Treatise on diseases of the bones

Preface

The admirable Lectures on the Diseases of Bone, with which Mr. Abernethy commenced his Anatomical and Physiological course, first incited me to the study of this subject. Observation, continued with some diligence through many years, and, in a large field of experience, has enabled me to accumulate the materials upon which the present volume is founded. The size of the volume bears no proportion to the number of the facts out of which it is constructed. For in this, as in other scientific investigations, the first object has been to obtain the facts, and the second to interpret them rightly for the conclusions they warrant. This I have endeavored to do, but with the result, I am aware, of leaving some of the morbid phenomena of bone uninterrupted, even unnoticed, for the reason that they were to me unintelligible. And I am induced to submit the work in its incomplete state, rather than detail in it characters of disease from which, in consequence of not understanding them, I should not be able to deduce either pathological conclusions or indications of treatment.

I venture to think that others have experienced the difficulty which I .have felt, in the attempt to arrange and explain the subjects to be comprehended in a Treatise on the Diseases of the Bones : otherwise, in an age remarkable for the fulness of its scientific literature, it might be expected that such treatises would have been produced. But the only works possessing this character, of which I have knowledge, are the Treatises of Petit, published in 1705, and of Boyer, in 1803.

The liberal feeling, which happily prevails in our profession, is mani- 1*

VI PREFACE.

fested through the following pages in the use that has been allowed me of the facts which others have observed. My acknowledgments on this head are sincerely offered to my colleagues at St. Bartholomew's Hospital. Especially to Mr. Lawrence these acknowledgments are due. Associated with him for many years, I have largely participated in the benefit he has conferred upon all around him, by the example of his untiring zeal and fidelity of observation, and by the liberality with which he never fails to communicate knowledge to all who are in search of it. I am also desirous of expressing to my able colleagues, Mr. Paget and Dr. Baly, my thanks for assistance in the preparation of this work.

It is necessary to observe, that notwithstanding the references, which will be found in the following pages, to another volume, containing " Illustrations of the Effects of Disease and Injury of the Bones," the two works are, in all other respects, wholly distinct. The volume of Illustrations contains, with the descriptions of the plates, full explanations of the subjects to which they relate, so that, in respect to these subjects, it is a complete and an independent work.

INTRODUCTION,

GENERAL CONSIDERATIONS ON THE DISEASES OF BONE.

It is probable that Jean Louis Petit, in his " Treatise on the Diseases of the Bones," first observed the analogy hi their morbid changes to those of the soft parts of the body. Mr. Hunter, adopting the same view of the subject, represents " the bones in the causes of many of their diseases, in the termination of them and in their restoration, as similar to the soft parts.*" Mr. Abernethy, following out the same doctrine, referred to the phenomena which bone presents in disease as the proof of its vital organization.! Experience has proved the correctness of these views, and, accordingly, they are made the foundation of the following Treatise.

Although it is true, that the diseases of bone are analogous to those of soft parts, yet they have their peculiar characters ; for in bone, as in other tissues, the rule holds that diseases are modified by the structure and vital properties of the part they attack.

Diseases of bone are generally characterized by slowness of progress. And it is equally so, whether the process tends to the advance or the recession of disease. Thus the exfoliation of the smallest piece of dead bone often requires many months for its completion ; and a much longer time is required for the osseous union or anchylosis of the surfaces of bone, which, in the progress of disease in the spine, or in a

* Lectures. t Lectures .

yill INTRODUCTION.

large joint, are brought into contact by destruction of the intervening tissues. Again, when the internal organization of a bone is deranged as in the softening of it from scrofula, even with the help of every strengthening influence upon the constitution, the reparation of the diseased bone is so tedious a process, that too frequently, from impatience in the treatment, sufficient time is not allowed for the bone to become again firm, and thereby fit for its functions.

Eone is one of the less vascular tissues of the body ; yet it readily inflames, and as readily throws forth granulations ; and in the reparation of its fractures, the osseous tissue itself takes a much larger share in the work of reparation than either the periosteum or medullary membrane. A more interesting view is not exhibited to the unaided sight of the pathologist than that of the changes which ensue upon an exposed liv-ing and healthy bone. First, its surface becomes of a faint red or pinkish tint, from the afflux of blood to its vessels ; then, bright red dots and streaks appear in the bone, which are the immediate precursors of the granulations from its tissues. These granulations appear as minute conical or round, soft papillae rising from the bone. When slightly touched, they freely bleed, and evince sensibility. Next, the granulations from the bone coalesce with those from the surrounding parts, and in this way the bone again becomes possessed of a covering of soft tissues.

