400 



SURGICAL ANATOMY. 



249. Fracture of the Humerus 

 above the Condyles. 



elbow approximated to the side, and retained there by a broad roller passed round the chest ; the 

 forearm should then be flexed, and the hand supported in a sling, care being taken not to raise 

 the elbow, otherwise the lower fragment may be displaced upwards. 



In fracture of the shaft of the humerus below the insertion of the Pectoralis Major, Latissimus 

 Dorsi, and Teres Major, and above the insertion of the Deltoid, there is also considerable deformity, 

 the upper fragment being drawn inwards by the first-mentioned muscles, and the lower fragment 

 upwards and outwards by the Deltoid, producing shortening of the limb, and a considerable 

 prominence at the seat of fracture, from the fractured ends of the bone riding over one another, 

 especially if the fracture takes place in an oblique direction. The fragments may be brought 

 into apposition by extension from the elbow, and retained in that position by adopting the same 

 means as in the preceding injury. 



In fracture of the shaft of the humerus immediately below the insertion of the Deltoid, the 

 amount of deformity depends greatly upon the direction of the fracture. If the fracture occurs 

 in a transverse direction, only slight displacement occurs, the upper fragment being drawn a 

 little forwards ; but in oblique fracture, the combined actions of the Biceps and Brachialis Anti- 

 cus muscles in front, and the Triceps behind, draw upwards the lower fragment, causing it to 

 glide over the upper fragment, either backwards or forwards, according to the direction of the 

 fracture. Simple extension reduces the deformity, and the 

 application of splints on the four sides of the arm will 

 retain the fragments in apposition. Care should be taken 

 not to raise the elbow ; but the forearm and hand may be 

 supported in a sling. 



Fracture of the humerus (Fig. 249) immediately above 

 the condyles deserves very attentive consideration, as the 

 general appearances correspond somewhat with those pro- 

 duced by separation of the epiphysis of the humerus, and 

 with those of dislocation of the radius and ulna backwards. 

 If the direction of the fracture is oblique from above, 

 downwards, and forwards, the lower fragment is drawn 

 upwards and backwards by the Brachialis Anticus and 

 Biceps in front, and the Triceps behind. This injury may 

 be diagnosed from dislocation, by the increased mobility in 

 fracture, the existence of crepitus, and the fact of the 

 deformity being remedied by extension, on the discontinu- 

 ance of which it is reproduced. The age of the patient is 

 of importance in distinguishing this form of injury from 

 separation of the epiphysis. If fracture occurs in the op- 

 posite direction to that shown in the accompanying figure, 

 the lower fragment is drawn upwards and forwards, causing 

 a considerable prominence in front ; and the upper fragment 

 projects backwards beneath the tendon of the Triceps 

 muscle. 



Fracture of the coronoid process of the ulna is an ac- 

 cident of rare occurrence, and is usually caused by violent 



action of the Brachialis Anticus muscle. The amount of displacement varies according to the 

 extent of the fracture. If the tip of the process only is broken off, the fragment is drawn up- 

 wards by the Brachialis Anticus on a level 

 with the coronoid depression of the humerus, 

 and the power of flexion is partially lost. If 

 the process is broken off near its root, the 

 fragment is still displaced by the same muscle ; 

 at the same time, on extending the forearm, 

 partial dislocation backwards of the ulna 

 occurs from the action of the Triceps muscle. 

 The appropriate treatment would be to relax 

 the Brachialis Anticus by flexing the forearm, 

 and to retain the fragments in apposition by 

 keeping the arm in this position. Union is 

 generally ligamentous. 



Fracture of the olecranon process (Fig. 250) 

 is a more frequent accident, and is caused 

 either by violent action of the Triceps muscle, 

 or by a fall or blow upon the point of the 

 elbow. The detached fragment is displaced 

 upwards, by the action of the Triceps muscle, 

 from half an inch to two inches ; the promi- 

 nence of the elbow is consequently lost, and a 

 deep hollow is felt at the back part of the 

 joint, which is much increased on flexing the limb. The patient at the same time loses, more or 

 less, the power of extending the forearm. The treatment consists in relaxing the Triceps by 

 extending the limb, and retaining it in the extended position by means of a long straight splint 



250. Fracture of the Olecranon. 



