recommended by John Chiene. The abscess is evacuated, and the cavity filled with iodoform emulsion, and closed without drainage. An opening made through the mouth is attended with the risks of pus being inhaled into the air-passages and of pyogenic infection.

When the patient is allowed to get up, a poroplastic collar and jacket of the Minerva type which supports the head and controls the movement of the cervical and thoracic vertebrae must be worn until the cure is complete.

#Cervico-thoracic Region.#--When the lower cervical and upper thoracic vertebrae are affected, in addition to the fixed pain in the diseased bones, the patient complains of pain radiating along the distribution of the superficial cervical nerves and down the arms. There is often marked angular deformity. If an abscess forms, it may come to the surface in the lower part of the posterior triangle, or may spread into the posterior mediastinum or into the axilla. Sometimes the pus burrows behind the oesophagus and trachea, and it may find its way into the pleural cavity. The cord is not often pressed upon; when it is, the cervical sympathetic is implicated.

#Thoracic or Dorsal Region.#--When the disease is confined to the thoracic region, stiffness of the back and boarding of the vertebral muscles are prominent features. On being asked to pick up an object from the floor, the patient reaches it by bending his knees and hips, while he keeps his back rigid. He refuses to make any movement that involves jolting of the spine, such, for example, as jumping from a chair to the ground. Children often attempt to take the weight off the diseased vertebrae by placing the palms of the hands on the edge of a chair so that the weight is borne by the arms.

Angular deformity is often well marked, and may implicate several vertebrae. In order to maintain the head erect, the spine above and below the seat of disease becomes unduly arched forward--compensatory lordosis. In advanced cases the ribs become approximated, and the lower end of the sternum is projected forward. The antero-posterior diameter of the thorax is thus increased, while its vertical diameter is diminished. These changes, together with the telescoping of the vertebral bodies, lead to the deformity characteristic of the tuberculous hunch-back (Fig 216). The alterations in the shape of the chest may lead to functional disturbances of the heart and lungs.

Dorsal Abscess.--As already mentioned, the earliest stage of abscess is well seen in skiagrams (Fig. 213), especially in children. When there is an extension of the suppurative process, the pus may pass directly backwards along the posterior branches of the intercostal vessels and nerves, and come to the surface behind the transverse processes, or it may travel forward between the pleura and the ribs, and, passing along the course of the lateral cutaneous branches of the intercostals, come to the surface opposite the middle of the rib. In the latter case, the abscess is liable to be mistaken for one associated with tuberculous disease of the rib, particularly as the rib is usually found to be bare. In rare cases the pus opens into the pleura, giving rise to empyema. When the disease is on the anterior surface of the bodies of the lower thoracic vertebrae, the pus may spread down through the pillars of the diaphragm and reach the sheath of the psoas muscle.

Treatment is on the usual lines.

#Thoracico-lumbar Region.#--The symptoms are similar to those of disease in the thoracic region. Children while standing often assume a characteristic attitude--the hips and knees are slightly flexed, and the hands grasp the thighs just above the knees (Fig. 217). In this way the weight is partly taken off the affected vertebrae and borne by the arms. If the child is laid on its back and lifted by the heels, the spine remains rigid. By this test a projection due to tuberculous disease may be differentiated from one due to rickets, as in the latter case the projection disappears.

The patient often complains of pain in the abdomen--which in children may be mistaken for a simple "belly-ache"--and of pain shooting down the buttocks and into the legs. If the cord is pressed upon at the level of the lumbar enlargement the anal and vesical sphincters are paralysed, and the reflexes are exaggerated.

Psoas Abscess.--When an abscess forms, it usually occupies the sheath of the psoas muscle, in which it spreads down towards the iliac fossa, and into the thigh, passing beneath Poupart's ligament, posterior and lateral to the femoral vessels. The communication between the pelvis and the thigh is often very narrow, so that the abscess cavity has to some extent the shape of an hour-glass. The pus may reach the surface in the region of the saphenous opening, or may spread farther down the thigh under cover of the deep fascia. In some cases it is liable to be mistaken for a femoral hernia, as the swelling becomes smaller when the patient lies down, and has an impulse on coughing.

Lumbar Abscess.--Sometimes the pus travels along the posterior branches of the lumbar vessels and nerves to the lateral border of the sacro-spinalis (erector spinae) and comes to the surface in the space between the edges of the latissimus dorsi and external oblique muscles--the triangle of Petit.

In rare cases it passes through the sacro-sciatic foramen and forms a swelling in the buttock (sub-gluteal abscess); or it may pass through the obturator foramen and reach the adductor region of the thigh or even the perineum.

#Lumbo-sacral Region.#--Pott's disease in the lumbo-sacral region usually affects adults, and, on account of the breadth of the vertebral bodies and the limited range of movement in this segment of the spine, is seldom accompanied by marked symptoms or deformity. The diagnosis, therefore, is often difficult, unless good skiagrams are available. The disease may be associated with pain in the distribution of the sciatic nerve, which is liable to be mistaken for sciatica. Single or double iliac abscess frequently forms without the patient showing any characteristic signs of spinal disease. When the disease begins in childhood it may induce a permanent deformity of the pelvis, the conjugate diameter at the brim being increased, while the transverse diameter at the outlet is diminished--kyphotic pelvis, and, in females, this may lead to complications in parturition.

