352 Surgical Diseases and Surgery of the Dog 



A luxation may be partial or complete, according to the degree 

 of displacement present. Complete luxations are seen mostly in 

 enarthrodial joints such as the femoro-coccygeal, but they are also 

 very frequently partial in such joints. Partial luxations commonly 

 occur in the digits. This lesion generally carries with it more or less 

 bruising of the articular cartilages, rupture of ligaments, and con- 

 tusion of the neighboring parts. 



Symptoms and Diagnosis. The symptoms are : pain, deformity, 

 either lengthening or shortening of the affected member, and immo- 

 bility. In general, a luxation may be differentiated from a fracture 

 by the absence of crepitus, but this is not invariably a guide since 

 the synovia may become inspissated and crackle under motion. The 

 chief distinguishing feature is the abnormal immobility, though 

 movements are sometimes possible in certain directions, while in 

 fracture there is abnormal mobility in all directions. The diagnosis 

 may be rendered difficult by the presence of tumefaction sufficient 

 to prevent the exact extent of the injury from being ascertained. 



Treatment. The sooner a reduction is effected the greater are 

 the chances of repair and restoration of function in the joint. If a 

 luxation is allowed to remain undisturbed for a longer period than 

 two or three weeks a change takes place in the relation of the parts. 

 The head of the displaced bone becomes enveloped in a new cap- 

 sular ligament formed from the surrounding cellular tissue, and 

 reduction is no longer possible. While the displaced bone gradually 

 adapts itself to its abnormal environment, so that a certain degree 

 of motion becomes possible, lameness invariably remains perma- 

 nently. 



A case of luxation being presented, the first step is to secure 

 the animal, place it in a convenient position and proceed to examine 

 the seat of injury. If much swelling is present, the operation should 

 be postponed until it has subsided. Subsidence of the swelling may 

 be aided by playing a stream of cold water from a hose over the 

 parts, or by applying a refrigerant lotion. Recourse to general 

 anesthetics or preferably chloretone narcosis is of considerable as- 

 sistance and in some cases absolutely essential in order to overcome 

 muscular spasm. The parts are then manipulated with the aim to 

 restore the normal contiguity of the articular surfaces. Traction 

 is exerted on the member, sufficient to overcome muscular effort, 

 and then either extension, flexion, lateral pressure, or rotatory move- 



