58 Anatomy Applied to Medicine and Surgery. 



juries to the shoulder joint occur in patients who are 

 under the age of twenty years, since the epiphyseal end of 

 the humerus unites with the shaft about that period. The 

 age of the patient, the softer character of the crepitation, 

 and the presence, in an abnormal position, of the smooth 

 rounded end of the lower fragment in contradistinction to 

 the sharp irregular end of the shaft in fracture of the sur- 

 gical neck of the numerous, assist in differentiating these 

 injuries. In epiphyseal separation the uppet fiagment is 

 drawn up against the acromion and slightly abducted by 

 the supraspinatus muscle, while the subscapularis, having 

 greater leverage than the infraspinatus and teres minor to- 

 gether, rotates it somewhat inwards. The upper end of the 

 lowet fragment is drawn inwards by the pectoralis major, 

 the teres major and the latissimusdorsi muscles. The upper 

 fragment, which is abducted, is so small, that it cannot be 

 brought into line with the lower fragment by means of 

 splints and, hence, Moore advises abduction of the arm in a 

 forward direction so as to bring the lower fragment in ap- 

 position with the abducted upper fragment. In fracture 

 of the sutgical neck the upper fragment would be in much 

 the same position, as it is in epiphyseal separation, while 

 the upper end of the lower fragment would be drawn in- 

 wards by the pectoralis major, tores major and the latissi- 

 mus dorsi; the elbow would be abducted by the deltoid, and 

 the shaft drawn upwards by the deltoid, biceps, triceps 

 and the coraco-brachialis muscles. Inftactwe of the shaft 

 below the insertion of the thoracic muscles and above that 

 of the deltoid, the upper fragment would be drawn inwards 

 by these thoracic muscles, and the lower would be displaced 

 outwards by the deltoid and drawn upwards by the biceps, 

 triceps, etc. When the fracture occurs between the insert- 

 ion of the deltoid and the condyles, the lower end of the 

 upper fragment would be drawn outwards by the deltoid, 