#Tuberculous Disease of the Sacro-iliac Joint.#--This condition may occur as a primary affection, but is much more frequently secondary to disease in the ilium, sacrum, or lower lumbar vertebrae, and is most common in adolescents and young adults of the male sex. It is attended with pain in the lumbar region, and sometimes in the buttock and along the course of the sciatic nerve. The pain is aggravated by movements, especially such as involve sudden and violent contraction of the lumbar and abdominal muscles, for example, coughing, sneezing, or straining during defecation. Tenderness is elicited on making pressure over the joint, on pressing together the iliac bones, or on attempting to abduct the limb while the pelvis is fixed. The muscles of the buttock and thigh are wasted. As any attempt to bear weight on the affected limb causes pain, the patient walks with a limp, and to save the joint he assumes an attitude which is characteristic: he throws his weight on the sound limb, leans forward, using a stick for support, tilts the affected side of the pelvis downwards, and flexes the hip and knee-joints of the diseased limb. The anterior superior spine is unduly prominent on the affected side, and the limb appears to be lengthened. Sooner or later, in most cases, an abscess forms, and the pus may reach the surface over the posterior aspect of the joint. When the pus forms in front of the joint, it may spread laterally in the iliac fossa as an iliac abscess or may gravitate downwards in the hollow of the sacrum and emerge on the buttock through the sacro-sciatic foramen--sub-gluteal abscess. Sometimes it passes into the ischio-rectal fossa or into the perineum. The presence of an abscess in the pelvis may sometimes be recognised on rectal examination. The appearance of an abscess is sometimes the first thing to draw attention to the condition.

As pain across the small of the back and along the course of the sciatic nerve may be among the early symptoms of sacro-iliac disease, the condition is liable to be mistaken for lumbago or for sciatica. From hip disease it is recognisable by noting that the movements of the hip-joint are not restricted. It is not always possible without the aid of skiagrams to differentiate sacro-iliac disease from disease of the lumbar spine, and the two conditions sometimes coexist.

The prognosis is unfavourable, particularly in cases complicated by extensive disease of the ilium with abscess formation and mixed infection.

Treatment.--In early cases the patient should use crutches and wear a patten on the foot of the sound side; in more advanced cases he must be confined to bed, and have absolute rest to the joint secured by means of extension applied to both legs, or by other apparatus. In children a double Thomas' splint or Stiles' abduction frame is a convenient appliance. Counter-irritation by blisters or the actual cautery may be had recourse to in dry cases in which pain is a prominent feature. If operative treatment becomes necessary, as it may, for removal of a sequestrum, access to the seat of disease is obtained by removing the posterior portion of the iliac bone. Cold abscess is treated on the usual lines.

#Syphilitic Disease of the Vertebrae.#--All the clinical features of Pott's disease may be simulated by gummatous disease of the vertebrae. This is usually met with in adults who have suffered from acquired syphilis; it is most common in the upper cervical vertebrae, and begins on the anterior surface of the bodies. The onset is more sudden than that of tuberculous caries, and the progress more rapid. The bone is early and extensively destroyed, but abscess formation is rare. Severe nocturnal pains are complained of, and some degree of angular deformity may develop. In almost all cases other evidence of tertiary syphilis is present, and this, together with the history and the effects of anti-syphilitic treatment, aids in diagnosis. The local treatment is carried out on the same lines as for tuberculous disease.

#Malignant Disease of the Vertebrae.#--Sarcoma is the most important of the primary tumours met with in the vertebral column. It gives rise to symptoms which are liable to be mistaken for those of Pott's disease or of arthritis deformans. The pain, however, is more intense, and the disease progresses more continuously, and is uninfluenced by treatment. The changes in the vertebrae, as seen in skiagrams, are helpful in diagnosis. The growth may encroach upon the vertebral canal and cause pressure on the cord (p. 451). In the sacrum--the most common site--the tumour implicates the sacral nerves, and causes symptoms of intractable sciatica; and the real nature of the disease is often only detected on making a rectal examination.

Secondary cancer is a common disease, particularly in cases of advanced scirrhus of the breast. It leads to extensive softening of the bodies of the vertebrae, so that they yield under the weight of the body, as in Pott's disease. Clinically it is associated with severe pain in the region of the vertebrae affected, and along the course of the nerves emerging in the neighbourhood. If paralysis occurs from the cancerous bodies pressing upon the cord (paraplegia dolorosa), it is of rapid development, often becoming complete in a few hours. When the cervical cord is compressed all four limbs are paralysed, and from interference with respiration, the condition is fatal within a few days.

#Actinomycosis#, #Blastomycosis#, and #Hydatid Cysts# also occur in the vertebrae, and are difficult to diagnose from tuberculous disease.

#Typhoid Spine.#--An acute infective condition of the vertebrae, intervertebral discs, and spinal ligaments occasionally occurs during convalescence from typhoid fever. The lumbar region is most frequently affected, and the X-rays reveal inflammatory changes in the bones, disappearance of the discs, and, in the later stages, deposits of new bone leading to synostosis of adjacent vertebrae. The onset, which may be gradual or sudden, is attended with intense pain, and tenderness over the affected vertebrae. The temperature is raised, and other signs of an acute infective process are present. In a few cases there are symptoms of involvement of the membranes and cord. With prolonged rest and immobilisation of the spine the inflammation usually subsides, but sometimes it goes on to suppuration.

#Hysterical Spine.#--This term is applied to a functional affection of the spine occasionally met with in neurotic females between the ages of seventeen and thirty, and liable to be mistaken for Pott's disease. The patient complains of pain in some part of the spine--usually the cervico-thoracic or thoracico-lumbar region--and there is marked hyperaesthesia on making even gentle pressure over the spinous processes. As the patients are usually thin, the pressure of the corset is apt to redden the skin over the more prominent vertebrae, and give rise to an appearance which at first sight may be mistaken for a projection. The general condition of the patient, the freedom of movement of the vertebral column, and the entire absence of rigidity, are sufficient to exclude tuberculosis. The condition is treated on the same lines as other hysterical affections.

