Wounds.

Wounds which cause a break of the skin and fascia overlying the scapulohumeral joint are usually of little consequence, unless the blow is of sufficient force to directly injure the articulation, and in such cases, the treatment of the injury along general surgical principles, such as cleansing the area, providing drainage for wound secretion, and the administration of suitable dressing materials such as antiseptic dusting powder, is all that is required for the wound.  The symptoms manifested by the subject in such cases are the same as have been discussed heretofore and merit no special consideration.

Prognosis.—­Unless very serious injury be done the articular portions of the scapula or the humerus, resulting in the destruction of the capsular ligament, prognosis is entirely favorable.

Open Joint.—­Where the capsular ligament is perforated and the condition becomes one of open joint, then a special wound treatment becomes necessary.  The surface of the skin is first freed from all hair and filth in the vicinity of the wound.  The wound proper is cleared of all foreign material either by clipping with the scissors, curetting or mopping with cotton or gauze pledgets.  The whole exposed wound surface as well as the interior of the joint cavity, if much exposed, is moistened with tincture of iodin.  Subsequent treatment consists in a local application of a desiccant dusting powder, which should be applied five or six times daily.  The composition of the powder should be such as to permit of its liberal use, thereby affording mechanical protection to the wound as well as exerting a desiccative effect.  Equal parts of boric acid and exsiccated alum serve very well in such cases.

Animals suffering from open joints of this kind should be confined in a standing position, preferably in slings, and kept so confined for three or four weeks.  Since they usually bear weight upon the affected member, there is no danger of laminitis resulting.

Luxation of the Scapulohumeral Joint.

Because of the large humeral head articulating as it does with a glenoid cavity, scapulohumeral luxations are very rare in the horse.  According to Moller[7], luxation is generally due to excessive flexion of the scapulohumeral joint.  In such cases the head of the humerus is displaced anterior to the articular portion of the scapula and remains so fixed.

Symptoms.—­Complete luxation of the scapula is recognized because of immobility of the scapulohumeral joint and of the abnormal position of the head of the humerus, which can be recognized by palpation, unless the swelling be excessive.  Immobility of the scapulohumeral joint is noticeable when one attempts to passively move the parts.

Treatment.—­Reduction of the luxation is effected by making use of the same general principles that are employed in the reduction of all luxations, and they are—­the control of the animal so that the manipulations of the operator are not antagonized by muscular contraction, which is best accomplished by anesthesia; placing the luxated bones in the position which they have taken to become unjointed; and then making use of force which is directed in a manner opposite to that which has effected the luxation.