Bone possesses in its healthy state but little sensibility. But under circumstances of disease, its sensibility often becomes wonderfully exalted. Thus I have witnessed the manifestation of pain as acute from the penetration of an inflamed bone by a saw or trephine as from the incisions of inflamed soft parts. We observe, moreover, the granulations from diseased bone participating in' the morbid sensibility of its tissue.

Such being the vital properties of bone, it is very liable to disease ; and its diseases are many, when compared with the diseases of muscle, tendon, or nerve, or indeed of any other organ or tissue.

In respect to its original formation, development, and growth, bone is amenable to the same disturbing influences as the soft organs and tissues. Accordingly, there occur in bone congenital defects in out-

INTRODUCTION". IX

ward form, as well as in internal organization ; thus, in a child bom with vascular hypertrophy, of the character of naevus, extending through the soft parts on one side of the cranium and face, the bones were correspondency affected ; they were found to be very thick and spongy, and excessively vascular — they presented the characters of naevus in the osseous tissue.*

"Whatever may be the source of the symmetry of diseases in soft parts, its influence extends to the osseous system. Exactly similar morbid conditions are constantly observed in the corresponding bones of the opposite sides of the body ; also in the halves of single bones. Thus the two thigh bones are often enlarged, indurated an d roughened on then surfaces, in so precisely the same manner and degree that not a morbid character can be pointed out in one of them which has not its fellow in the other ; and in the lateral halves of the frontal bone, identical characters of disease are often observed. In animals, the evidences of symmetrical morbid action are even more remarkable than in man. In the museum of the College of Surgeons there is the pelvis of a lion, which belonged to Mr. Hunter, exhibiting on its opposite sides the effects of hiflammation in the periosteum so perfectly alike, that not a rouglmess, eminence, or hollow can be detected on one side which is not exactly repeated on the other. Even the morbid growths from bone have appeared symmetrically ; thus there are instances of exostoses growing of the same size and form, and in the same situation, from the corresponding bones on the opposite sides of the body.

It can scarcely be stated that the bones participate in all the disorders of the system, which directly give rise to depravation of the fluids circulating through the soft tissues, and, in consequence, to changes in then* component elements. "Whatever peculiar immunities from disease the bones evince, are, it may be presumed, owing to the character of their organization, in respect to the earthy constituents so largely entering into then composition. There are, however, instances in which the bones, participating in the general disorders of the system, do undergo changes in their elements, and throw forth morbid products of the same character as those occurring at the time in the softer tissues of the body. Thus in gout, the earthy phosphates in the

* Museum of St. Bartholomew's Hospital, First series, No. 54.

X INTRODUCTION.

bones have diminished, peculiar products have been thrown forth from them, but they were such as are characteristic of the gouty constitution*.

It is a peculiar feature in the morbid history of bone, that the irritation of disease, however excited in it, is so commonly followed by the action of forming osseous substance among the surrounding soft parts, some of these being more prone to this action than others ; hence, the ossification ensuing in the various structures adjacent to diseased, or injured, bones. Here, moreover, it may be well to regard in one view the whole series of ossifications and osseous productions arising either as distinct diseases, or as the consequence of disease in their neighbourhood. Morbid ossifications and osseous productions may be arranged under the following heads : —

1. Unorganized masses of calcareous salts, found in various tumors, especially in the fibrous tumours of the uterus, also constituting the apparent ossifications in the coats of arteries.

2. Ossifications of original tissues, as of fibrous membrane, tendon, muscle, &c. These are, probably, but the ossifications of one tissue, the cellular, a component of all these structures.

Fibrous membranes are remarkably prone to ossification ; one example of which, among many, is the long-enduring ulcer upon the leg, followed by ossification of the periosteum beneath the ulcer and around it, accompanied by ossification of the inter-osseous ligament between the tibia and fibula, often converting it into a thick plate of bone. The character of its organization is not the sole cause of the tendency of fibrous membrane to ossify. Its vital properties, and its locality in connexion with the purposes it serves, are also to be taken into account in explanation of the exception that some fibrous membranes, as the muscular aponeuroses, or fasciae, very rarely ossify. So in respect to the pericranium, which in its structure is not distinguishable from the periosteum of

* Chemical Composition of Concretions from Gouty Bones, Marchand, Journal f. Pract. Chemie. Oct. 1842.

