T HE problem of recurrent dislocation of the shoulder has troubled orthopedists and surgeons for many years. Numerous theories as to the pathogenesis have been advanced but the following are most commonly accepted. Some authorities, notably Bankhart,’ have described a detachment (usually traumatic) of the glenoid Iabrum from the antero-inferior rim of the glenoid which permits anterior and inferior dislocation of the humeral head. Others (Hill and Sacks) d escribed an abnorma1 groove in the posterolateral quadrant of the humeral head which they believe facilitated recurrent dislocation. Still others, DePalma2 in particular, have found by anatomic studies of a11 ages that the above labral and humeral defects are concomitant with increasing age, but that in the later decades of life, while the bone and labral defects increased in frequency and severity, the incidence of recurrent dislocation declined. From these observations DePalma postulated that other factors must be involved, being convinced that the real causative factor was a tearing and relaxation of the musculotendinous cuff of the shoulder plus a stretching of the other auxiliary stabilizing structures such as the glenohumeral Iigaments and the deltoid muscle. This relaxation permits excessive external rotation of the humeral head which predisposes to dislocation. This postulate is concurred with and appears to account for all the elements necessary to explain this phenomenon. Attempts to correct this disabling condition have been legion. Watson-Jones3 states that sixty different operations have been described. These divide themselves into four classes: tion. This method has not been conspicuously successful. Various suspension operations, such as the Henderson5 and NicolaG procedures, attempting to “snug-up” the humeral head in the glenoid cavity by tendinous slings. These slings passing through bony channels tend to atrophy, become relaxed and finally disintegrate. Bankhart and Putti-Platt believed that by reattaching the glenoid labrum (the typical Bankhartian lesion) or reinforcing the antero-inferior capsule, recurrent dislocations might be prevented. This method has been widely used. In 1945 Magnuson’ proposed an approach to this problem which he believed met all of the factors involved. Recurrent dislocation occurs with the arm in abduction and external rotation. Magnuson believed that by limiting the range of these two types of motion dislocation would be less apt to recur. His method transfers the normal insertion of the subscapularis tendon from the lesser tuberosity to a point distal to the greater tuberosity, thus providing a dynamic musculotendinous sling about the humeral head holding it up, and in internal rotation, preventing dislocation. The author has found this method to be both simple and successful.
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