#Acute osteomyelitis# of the vertebrae is a rare affection, and is met with in young subjects. It attacks the more mobile portions of the spine--cervical and lumbar--and may begin either in the bodies or in the arches. It is attended with extreme sensitiveness on movement, severe localised pain in the region of the vertebrae attacked, and a marked degree of fever. Pus usually forms rapidly, but, being deeply placed, is not easily recognised unless it points towards the surface. The infection is liable to spread to the meninges of the cord and give rise to meningitis, particularly when the disease begins in the arches. A milder form occurs, in which the main incidence is on the periosteum; the symptoms are less severe, it does not tend to suppurate, and is usually recovered from. The treatment consists in applying extension to the spine and in opening any abscess that may be detected. The suppurative form usually proves fatal, and, indeed, is often only diagnosed on post-mortem examination.

#Arthritis Deformans.#--This disease usually begins between the ages of thirty-five and forty, and attacks men who follow some laborious occupation which involves exposure to cold and wet. It is met with, however, in women who lead a sedentary life. There is sometimes a recent history of gonorrhoea, rheumatism, or other toxic disease, and occasionally the condition follows upon injury. The discs disappear, osteophytic outgrowths develop at the margins of the bodies and in connection with the transverse processes, and bridge across the space between neighbouring vertebrae (Fig. 218). The articulations between the ribs and the vertebrae show similar changes, and the ligaments of the several joints tend to undergo ossification, so that the bones are fused together.

In the early stage the patient complains of pain and stiffness in the back; later the spine becomes rigid, and gradually develops a kyphotic curve, sometimes accompanied by lateral deviation. In some cases, the curvature of the spine assumes an extreme type, the shoulders are rounded, and the head depressed, the face approximating the sternum, so that to see an object such as a picture on a wall, the patient must turn his back to it. The chest is flattened and restricted in its movements, with the result that respiration is embarrassed and becomes almost entirely abdominal. The muscles of the back, shoulders, and hips undergo atrophy, and may exhibit tremors, and the deep reflexes become exaggerated. The nerves are liable to be pressed upon as they pass through the intervertebral foramina, and this gives rise to pain and other disturbances of sensation in their area of distribution. These pains may simulate those associated with renal or gastro-intestinal affections.

The disease may simulate tuberculous caries or malignant disease. The changes in the bones are demonstrated by the use of the X-rays.

The treatment is carried out on general principles (Volume I., p. 530), but it is seldom possible to do more than arrest the progress of the disease.

#Coccydynia# is the name applied to a condition in which the patient experiences severe pain in the region of the coccyx on sitting or walking, and during defecation. The pathology is uncertain. In some cases there is a definite history of injury, such as a kick or blow, causing fracture of the coccyx, or dislocation of the sacro-coccygeal joint. These lesions have also been produced during labour. In other cases the pain appears to be neuralgic in character, and is referable to the fifth sacral and the coccygeal nerves, or to the terminal branches of the sacral plexus distributed in this region. The affection is almost entirely confined to females, and the patients are usually of a neurotic type. On rectal examination the coccyx is exceedingly tender, and it is sometimes found to be less movable than normal, and unduly arched forward. When medicinal treatment fails to give relief, the coccyx may be excised.

#Tumours of the Spinal Cord and Membranes.#--Tumours may develop in the substance of the cord (intra-medullary), in the membranes (meningeal), or in the tissues between the dura and the bone (extra-dural); or the cord may be pressed upon by a tumour originating in the vertebrae. It is seldom possible to diagnose the nature of a tumour before operation, and it is often difficult to determine in which of the above situations it has originated.

Tumours growing in the substance of the cord are nearly as common as extra-medullary growths, and as the growth is usually sarcoma, glioma, tuberculoma, or gumma, and infiltrates the cord, it is seldom capable of being removed by operation.

The great majority of meningeal tumours are primary sarcomas, and in about 25 per cent. of cases they are multiple. Hydatid cysts and fibromas are also met with in this situation, and they too may be multiple.

Extra-dural growths are comparatively rare. The forms usually met with are sarcoma and lipoma.

These extra-medullary tumours seldom infiltrate the cord; they simply compress it, and should be subjected to operative treatment before secondary changes are produced in the cord.

The symptoms vary according as the tumour presses on the nerve roots, on one half, or on both halves of the cord. Pressure on nerve roots is a characteristic sign in extra-medullary growths. It gives rise to pain, which, according to the level of the tumour, passes round the trunk (girdle-pain), or shoots along the nerve-trunks of the upper or lower limbs.

When the cord is pressed upon, intense neuralgic pain related to the segment first involved is one of the earliest symptoms, particularly in extra-medullary tumours. The pain is at first unilateral, but later becomes bilateral--a point of importance in diagnosis. The painful areas are anaesthetic, but the anaesthesia does not always reach to the level of the lesion. There may be a zone of hyperaesthesia at the upper limit of the anaesthesia, or in the area corresponding to the roots on which the tumour is situated, but there is never diffuse hyperaesthesia (V. Horsley). In intra-medullary tumours the pain is less severe, it is rarely an initial symptom, and is seldom referable to individual nerve roots.

The next symptom to appear is motor paresis, followed by complete paralysis, and later by contracture of the paralysed muscles--spastic paraplegia. In intra-medullary tumours the paraplegia is usually less complete than in those that are extra-medullary. When only one lateral half of the cord is pressed upon, the motor paralysis and loss of ordinary sensation are on the same side as the tumour, and the loss of the sense of pain and of the temperature sense is on the opposite side. Retention of urine accompanies the onset of paralysis, and later gives place to incontinence. The rectum becomes paralysed, and cystitis and pressure sores develop.

Anti-syphilitic treatment should be employed in the first instance to exclude the possibility of the lesion being of the nature of a gumma. Radical operative treatment is contra-indicated in intra-medullary and in metastatic growths, but decompressive measures may be employed for the relief of pain. In meningeal and extra-dural tumours, however, in view of the hopeless prognosis if the condition is allowed to take its course, an attempt may be made to remove the tumour by operation. It is to be borne in mind that the lesion may be two or three segments higher than the complete anaesthesia would appear to indicate; the vertebral canal, therefore, should be opened about four inches above the level of the anaesthesia.