Urate of Soda . . - . . 34-20

Urate of lime Carbonate of lime .

Chloride of sodium Water .

Animal substance ♦ Loss

7.68 14-12

680 32-53

2-37

100-0

INTRODUCTION. XI

other bones ; yet the ossification of its texture does not occur. Osseous tumors, it is is true, are found upon the cranium, but they have originated in the bone, not in the pericranium.

All these ossifications of original tissues, when completed, exhibit in the miscroscope, in different instances, more or less of the characters of true bone.

3. Growths of perfect bone. Most of these are productions from orioinally formed bone, but they are not invariably so : some of these growths are found in cellular tissue, and have no connexion with the adjacent bones. The osseous tumours growing from' bones are of three kinds : one consists in a circumscribed hypertrophy of the bone from which the tumor grows ; this is not preceded by cartilage, it is usually cancellous, and its composition is, the same as true bone. Another osseous tumor growing frombone is that which is of most frequent occurrence, the genuine exostosis, which is preceded by the formation of cartilage, and 'com-- posed of true bone, and is usually a local malady of an innocent nature. The third form of osseous tumor growing from bone includes varieties in respect to its composition and character, and some of these exhibit features of malignancy. One of the most conspicuous of such growths is the Osteoid Tumor of Muller.

Many, and remarkably varied, are the characters of disease in bone ; yet it is not to be doubted that each of its morbid changes is the definite character of but one disease. For example, the thickenings, indurations, and ulcerations of bone exhibit various features in correspondence with the variety of the causes producing them. So with respect to the syphilitic worm-eaten ulcer of bone, its characters are so distinct that no other disease can be mistaken for it ; but there are varieties in the syphilitic ulcer of bone corresponding, Mr. Paget has observed, with the varieties of the syphilitic eruption and ulcer in soft parts.

Bone holds a high place among the animal structures, in respect of the provision made for its reproduction when lost by injury or disease. If a portion of tendon, or muscle, perishes and sloughs away, no reproduction of it ensues. The portion of bone, on the other hand, which perishes and exfoliates, is, under certain circumstances, replaced. Indeed it may be affirmed, that no where else in the animal body does so perfect an instance of reproduction occur as in certain eases of necro-

XU INTRODUCTION.

sis, where the shaft of a bone with its compact walls, cancellous texture, medullary tube, membrane, and medulla, are all reproduced with every essential feature of their original organization.

Experiments in animals have not accomplished so much for the elucidation of the reparative processes of bone in man as might probably have been expected. The circumstances attendant on the fractured or necrosed bone, in man, are essentially different from those of the experiment of breaking, or causing the death of a bone in animals. Thus, around the fractured bone of an animal, the deposit of cartilaginous and osseous substance, which has been designated provisional callus, is of uniform occurrence. But, in the human subject, no such cartilaginous and osseous deposit uniformly takes place around the fractured bone ; here, therefore, it is not an essential part of the reparative process. Also, with respect to the production of necrosis by experiment in animals, the condition of the surrounding soft parts is so materially different from the condition of these parts preceding and accompanying the death of the shaft of a bone in man, that, in consequence, the features of the reparative process in the two cases are essentially different. It has, therefore, been incorrectly assumed, that because such is the reparative process of fracture, or necrosis, in animals, it must be so likewise in man.

ARRANGEMENT OF THE SUBJECTS

Chap. I. — Hypertrophy of Bone. Atrophy of Bone

II. — Neuralgia of Bone.

III. — Inflammation of Bone.

Enlargement of Bone, \

a. By expansion of its Tissue.

b. With induration of its tissue.

e. By Osseous Deposits on its Surface.

IV.— Suppuration in Bone.

V. — Caries.

VI. — Ulceration of Bone.

VII. — Death of Bone : Necrosis.

Introduction

Analogy in the diseases of bone to those of soft parts ....

Diseases of bone of slow progress - s . . . .

Vascular character of bone, its liability to inflammation, phenomena of its granulating process .........

Sensibility of bone, its exaltation by disease .....

Many diseases of bone by comparison with other organs and tissues

Congenital defects of the outward form and internal organization, nsevus in bone

Symmetrical morbid actions in bone ......

