Chapter III

. It is a fact, however, that the majority of cases occur in children and after a combination of exposure and fatigue--as, for instance, sitting upon the ice after being exhausted by skating--all of which would be inoperative to produce an infection were not the germs at hand ready to assail every tissue whose resistance is thus temporarily lowered.

The infection may occur _from within_ or _from without_--from within perhaps through the alimentary canal or the respiratory tract, probably from the tonsils and the pharynx. Infection from without may occur through an abrasion or scratch, a blister upon the foot made by an ill-fitting shoe or by a skate-strap. These cases occur generally in the young, more often in boys than in girls, probably because in the former more opportunities for infection are permitted. Bone infections, however, are possible even in the _newborn_, in which case the infection may occur through the pharynx or through the umbilicus, while the local resistance may have been lowered by the injury due to mechanical delivery, turning, etc. In elderly people the disease is almost unknown.

=Diagnosis.=--The disease for which this is most commonly mistaken is acute rheumatism. There may have been some excuse for this in the past because of the lack of general knowledge of bone infections; now there is none. The majority of cases of necrosis following osteomyelitis which have come under the writer’s observation were the result of errors in diagnosis.

Rheumatism is _never followed by suppuration_ and seldom produces a septic type of disease; its painful lesions are rarely so painful as those due to osteomyelitis. Lesions of rheumatism are usually multiple; those of bone infection are mostly single. The first complaint of pain in the latter is generally along the shaft of a bone than at the joint end, while this is not true of rheumatism. Moreover in acute osteomyelitis the disease assumes from the outset a seriousness which is seldom approximated by acute inflammatory rheumatism.

=Treatment.=--The treatment for acute osteomyelitis is essentially surgical. Anodynes may be necessary for relief of pain, but no time should be lost, when once the diagnosis is made, in making _incisions_ to expose the bone involved, and then opening to its interior to relieve tension and to remove septic products. The incision over the femur or tibia, for instance, may be ten or twelve inches in length. The tissues will invariably be found edematous or infiltrated, with evidence of the proximity of pus; the periosteum will be thickened and infected, and between it and the bone, as well as outside of it, there may be collections of pus. If seen late the characteristic muscle appearances already described may be noted. The periosteum should be incised to the bone throughout the length of the incision, and then an ordinary bone drill may be used to perforate the bone for exploratory purposes. From the punctures in the bone thus involved will exude purulent fluid, often sanious, thus indicating the condition within. A deep groove or channel should now be cut, opening into the marrow cavity, in which numerous foci will be found, or in which all distinctive structure of bone-marrow may be lost, the cavity being filled with pus. The pus cavity should be scraped and disinfected with hydrogen peroxide and cauterized with zinc chloride or its equivalent, and then packed, the wound being left open. Even this may not be sufficient, but if there be epiphyseal separation, or evidences of joint infection, the neighboring joints should be explored under aseptic precautions; if pus be found they should be opened, washed out, and drained. Meanwhile if in the soft tissues exposed by the incision the parosteal veins are found filled with septic thrombi, they should be opened as far as exposed and their contents removed.

These operations are often severe, but nothing in the way of operative treatment can be so severe nor so serious as the disease itself when left unoperated; the rule is stringent that every infected tissue, and especially every infected bone interior, should be exposed and cleaned out. Only in this way can lives be saved. Moreover, it is necessary to carry out this treatment in the fulminant cases _as early as possible_; and errors in diagnosis by which it may be postponed until metastatic infection or grave pulmonary and cardiac complications have set in are unfortunate. So long as the local indications are as above described, surgical treatment is desirable, whether the systemic complications are pronounced or not. The immediate effect of the operation having passed the relief thus afforded will often be so pronounced that within twenty-four hours patients may be out of danger.

[Illustration: FIG. 225

Total necrosis of humerus, as seen by aid of the cathode rays. (Lexer.)]