When the tumour is not removable, the patient's suffering may sometimes be alleviated by resecting the posterior roots of the nerves emerging in the vicinity of the lesion.

#Chronic Spinal Meningitis.#--Victor Horsley (1909) described by this name a condition which gives rise to symptoms closely simulating those of a tumour of the cord. He believes it to consist in a pachymeningitis combined with a certain degree of sclero-gliosis of the periphery of the cord. The theca is greatly distended over a variable extent of the cord; the cerebro-spinal fluid is increased in quantity and is under considerable tension; and the cord itself presents a shrunken appearance. Sometimes there is thickening of the arachno-pia and matting of the nerve roots. The condition appears to begin in the lower part of the cord, and to spread up, usually as far as the mid-thoracic region. There is frequently a history of syphilis, sometimes of recent gonorrhoea, but in some cases no cause can be assigned for the lesion.

Clinical Features.--This affection is almost always met with in adults, and the earliest symptoms are pain and weakness in the legs, and sometimes a slight kyphotic projection of the spinous processes. The loss of power, which is sometimes attended with spasticity, usually manifests itself in one leg first, and later affects the other; it is progressive, and ultimately ends in complete paraplegia. The pain is not confined to the region supplied by any one nerve root, but affects a diffuse area, and the patient complains also of a sensation of tightness in the limbs. There is never absolute anaesthesia, but there is relative anaesthesia for all forms of sensation, which extends as a rule as far as the sixth or eighth thoracic root.

There are no vaso-motor phenomena, and no tendency to the formation of pressure sores. Sometimes the patient complains of pain in the spine, but this is not aggravated by movement.

Treatment.--The treatment recommended by Horsley consists in performing laminectomy, opening the theca, and washing it out with 1 in 1000 mercurial lotion. After the wound has healed, mercurial inunction over the spine is employed to hasten the absorption of inflammatory products. The administration of anti-syphilitic drugs has not proved beneficial.

#Acute Spinal Meningitis.#--The spinal membranes may become implicated by direct spread in cases of acute intra-cranial lepto-meningitis, or they may be infected from without--for example, in gun-shot injuries or in cases of spina bifida.

When the infection spreads from the cranial cavity, the cerebral symptoms dominate the clinical picture, but evidence of involvement of the membranes of the cord may be present in the form of rigidity of the cervical muscles with retraction of the neck; deep-seated pain in the back, shooting round the body (girdle-pain) and down the limbs; painful cramp-like spasms in the muscles of the back and limbs, with increased reflex excitability, sometimes so marked as to simulate the spasms of tetanus.

When the theca of the cord is directly infected the spinal symptoms predominate at first, but as the condition progresses it involves the cerebral membranes, and symptoms of acute general lepto-meningitis ensue.

Once the condition has started little can be done to arrest its progress, but the symptoms may be relieved by repeated lumbar puncture.

#Spinal Myelitis.#--The term "myelitis" is applied to certain changes which occur in the spinal cord as a result, for example, of haemorrhage into its substance (haemorrhagic myelitis); or of pressure exerted on it by fragments of bone, blood-clot, tuberculous material, or new growths (compression myelitis).

In another group of cases myelitis is a result of the action of organisms or their toxins. Syphilis is a common cause, but the condition may follow on infections with ordinary pyogenic cocci, pneumococci, the influenza bacillus or the bacillus coli.

In addition to the use of anti-syphilitic remedies, or of sera directed to neutralise the toxins of the causative organism, attention must be directed to the bladder, and steps taken to prevent cystitis and the formation of bed-sores.

CONGENITAL DEFORMITIES OF THE SPINE

#Spina Bifida.#--Spina bifida is a congenital defect in certain of the vertebral arches, which permits of a protrusion of the contents of the vertebral canal. It is due to an arrest of development, whereby the closure of the primary medullary groove and the ingrowth of the mesoblast to form the spines and laminae fail to take place. The cleft may implicate only the spinous processes, but as a rule the laminae also are deficient. The defect usually extends over several vertebrae (Fig. 219). While the protrusion varies much in size, there is no constant ratio between the dimensions of the swelling and the extent of the defect in the neural arches.

The condition is comparatively common, being met with in about one out of every thousand births. It is most frequent in the lumbar and sacral regions (Fig. 219), but occurs also in the cervical (Fig. 220) and thoracic regions. It is not uncommon to find spina bifida associated with other congenital deformities such as hydrocephalus, club-foot, and extroversion of the bladder.

Varieties.--Four varieties are usually described according to the character of the protrusion. They are analogous, to a certain extent, to the varieties of cephalocele (p. 387). (1) Spinal meningocele, in which only the membranes, filled with cerebro-spinal fluid, are protruded. (2) Meningo-myelocele, the form most commonly met with clinically, in which the cord and some of the spinal nerves are protruded, and spread out over the inner aspect of the sac (Figs. 219, 220). (3) Syringo-myelocele, in which there is a dilatation of the central canal in the protruded part of the cord. In these three forms the protrusion may be covered by healthy skin, or by a thin, smooth, translucent membrane through which the contents are visible. Frequently this thin covering sloughs or ulcerates, and permits the cerebro-spinal fluid to drain away. (4) In the myelocele, this skin, as well as the vertebral arches and membranes, is absent, and the cord lies exposed on the surface. This form is comparatively common, but as the infants are either dead born or die within a few days of birth, it seldom comes under the notice of the surgeon.

Clinical Features.--The presence of a swelling in the middle line of the back, which has existed since birth, and which contains fluid and increases in size and tenseness when the child cries, renders the diagnosis of spina bifida easy. The defect in the bone may be seen in skiagrams. The swelling is usually sessile, but may be pedunculated; it is usually possible to palpate the edges of the gap in the bones. It may be reduced in size by making gentle pressure over it, and in young children this may cause a bulging of the fontanelles. This test, however, must be employed with caution, as it is liable to induce convulsions. A meningocele, as it contains no nerve elements, may be translucent. In a meningo-myelocele the shadows of the cord and nerves stretched out in the sac may be recognised. The presence of the cord is sometimes indicated by a median furrow, and after withdrawal of some of the fluid the cord can sometimes be palpated. It is, however, often difficult to distinguish between a meningocele and meningo-myelocele.