Peculiar immunities from disease in bone, owing to its earthy constituents

Morbid ossifications and osseous productions, the consequence of the irritation of disease in bone .........

Arrangement of morbid ossifications and osseous productions

Great variety in the characters of disease in bone ; every disease in bone its definite character .........

Bone compared with other structures, in respect to the provisions for its reproduction ...........

Experiments in animals, failure to illustrate the reparative processes of bone in man

PAGE vii vii vm viii viii viii ix ix

x x

XI

xii

Chapter I. Hypertrophy And Atrophy Of Bone

Hypertrophy of bone

Examples of hypertrophy .

Influence of remedies on hypertrophy

Hypertrophy of the bones of the face

Hypertrophy of the bones of the lower extremity, consequences of it

Circumscribed hypertrophy simulating exostosis

Atrophy of bone ....

Causes of atrophy ....

Atrophy with defective growth

Defective growth of bone from disease

Defective growth in bones of the lower extremity, its consequences

CONTENTS. XV

Chapter II. Neuralgia Of Bone

, PAGE

History of the affection ........ 32

Neuralgia simulating inflammation, abscess in hone . . . .32

Diagnosis betAveen neuralgia and inflammation of bone . . . .32

Examples of neuralgia of bone ....... 33

Chapter III. Inflammation Of Bone

Vascularity, sensibility of inflamed bone ...... 37

Morbid products from inflamed bone ...... 37

Reciprocal actions of disease in bone, periosteum, and medullary membrane . 38 Enlargement of bone by expansion of its tissue ..... 38

Characters of expanded bone ....... 38

Enlargement of bone, with induration of its tissue . . . .39

Characters of indurated bone . . ..... 39

Causes of induration of bone ....... 40

Changes in the articular ends of bone from rheumatism . . . .41

Influence of medicines upon induration of bone ... 41

Enlargement of bone by osseous deposits on its surface . . . .41

Rheumatic inflammation of periosteum the frequent cause of these deposits . 42 Difficulty in the diagnosis of the various enlargements of bone . . .42

Enlargement of the cranial bones not the effect of ossification of the pericranium 43 Nervous affections coincident with enlargements of the bones of the skull . 43

Epilepsy, insanity, tic doloureaux — their connexion with enlargements of the bones of the skull ......... 43

General considerations on the treatment of inflammation of bone . . 44

Principles of treating inflammation of bone . . . . .44

Remedies for inflammation of bone . . . . . . .44

Local remedies ... ...... 44

Internal remedies, iodide of potassium, its efficacy . . 44

Influence of iodide of potassium on the syphilitic affections of bone . . 45

Influence of mercury upon the acute affections of bone . . . .45

Counter-irritation, its influence upon the painful enlargements of bone . . 46

Considerations regulating the use of counter-irritation . . . .46

Chapter IV. Suppuration In Bone

Abscess in bone, its distinction into circumscribed and diffused . . .48

Character of the circumscribed abscess ...... 48

Circumscribed abscess preceded by tubercle in bone . . . .48

XVI CONTENTS.

PAGE

Circumscribed abscess, mode of its enlargement . . . . .50

Diffuse suppuration in bone, its formidable character .... 50

Causes of diffuse suppuration in bone, example of it after amputation . . 50 Diffuse suppuration in bone, its combination with suppuration in veins, purulent

deposits in distant parts . . . . . .51

Obscurity in the symptoms of diffuse suppuration in bone, how arising, example of

it in the humerus ......... 51

Diffuse suppuration in bone accompanied by necrosis, example of it in the tibia . 52

Cases illustrating the history of inflammation in the medullary membrane . 53

Diagnosis of abscess in bone ....... 55

Treatment of suppuration in bone ....... 57

Consideration of the measure of perforating the bone for the discharge of matter

Mode of perforating a bone ........ 58

Consideration of the perforation of the outer table of the skull, for the discharge of

matter from its diploe ........ 59

Combination of suppuration in the diploe, with necrosis of the outer table of the

skull 59

CHAPTER Y.

ON CARIES.

Definitions of caries Varieties of caries .

Phenomena of caries Diagnosis qf caries .

Treatment of caries .

Influence of depletory remedies on caries Natural processes of cure of caries, considerations respecting the operation of moving carious bone .......