The results of this operation are a wound which will discharge at first freely, and which so soon as septic material is out of the way will begin to _granulate_. Ordinarily no attempt should be made to close such a wound, though much may be done to favor rapidity of granulation. While some antiseptic dressing is always employed, it will be of advantage occasionally to change the character of the same, and to alternate between various antiseptics, the effect of any one drug being apparently lost after it has been used for some time.

There are some cases where an entire diaphysis or bone shaft will be found separated from one or both epiphyseal terminations, lying in a subperiosteal abscess cavity, bathed in pus, and dead beyond possibility of repair. This is _total necrosis of the shaft_ from an acute infectious process, and is to be treated by complete removal of all dead and dying tissue. In the case of the forearm or leg it may be that the remaining bone, when only one is involved, as is usual, will be sufficient to maintain the integrity of the limb until new bone can be reproduced within the periosteal bed occupied by the old one. More or less complete _regeneration of bone_ is possible, particularly in the young, and in connection with compensatory hypertrophy of the parallel bone will permit the restoration of the leg to partial or complete usefulness. On the other hand, should this later prove a complete failure, amputation and substitution of an artificial limb may be required.

When the disease has involved the articular side of an epiphyseal line, and when there is complete epiphyseal separation with consequent _pyarthrosis_, the probable consequence will be necessity for a complete or partial resection of the joint and the probability of subsequent ankylosis. Patients may find later that a modern artificial limb with its possibilities will be preferable to such a condition, and may readily consent later to an amputation which they would at first refuse.

=Acute Infectious Periostitis.=--This is an infection of the same general character and type as the osteomyelitis just described, but refers to those cases where the disease apparently is confined to the periosteum and the outermost layer of the bone. In its possibilities for harm it is scarcely less serious, although in its tendency to spontaneous perforation and escape of pus it is less likely to prove fatal.

=Causes.=--The causes and the general clinical manifestations are practically identical. The disease is perhaps less grave in its acute manifestations, the localization of pain more exact, with ordinarily less tendency to joint complications. Local tenderness is exquisite, and particularly in those bones which lie near the surface--_e. g._, the tibia--and early recognition of fluctuating areas is easy. It may be localized over a small area, or the entire periosteum of the shaft may be involved; in which case, so soon as pus forms and the periosteum is separated from the bone, there is probability of acute necrosis of the shaft. Here, again, there may be a tendency to mistake at least the first signs of the disease for acute rheumatism, from which it must necessarily be early differentiated as above.

=Treatment.=--Here also there is the same necessity for immediate intervention, if possible before pus be formed, in order that there may be little or no periosteal separation and encouragement to necrosis. Anesthesia is necessary, with prompt incision, the use of the sharp spoon, and disinfecting agents: no attempt should be made to close the wound, but drainage should be favored in every way. The intensity of the pain is promptly relieved and the whole clinical picture immediately changed by such a procedure.

The ordinary _bone felon_ upon a terminal phalanx is practically an expression of this type of disease, and experience corroborates the wisdom of deep and early incision, even in the case of so small a bone entity as a phalanx.

=Acute Epiphysitis.=--This is a term applied rather indiscriminately to a form of acute osteomyelitis involving primarily and especially the epiphyseal lines, or to a condition of hyperemia and neurovascular excitement at epiphyseal junctions stopping short of suppuration, but giving rise to intense pain, muscle contraction, joint tenderness, etc. It is often seen at the upper end of the tibia. Sympathetic disturbance may extend even to serous effusion into a joint, although this is not necessarily the case. The limbs are early drawn up, and every attempt to extend them simply aggravates the distress. So long as there are no evidences of suppuration, it is sufficient in these cases to apply a sufficient degree of traction to overcome muscular contracture and to straighten the limbs. This should be applied first under anesthesia, and the patient kept under anodynes for a few hours thereafter. So soon, however, as the muscles are tired out by the steady traction, pain subsides, and the intensity of the condition may be thus relieved within forty-eight hours or less. It would be well to continue physiological rest and traction as long as there remains the slightest tenderness. Should evidences of suppuration at any time supervene, incision and evacuation of pus and exudate should be practised. Should epiphysitis occur in one of two parallel bones, there may result such failure of growth of that bone as shall cause marked deformity in the attacked hand or foot. In some of these cases, should operation be required on one bone, the other may be shortened at the time, or later, by exsection of a portion of the shaft, or even of the epiphyseal junction.