Sometimes there are no nervous disturbances, and this is especially the case when the defect is in the lower lumbar and sacral regions below the termination of the cord. In most cases, however, there are paralytic symptoms referable to the lower extremities, the bladder, and the rectum, and there may also be trophic disturbances in the parts below. Paralytic symptoms may be absent during infancy, and develop during childhood or adolescence.

Prognosis.--Comparatively few children born with spina bifida survive longer than four or five years. The great majority die within a few weeks of birth, death being due to the escape of cerebro-spinal fluid, or to spinal meningitis following on infection. The condition in some cases remains stationary for years, but spontaneous disappearance is rare.

Treatment.--The more severe forms of spina bifida only call for palliative treatment, which consists in protecting the protrusion against infection and applying a sterilised dressing and a supporting bandage. A meningocele may be tapped with a fine needle passed through healthy skin, and the empty sac compressed by a pad of wool and an elastic bandage.

Operative treatment is seldom to be recommended in a young child unless it is otherwise viable and the swelling is increasing rapidly and threatening to burst, and there is reason to believe that the paralysis is due to pressure. The immediate results of operation are usually satisfactory, but in a large proportion of cases the child subsequently develops hydrocephalus, from which it ultimately succumbs. The hope of improvement in the motor symptoms after operation depends on the site of the spina bifida; above the twelfth thoracic vertebra there is no prospect of improvement; below this level, inasmuch as it is the tip of the conus or the cauda equina that is involved, there may be regeneration of nerve fibres and return of power in the lower extremities, and control of the sphincters may be regained. Murphy has practised resection of cicatricial or atrophied portions of the cauda, with end-to-end suture.

The term #spina bifida occulta# is applied to a condition in which there is no protrusion of the contents of the vertebral canal, although the vertebral arches are deficient. The skin over the gap is often puckered and adherent, and is frequently covered with a growth of coarse hair.

A mass of fat may project towards the surface, and when situated in the lumbo-sacral region may suggest a caudal appendage or tail (Fig. 222).

The clinical importance of spina bifida occulta lies in the fact that it is sometimes associated with congenital club-foot, and with nerve symptoms, in the form of sensory, motor, and trophic disturbances referable to the lower limbs, such as perforating ulcer, and to the sphincters. These nerve symptoms usually result from the presence of a tough cord composed of connective tissue, fat, and muscle, stretching from the skin through the vertebral canal to the lower end of the spinal cord. As this strand of tissue does not grow in proportion with the body, in the course of years it drags the cord against the lower border of the membrana reuniens, which closes in the vertebral canal posteriorly. These symptoms may be relieved by the removal of this strand of tissue from the gap in the vertebral arches, or by incising the membrana reuniens.

#Congenital Sacro-coccygeal Tumours--Teratoma.#--Many varieties of congenital tumours are met with in the region of the sacrum and coccyx. The majority are developed in relation to the communication which exists in the embryo between the neural canal and the alimentary tract--the post-anal gut or neurenteric canal. Some are evidently of bigerminal origin, and contain parts of organs, such as limbs, partly or wholly formed, nerves, parts of eyes, mammary, renal, and other tissues.

Among other tumours met with in this region may be mentioned: the congenital lipoma--a small, rounded, fatty tumour which often suggests a caudal appendage (Fig. 222); the sacral hygroma, which forms a sessile cystic tumour growing over the back of the sacrum, and is believed to be a meningocele which has become cut off in utero by the continued growth of the vertebral arch; dermoids, sarcoma, and lymphangioma.

The treatment consists in removing the tumour, as from its situation it is exposed to injury, and this is liable to be followed by infection. From the position of the wound, and the fact that many of these tumours extend into the hollow of the sacrum and therefore necessitate an extensive dissection, there is considerable risk from infection, especially in young children. The risk is increased when the tumour communicates with the vertebral canal.

#Congenital Sacro-coccygeal Sinuses and Fistulae.#--The post-anal dimple, a shallow depression frequently observed over the tip of the coccyx, may be due to traction exerted on the skin at this spot by the remains of the neurenteric canal, or by the caudal ligament of Luschka. Sometimes the integument is retracted to such an extent that one or more sinuses are formed, lined with skin which is furnished with hairs, sweat, and sebaceous glands. The bursting of a dermoid, or its being incised in mistake for an abscess, may result in the formation of such a sinus, which fails to heal and may persist for years.

In some cases the depression communicates with the vertebral canal, constituting a complete sacro-coccygeal fistula, which may be lined with cylindrical or ciliated epithelium.

From the accumulation of secretions and subsequent infection, these conditions may be associated with a persistent offensive discharge, and they are liable to be mistaken for ano-rectal fistulae. They are best dealt with by complete excision, and as primary union cannot be expected, the wound should be treated by the open method.

XVIII. DEVIATIONS OF THE VERTEBRAL COLUMN

LORDOSIS--KYPHOSIS--SCOLIOSIS

Three main deviations of the vertebral column are described: Lordosis, in which it is unduly arched forwards; Kyphosis, in which it is unduly arched backwards; and Scoliosis or lateral deviations, in which the spine deviates to one side of the middle line.