Incisions of the soft parts covering carious bone — effect of local applications to

61 61 61 62 63 63

63 64

Instances of caries unsuited for operation ...... 65

Chapter VI. Ulceration Of Bone

Ulceration of bone analagous to ulceration of soft parts . . . .67

Varieties of ulcer in bone . . . . . . . .67

Characters of ulcerated bone ....... 68

Ulceration of bone, a primary disease in the vertebra?, in the articular surfaces of

History of ulceration of the head of the femur ..... 69

Ulceration of the articular surfaces of bones in the progress of the inflammatory

disease of joints, its characters and consequences . . . .69

Reparation of ulcerated bone ....... 70

Eeproduction of the cancellous substance of bone removed by ulceration — osseous

CONTENTS.

xvu

Reproduction of the compact substance of bone removed by ulceration Treatment of ulceration of bone ....

Local remedies applicable to ulcerated bone Influence of counter-irritation on ulcerated bone Phagedenic ulceration of bone ....

History of the disease, examples of it

PAGE

70 70 70 71 71 71

CHAPTER Vn.

NECROSIS.

Definition of necrosis, modes of its occurrence .....

Characters of dead bone ........

Comparative frequency of necrosis in the cancellous and compact tissue of bone

Liability of different bones to necrosis . .....

Peuliar tendency in the head of the tibia to disease ....

Causes of necrosis .........

Removal of periosteum — consequent death of the outer lamellse of the bone

Necrosis of the upper or lower jaw,, how usually arising ....

Necrosis of the lower jaw from scurvy, from excessive salivation .

Necrosis of the jaws in lucifer-match manufacturers ....

Disease in the bones of cows, apparently from the influence of the fumes of arsenic

Necrosis of tuber ischii, trochanter major, from pressure ....

Necrosis of scrofulous bone .......

Necrosis consequent on syphilis .......

Necrosis from rheumatic inflammation of periosteum — examples of it in the trochanter major .........

Consideration of the fistulous passage in the soft parts as a character of necrosis

Symptoms of necrosis ........

Characters of necrosis of the outer lamellse of a bone ....

Characters of necrosis of the inner lamella? of a bone ....

Characters of necrosis of the shaft of a bone in its whole thickness ,

Question of the death of the medullary tissue from necrosis of the walls of a bone

Necrosis near the articular end of a bone — extension of inflammation to the adjacent joint ..........

Mildness of the inflammatory changes in the soft parts around a dead bone, under what circumstances observed .....

History of necrosis in the head of the tibia

Mode of separation of dead from living bone

Analogy of exfoliation to the separation of a slough from soft parts

Phenomena of exfoliation, observed in man and in animals

Analogy of exfoliation to the shedding of the antlers in deer

Pirst investigation of exfoliation as a vital process, by Hunter

Investigation of exfoliation by the microscope

Chemical qualities of the pus from parts adjacent to exfoliating bone

Mode of removal of dead bone .

Disappearance of dead bone without sensible exfoliation, examples of it

Agency of granulations in removing dead bone

Removal of dead bone in particles, by a process designated insensible exfoliation

2*

80 81 82 83 82 83 84

XVU1 CONTENTS,

PAGE

Size of an exfoliated piece of bone in relation to the space in the living bone . 91 Pulsatile movement in the matter adjacent to exfoliating bone . . .91

Extrusion of exfoliated bone, how effected ...... 91

Question of the removal of exfoliated bone by the living parts . . .91

Adhesion of the living parts to dead bone ...... 92

Exfoliation an uncertain process ....... 93

Separative processes consequent on necrosis ..... 93

Question of reproduction of the outer lamella? of a bone . . .94

Phenomena consequent on the death of the outer lamella? of bones in animals

— experiments of Hunter . . . . . . 95

Removal of the entire periosteum of the shaft of a bone in animals — the reparative process . . , . . . , . . . .95

.Activity of the reproductive power possessed by medullary tissue . . 96

Necrosis of the walls of a bone — reproduction by the periosteum . . 96

Necrosis of the inner lamella? of a bone — the reproductive process , . 96

Necrosis of the entire inner lamellae of a bone — separation in the form of a tube 96 Necrosis of the entire thickness and circumference of the shaft of a bone — the reproductive process ........ 97

Reproduction by periosteum considered .".... 97

Question of reproduction by portions of the old bone separated with the periosteum 100 Reproduction from the articular ends of the original bone . . . 101