[Illustration: FIG. 226

Osteogenesis and osteosclerosis in slow infective processes. (Buffalo Museum.)]

=Periostitis Albuminosa.=--This is a rare manifestation of bone disease, only given an identity of its own since 1868, when Ollier first distinguished it, since which time it has been the subject of considerable controversy. The name refers to a condition less acute than the infectious periostitis just described, almost always localized in a single bone, necessitating incision and evacuation of a fluid which is _gelatinous_ or _mucoid_ in appearance rather than purulent. It is because of the peculiarity of the subperiosteal collection of fluid that it received the name _periostitis albuminosa_, and it was not generally regarded until recently as a variety of the infectious form of periostitis. It is, however, now conceded as being a mitigated form of infection, in which the products of exudation assume the serous rather than the purulent type. In some instances it appears to be the tubercle bacilli which are at fault. At all events, the organisms which produce the disease are more or less virulent, else the clinical form of the disease would be less serious than it really is. Cultures made from these subperiosteal collections have in almost all recent instances revealed the presence of some one of the numerous pyogenic organisms. Quite recently Dor has described a polymorphic microbe, in instances of this kind, which he has called the _Bacillus cereus citreus_, with which he claims to have been able to reproduce the disease in animals.

=Chronic and Latent Osteomyelitis.=--As in the lungs, however, chronic lesions are met with, and as in the lungs, again, it is possible for collections of microörganisms to become more or less encapsulated and for a long time to lie _latent_ until some provoking cause excites them again into activity. In this way are to be explained the numerous instances of recurring abscesses within the bone necessitating repeated operations, often at long intervals. (See Plate XXXVI.)

=Possible Consequences of Any and All of the Bone Infections.=--Bone is a living tissue, calcified and stiffened by inorganic material for the purpose of giving it strength; it may suffer remotely from the consequences of local infections, the same as other tissue. Thus it may have its nutrition impaired so as to produce _atrophy_ on one hand, or increased so as to lead on the other to _hypertrophy_, either regular or irregular in outline. Again in its texture it may be altered to a wide extent between the sponginess or porosity on one side (_osteoporosis_), or to the density attained by ivory (_osteosclerosis_) on the other. Similar changes are also noted in cases of bone tuberculosis, which is to be considered by itself. The _densest_ bone has sufficient vitality to permit its nutrition and life, and may assume dimensions much larger than that of the original, and a hardness which will defy the best steel instruments should it become necessary to operate upon it. The other extreme of _osteoporosis_ includes a condition where the bone has barely sufficient inorganic material to permit it to retain its shape and ordinary proportions. Such bone is fragile in the extreme and scarcely serviceable as a supporting tissue. The principal portion of its bulk is constituted by marrow tissue, which makes it extremely vascular, but far from strong. When spongy it is ordinarily unserviceable for its proper function. Astonishing pictures of _osteosclerosis and osteoporosis side by side_ are present in many instances of disease, the latter being often evidence of more or less ossification of new-formed granulation tissue. This is often a happy combination, because the bone, which has been sadly weakened by disappearance of its calcareous material by liquefaction and by absorption, is reinforced along some of its lines by a pillar of osteosclerotic tissue, by means of which it still functionates as a more or less useful support (Fig. 226).

The operating surgeon should familiarize himself with the density of normal bone in various locations, as in many operations upon the deeper bones he detects healthy bone rather by the sense of _touch_ and of _hearing_, and the _resistance_ which it offers to his instruments, than by sense of sight.

TUBERCULOSIS OF BONE.

In