#Lordosis# or anterior curvature of the spine with the convexity forwards, is chiefly met with in the lumbar region as an exaggeration of the natural curvature. A minor degree of lordosis sometimes occurs as a peculiarity in the conformation of the individual and may be present in several members of the same family; also in street-hawkers and others who carry weights suspended in front of them; in very obese persons; in those who suffer from large abdominal tumours, such as fibroids; and in pregnant women. In its more marked and typical forms it is met with as a compensatory deviation when the pelvis is tilted forwards in association with flexion of one or of both hip-joints. Illustrations of this association are found in congenital dislocation of the hip, particularly when this is bilateral, in tuberculous disease of the hip when recovery has occurred with ankylosis in the flexed position, and in Charcot's disease of the hip. The resuming of the erect position with tilting of the pelvis from flexion at the hip is necessarily attended by an exaggeration of the forward curvature of the lumbar spine. Its relationship to the erect posture is readily demonstrated by noting its partial or complete disappearance when the patient is sitting and the tilting of the pelvis is thus eliminated.

Lordosis elsewhere than in the lumbar segment is met with as a compensatory deviation to kyphotic or backward curvature of the spine: in Fig. 211, for example, a kyphotic projection in the mid-thoracic region has led to a lordosis in the cervico-thoracic segment above, and in the thoracico-lumbar segment below, the forward curve being again a necessary outcome of the resuming of the erect posture. The absence of a compensatory lordosis in such a condition would warrant the inference that the patient had been bed-ridden.

#Kyphosis# or posterior curvature of the spine with the convexity backwards, is met with at all periods of life, and results from a wide range of conditions.

In infancy it is a common result of general debility. The child need not appear to be badly nourished, it may even be fat and look well, but there is a want of muscular vigour such as should enable it to hold itself erect in the sitting posture. It is to be noted that a considerable degree of kyphosis may exist without interference with the normal outlook in the erect posture, and, therefore, the question of compensatory curvature does not arise. In the adolescent a degree of kyphosis in the cervico-thoracic region is common, and is spoken of as "round shoulders"; it is largely a matter of habit that requires correction by the governess or nurse. Among agricultural labourers and gardeners after middle life, and in the aged, this type of curvature is of common occurrence and is evidently associated with their occupation. An exaggerated form of the same cervico-thoracic kyphosis is met with in patients suffering from progressive muscular atrophy, poliomyelitis, osteitis deformans of Paget, acromegaly, and many allied conditions in which either the muscular or the mental vigour is deficient, and the patient adopts the cervico-thoracic kyphosis as the attitude of rest.

Another type of diffuse kyphosis without compensatory curvature is met with in arthritis deformans, in which the kyphosis is associated with the disappearance of the intervertebral discs and ankylosis of the vertebral bodies by bridges of new bone in the position of the anterior common ligament.

Partial or localised kyphosis, on the other hand, is the result of organic changes in the bodies of the vertebrae of the segment of spine affected. It is most often met with in Pott's disease in which the extent of the curve depends on the number of bodies affected, and its degree on the amount of destruction that the bodies have undergone. With the resumption of the erect posture, and in order that the eyes should look directly forwards, a compensatory lordosis is acquired above and below the segment that is the seat of kyphosis (Fig. 211). A similar but less marked type of kyphosis may follow upon compression fracture of the spine--in the condition known as traumatic spondylitis; and as a result of other lesions, such as osteomalacia, or malignant disease, in which the bodies undergo softening and yield, so that the spinous processes project posteriorly.

SCOLIOSIS

#Scoliosis# or lateral curvature is by far the commonest and most important deviation of the spine. The student will obtain a clearer conception of the nature of this deformity if we consider in the first place those types for which an obvious explanation is available.

Static scoliosis, for example, when one leg is shorter than the other, the pelvis is tilted down on the short side, the thoracico-lumbar spine deviates laterally to the normal side, and to restore the equilibrium of the trunk the cervico-thoracic spine deviates again in the opposite direction. The causes of one leg being shorter than the other are numerous and varied; they include such conditions as unilateral congenital dislocation of the hip, fractures united with overriding of the fragments, diseases of the joints, e.g., hip disease, or of the bones, especially such as interfere with the function of ossifying junctions; and acquired deformities such as unilateral flat-foot, knock-knee, or bow-leg. Clinically, this type of scoliosis is identified by observing that when the patient sits down the deviation of the spine disappears; it is relieved or got rid of by raising the sole and the heel of the boot on the short side, and, if required, by inserting an "elevator" inside the boot.

When there is shortening of the muscles on one side of the trunk there develops a lateral curvature of the spine with its convexity to the normal side; a good example of this is afforded in cases of infantile hemiplegia (Fig. 224) in which the deviation affects the entire column: a localised form is seen in congenital wry-neck, in which the convexity of the cervico-dorsal curve is on the side of the normal sterno-mastoid with a compensatory deviation to the opposite side in the spine below (Fig. 272). Unilateral paralysis of muscles acting on the trunk may also cause a lateral deviation of the spine, as is well seen in paralysis of the trapezius, which results in a cervical scoliosis with the convexity to the non-paralysed side.

Asymmetry of the thorax, such as may follow on empyema with defective expansion of the lung, causes a lateral deviation of the dorsal spine with the convexity towards the normal side.

Attitudes adopted to relieve pain, such as that caused by sciatica, sacro-iliac or hip disease, in which the weight of the body is transferred to the normal side, cause a scoliosis similar to that due to irregularity in the length of the lower extremities, and is similarly made to disappear when the patient sits upon a flat surface.

Malformation or disease of the vertebrae themselves is a well recognised cause of scoliosis; the best known, as it may be also the most severe and the most intractable, is that due to rickets, under which heading it has already been described (Fig. 225). In a few cases a rudimentary wedge-shaped vertebra has been revealed by the X-rays.

In all of these forms or types of scoliosis the primary cause must be searched for and when found is made the first object of treatment; the treatment of the scoliosis as such is on the same lines as in the postural variety that now falls to be described.

#Habitual or Postural Scoliosis.#--These names have been given to the type of scoliosis that develops in young girls and for which there is no mechanical explanation.