Question of reproduction by the surrounding soft parts .... 101

Periosteum of the new bone, how formed ...... 102

Holes in the walls of the new bone, how arising, consequences of them . .102

Composition of the new bone ....... 103

Detachment of the articular ends of the original bone before the new bone has acquired firmness, consequences ....... 103

Uncertainty in the time required for reproduction of the shaft of a bone . 104

Cases of necrosis most favourable for the reproductive process . . . 104

Cases of necrosis not followed by any reproductive process . . .105

Necrosis of flat bones — question of their reproduction . . . .105

Necrosis of the ilium — its consequences ...... 105

Question of reproduction of short cylindrical, irregularly-shaped bones . . 106

Instances of necrosis followed by no change in the dead bone and by the closure of the fistulous passage leading to it . . . . . .106

Productions of new bone adherent to dead bone — question of the mode in which this happens . . . . . . . . 107

References to least frequent examples of necrosis . . . . 108

Treatment of necrosis ........ 108

Applications to the soft parts around dead bone . . . . .108

-Applications to the dead bone ....... 109

Superficial necrosis — removal of the dead bone by operation . . .110

Deep-seated necrosis — removal of the dead bone by operation . . .110

Mode of extracting dead bone . . . . . . .110

Treatment of necrosis of the shaft of a bone . . '. . .Ill

Question of the removal of the dead shaft of a bone . . . .113

Necrosis within the head of the tibia — question of the removal of the dead bone 114 Necrosis of the shaft of the tibia — removal of the dead bone . . .114

Necrosis of the humerus — removal of the dead bone . . . .115

Necrosis of the lower part of the femur — removal of the dead bone . • 116

Treatment of necrosis of the bone of a finger or toe . . . . 116

Illustrations of operative proceedings for the removal of dead bone -. . 117

CONTENTS.

XIX

Part II. Tumors Of Bone

Characters of the morbid growths from bone

Arrangement of the tumors of bone ....

Principal products found in the tumours of bone .

Tumour of bone composed chiefly of cartilaginous substance

Two forms of the cartilaginous tumor ....

Characters of the cartilaginous tumor ....

Diagnosis of the cartilaginous tumor ....

Progress of the cartilaginous tumor to a large size, changes in it Influence of remedies upon the cartilaginous tumor Cartilaginous substance combined with other morbid products . Tumor of bone composed chiefly of osseous substance . Exostosis, composition ......

Mode of formation and growth — primordial cartilage

Varieties of exostosis

Distinction between exostosis and enchondroma

Figure — size of exostoses .

Many exostoses in the same individual

Diagnosis of exostosis

Exostosis from the bone of a finger or toe

Consequences of exostoses .

Exostosis from the bone of a toe — its characters, consequences

Treatment of exostosis

Eemoval of exostoses by operation

Mode of removing exostosis from the last bone of a toe

Exostosis from the femur close to the knee-joint, its removal by operation

Bemoval of hard exostoses

Spontaneous separation of exostoses

Suppuration within an exostosis .

Malignant osseous (osteoid) tumor

Characters of the malignant osseous tumor

Instances of the malignant osseous tumor

Tumor of bone composed chiefly of encephaloid substance

Characters and progress of the encephaloid tumor

Diagnosis of the encephaloid tumor

Question of amputating a limb, the seat of the encephaloid tumor of bone

Tumor of bone, composed chiefly of fibrous tissue

Characters of the fibrous tumor ....

Diagnosis of the fibrous tumor ....

Tumor of bone, composed chiefly of gelatinous substance

Characters of the gelatinous tumor

Tumor of bone, composed chiefly of fatty substance

Characters of this tumor ,

Tumor of bone, composed of a soft substance, of the character of erectile tissue

PAGE 125

CONTENTS.

PAGE

Characters of this tumor . . . , . . . .155

Tumor of bone composed chiefly of blood . . . . . 156

Characters and progress of this tumor . . . . . .156

Question of the sanguineous tumor being a variety of encephaloid disease . 157 Tumor of bone consequent on the production of entozoa within it . . 158

Characters and progress of the hydatid tumor of bone . . . .158

Diagnosis of this tumor . . . . . . . .159

Treatment of hydatids in bone ....... 161

Tumor of bone consequent on the formation of membranous cysts within it . 162 Characters of this tumor . . . . . . . 1 62

General considerations relative to the diagnosis and prognosis of the tumors of

Tumors composed of soft substance, yet incompressible . . . .163