Whatever may be the operation of this cause, that of the other two is by no means so ob vious. The second I has been generally ad duced in explanation of the non-union of fractures of the neck of the thigh-bone, but perhaps without being entitled to the impor tanc,e that has been attached to it. If a part is only possessed of a degree of organisation barely sufficient to preserve its vitality in ordi nary circumstances, but inadequate to accom plish any process of repair, it should follow that any violence offered to it ought to cause its death, or at least its removal by the ab sorbents, and in such case the caries or exfo liation of a fragment of bone might be easily understood. But these are not the results of fracture of the neck of the femur except in very rare and anomalous cases ; and, on the contrary, there is scarcely an example of exami nation after death that did not exhibit a conside rable display of reparative energy, although the results were not such as to produce ossific union. Professor Colles§ has published twelve cases of post-mortem examinations of this accident, in some of which he observed the appearance of ivory-like patches on the surface of the superior fragment, evidently proving the ex istence of considerable ossific powers in this part. Besides, this condition of the head of the bone has been assumed rather than proved. On the most attentive examination, we have not been able to observe any deficiency of vascu larity within it ; and if there is any difference between the head and neck and shaft, we are rather disposed to believe the head to be pos sessed of the highest degree of organization.
The advantage of the most absolute rest to the cure of fracture has been observed in all ages, and yet is it doubtful how far its influence on the question under consideration can be appre ciated. Few fractures can be kept in a more perfect state of repose than those of the patella or of the heel, yet the union in both these cases is always ligamentous. It would appear as if constant although very trifling motion was more prejudicial than occasional shocks however rude and productive of greater dis turbance, and this perhaps is the reason why false joints so frequently occur after fractures of the clavicle, even although the fragments have never suffered displacement, as occurs when the bone is broken near its acromial extremity.
Suppuration may occur in the osseous tissue under a variety of conditions, as to situation, as to the character of the matter, and as to whether it is produced by or connected with any constitutional or specific taint. Pus is occasionally, though not frequently contained in a cyst or sac within a bone, as the result of inflammation, and resembling the common ab scess in the soft parts. These collections are never very large ; they are usually situated in the thick and spongy parts of the bones, and have a strong tendency to burst into the neigh bouring joint. We have seen a case of abscess in the head of the tibia, which appeared to have opened into the knee-joint even after it had burst externally. The disease had pre viously existed for months, the patient suf fering very little either locally or constitutionally until the communication with the cavity of the articulation was established, when the symp toms became so aggravated as to demand the speedy removal of the limb. The symptoms of suppuration within a bone are exceedingly obscure, nor is there any certainty until the abscess has burst and a probe can be passed into the cavity, particularly if the inflammation has not been attended with enlargement of the bone. The pain is said to be agonizing, but
this is not universally true, and we may infer that suppuration has taken place " by the violent symptoms of active inflammation les sening, by cold fits and shivering occurring, by a remission of pain with an increased sense of weight in the part ; but all these are fal lacious, and no external marks of suppuration are at first to be observed, the disease affecting parts too deep to be seen with the eye or felt with the finger." Suppuration on the surface of a bone is of very common occurrence, and so constantly complicated with affections of the periosteum, that it is difficult to say which structure is the source of the purulent secretion; the disease, indeed, is generally described under the name of periostitis. We are disposed, however, to regard it as inflammation of the bone in the first instance, although the membrane comes very soon to be engaged ; because in many cases the pain in the commencement is not ag gravated by external pressure, which it uni formly is when the periosteum is engaged, and also because in very severe cases, such as paronychia periostei, a portion of the hone becomes carious, and is lost even from the earliest period. It is most frequently ob served in connexion with some constitutional taint, such as scrofula or syphilis,* but it may and very often does appear purely as an idio pathic disease. " Inflammation of the pe riosteum, unconnected with any known con stitutional disease, is an affection with which practical surgeons are well acquainted. It is remarkable, however, that a disease so impor tant in its consequences and of such frequent occurrence, should not have been noticed in any systematic work, nor have been made the sub ject of any separate inquiry."1 Whether we consider this affection to belong primarily and principally to the bone or pe riosteum, it is certain that the former structure always is engaged, and shews the most evident marks of activity in the disease, although this, perhaps, may in part be explained by the fibrous texture of the membrane and its defi cient organization. The bone is always in flamed. Even in the most chronic case that leads only to a thickened condition of the pe riosteum, the bone is preternaturally vascular, and so soft that it is often difficult in such cases to distinguish the limits between the sof tened bone and the condensed periosteum.t In the severer forms, the bone, unable to sus tain itself under the excitement, is always dead, and must be gotten rid of by ulceration or exfoliation : in these cases the periosteum is detached, and a fluid, very generally thin, ichorous, and fetid, is interposed between them. Between these extremes there is every possible variety, and, therefore, there will be vast dif ferences in the results of the inflammation, sometimes in the mere thickening of the pe riosteum, sometimes in the deposition of more bony matter, or the apparent ossification of the membrane (exostosis) ; occasionally in the ab sorption of the bone, and most frequently, particularly in specific diseases, in that which is our more immediate object, the deposition of purulent matter.