It is most frequently met with in rapidly growing girls of poor physique who are overworked at school or lessons, or on commencing an apprenticeship for which they are physically unfit. In some cases there is nasal obstruction from adenoids, in others the development and free play of the chest are interfered with by tight and ill-fitting garments; in all of them the muscular system is weak and the muscles of the trunk do not take their proper share in maintaining the erect posture. The most important determining factor would appear to be the habitual or repeated assumption of faulty attitudes, partly from carelessness, largely from fatigue, in order to relieve the feeling of tiredness in the back. So far as is known, the condition does not occur in communities living under aboriginal conditions. In some cases there is a hereditary tendency to scoliosis; we have seen it, for example, in a father and his daughters.

The excessive use of one arm in the carrying of weights, the habit of resting on one leg more than the other, or the assumption of a faulty attitude in writing or in playing the piano or violin, doubtless, determine the seat and direction of the curvature, and, when it has once commenced, tend to aggravate and to perpetuate it.

It is probable that the greater frequency of the primary curvature towards the right is associated with the more general use of the right hand and arm, although primary curvatures towards the left are not confined to left-handed persons.

Morbid Anatomy.--The original deviation or "primary curve" is usually in the thoracic region, and has its convexity directed towards the right side. To re-establish the equilibrium of the column, "secondary" or "compensatory" curves, with their convexities to the left, develop in the regions above and below the primary curve. It has been proved experimentally that lateral deviation of the spine is inevitably accompanied by rotation of the vertebrae around a vertical axis, in such a way that their bodies look towards the convexity of the curve, while their spines, laminae, and articular processes are directed towards the concavity (Fig. 226).

As the deformity increases, the individual vertebrae are distorted, the bodies becoming wedge-shaped from side to side, the base of the wedge looking towards the convexity of the curve, while the narrow end looks towards the concavity (Fig. 228). As the spine, laminae, and articular processes also undergo alterations in shape, a line uniting the tips of the spinous processes does not furnish an accurate index of the degree of lateral deviation but minimises it considerably. The muscles and ligaments are altered in length in accordance with the changes in the shape and position of the bones.

In the thoracic region, the ribs necessarily accompany the transverse processes, so that on the side of the convexity they form an undue prominence behind--the "rib-hump" (Fig. 227), while on the side of the concavity the chest is flattened and the ribs crowded together so that the intercostal spaces are diminished or even obliterated. The converse--flattening on the side of the concavity--is seen on the front of the chest.

The general shape of the thorax is altered: on the side of the convexity it is longer and narrower than normal and its capacity diminished, while on the side of the concavity it is shorter and broader and its capacity is increased.

The viscera are distorted and displaced in accordance with the altered shape of the thoracic and abdominal cavities. The twisting of the spine causes the patient to lose in stature, and the limbs appear to be disproportionately long. In advanced cases the pelvis becomes obliquely contracted--a deformity known as the scoliotic pelvis.

In spite of the marked deformity the spinal cord is never compressed.

Clinical features.--The development of scoliosis is always slow and insidious. As a rule, attention is first attracted to the deformity about the age of puberty, but in most cases it has existed for a considerable time before it is observed. The patient--usually a girl, although it also occurs in boys--is easily fatigued, has difficulty in keeping herself erect, and often complains of pain in the back and shoulders and along the intercostal spaces on the side of the convexity. To relieve the muscles of the back she is inclined to lounge in easy and ungainly attitudes.

The most common form of scoliosis met with in adolescents is a primary thoracic curvature with its convexity to the right (Fig. 227), and with more or less marked compensatory curves towards the left in the lumbar and cervical regions. The thoracic spines lie towards the right of the middle line. On account of the prominence of the ribs, the right scapula is projected backwards, and its inferior angle is on a higher level and farther from the middle line than that of the left scapula. The right shoulder seems higher than the left, and is popularly said to be "growing out"--a point which is often first observed by the dressmaker. The right side of the back is unduly prominent, while the left side is flattened. A deep sulcus forms in the left flank below the costal margin, and the space between the arm and the chest wall--the "brachio-thoracic triangle"--on the left side is much more marked than on the right; and the left iliac crest usually projects upwards and backwards. As seen from the front, the right side of the chest is flattened, while the left side is abnormally prominent, the breasts are asymmetrical, and the right nipple is on a higher level than the left.

In aggravated cases, the patient may suffer from shortness of breath on exertion, and the respiratory difficulty may react on the heart, causing dilatation of the right side, palpitation, and precordial pain.

Sometimes, and particularly in males, the primary curvature is in the lumbar region, and the convexity is to the left. The deviation of the lumbar vertebrae produces a prominence in the left flank which masks the outline of the iliac crest on that side, while the right flank shows a deep furrow and the right half of the pelvis is unduly prominent. There is a slight compensatory curve to the right in the thoracic region, and the right side of the chest projects backwards. The brachio-thoracic triangle is much more marked on the right than on the left side.

Diagnosis of Adolescent Scoliosis.--In many cases the patient is brought to the surgeon on account of pain and weakness in the back before any distinct deviation has developed, and, unless a careful examination is made, the real cause of the symptoms is liable to be overlooked.

The patient should be stripped and examined in a good light in various attitudes; for example, standing in an easy position, standing as straight as she can, and sitting on a flat stool. She should also be asked to read from a book and to write, in order to exhibit her usual attitudes. In early cases, an inequality in the level of the angles of the scapulae is often the only physical sign to be detected. It should also be observed whether the line of the spines is altered when the patient hangs from a horizontal bar or trapeze. Any backward projection of the ribs on one side is rendered more obvious if the patient folds the arms across the chest and bends well forward, while the surgeon looks along the back from behind.

Pott's disease may be excluded by the absence of rigidity. Any mechanical cause of deviation of the spine, such, for example, as inequality in the length of the limbs or contraction of the chest after empyema, must be sought for. Scoliosis that depends upon inequality in the length of the limbs or tilting of the pelvis, disappears on sitting.

Treatment.--The treatment of postural scoliosis implies a comprehensive programme, including attention to the general health, habits, and exercises out of doors and in the gymnasium, clothing, etc., all requiring supervision over a period of months, or even of years. The object of the treatment is to correct the deformity before the position has become fixed by rotation of the vertebrae and alteration in their shape. The child must not be allowed to assume awkward attitudes while reading, writing, or playing the piano; she must sit on a low chair, the seat of which slopes slightly downwards and backwards, and the back rest of which reaches as high as the shoulders, and is at an angle of 100 deg.-110 deg. with the seat. The feet should rest on a sloping stool, and when the child is reading or writing, a desk sloping at an angle of 45 deg. should be used. In weakly girls approaching the period of puberty, special care should be taken to avoid compression of the trunk by tight corsets. Adenoids or other sources of respiratory obstruction must be removed; and if the patient is myopic she should be provided with suitable glasses. Standing should be avoided, as there is a great tendency to throw the weight on to one leg; but walking, running, and other exercises which bring both sides of the body into action equally are permitted under supervision. Horse-riding is a suitable form of exercise, but girls must ride astride; cycling is not to be recommended.

In mild cases--that is, those in which the curvature is obliterated when the patient is suspended--the prophylactic measures above mentioned must be rigidly enforced, and gymnastic exercises should be prescribed. The exercises should not be commenced, however, until, after a period of rest in bed, all pain and feeling of tiredness in the back have disappeared.

In cases in which the curvature is not affected by suspension, the deformity is usually permanent, but by suitable exercises it may be prevented from becoming worse, and the patient may be educated to disguise it to a considerable extent. Training is also directed towards regaining the muscular sense; with the eyes shut before a mirror, the child should endeavour to assume the correct posture; on opening the eyes, the faulty attitude is seen and corrected. Forcible correction by means of successive plaster jackets, applied in the flexed position, somewhat on the lines employed by Calot in Pott's disease, has yielded results which may be described as encouraging. Only in very advanced cases should the patient be allowed to wear a supporting jacket; such appliances have no curative effect, and can only be expected to relieve symptoms.

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Exercises for Lateral Curvature.--The particular exercises given must be carefully selected to meet the indications present in each case, the movements prescribed being designed to strengthen the weak muscles and ligaments, to increase the mobility of the spine as a whole, and to correct the deviation that exists. The exercises should be taken twice daily, preferably in the morning and afternoon, and after each spell the patient should rest for an hour, lying flat on the back. During the exercises the breathing should be carefully regulated, and at the end of each movement one or two deep breaths should be taken. Each movement should be carried out slowly, the number of times it is repeated varying from four to twelve or more, according to the nature of the exercise and the strength of the patient. The exercises should be stopped if the patient feels fatigued. Hot-air baths and massage are useful adjuvants to all forms of exercise.

#Special Exercises for Thoracic Curvature with convexity to right.#--1. Stand with arms by side; palms directed forward; shoulders braced back. This is referred to as the "best standing position" or original position. 2. Slowly raise arms from sides until level with shoulders, with palms directed forward; carry left arm straight upward--"the keynote position." Then slowly lower left arm to level of shoulder; lower both arms into original position. 3. Assume keynote position: slowly bend body forwards at hips until stooping position is reached, with legs kept quite straight, head bent slightly backwards, and eyes directed forward. Gradually return to keynote and original positions. 4. Keynote position: slowly bend whole spine to right; resume keynote and original positions. 5. Keynote position: turn body forward sideways. 6. Keynote position: rise on to balls of toes. 7. Keynote position: rise on to balls of toes; bend knees; back to original position in reverse order. 8. Patient suspended from bar or rings, the left end of the bar or left ring being three inches higher than the right. (a) Draw right knee upwards and forwards against resistance. (b) Draw legs apart against resistance. (c) Draw legs together against resistance. 9. Patient lying on back. (a) Bend right knee- and hip-joints against resistance. (b) Extend right knee and hip against resistance. (c) Rotate right hip against resistance. 10. Patient lying on face with pillow under chest; slowly raise arms to keynote position. While limbs are firmly held by a nurse, raise the body backwards and to the right. 11. Same position: make swimming movements. 12. Patient astride a narrow table or chair, without a back. (a) Repeat exercises 3, 4, 5, and 11. (b) Bend body forwards, backwards; and rotate to right and left against slight resistance made by nurse grasping patient's shoulders.

Klapp's "four-footed" Exercises.--Rudolf Klapp has devised a series of exercises designed to strengthen the muscles and ligaments of the spine, and to increase the mobility of the column. To take the weight of the body off the spine, and to render both ends of the column mobile, these exercises are carried out in the "all-fours" attitude, the patient crawling in imitation of a quadruped, that is, in such a way that the hand and knee of one side are approximated, while those of the other side are separated; in other words, the hand and knee of one side should not move forward simultaneously (Fig. 230). With each step the spine is curved laterally, the concavity of the curve being towards the side on which the hand and knee are approximated. The exercises, for a case of dorsal curvature with the convexity to the right, for example, are graduated as follows: (1) The child crawls in a straight line till he has acquired the "quadruped gait"; (2) with each step forward the head is inclined towards the side on which the hand and knee are approximated; (3) at each step the hand and knee which are wide apart are brought over and cross the limbs on the other side; (4) to open out the concave left side, he crawls in a circle towards the right. The exercises are practised morning and afternoon for from fifteen to sixty minutes at a time. If there is a marked double curve, it is best neutralised by imitating the "pacing" action of a quadruped, i.e., the limbs of the same side moving forward together. The hands, knees, and toes should be protected by suitable gloves and leather pads. Hot-air baths and massage are useful adjuvants to the exercises.

Abbott has introduced a method of treatment applicable to cases in which the deformity has become permanent. Under general anaesthesia, the patient being slung in a bracket-frame with the spine flexed, the curvature is over-corrected and a plaster-case is then applied to maintain the attitude; the plaster-case is renewed at intervals of two or three months.