THE FOREARM AND WRIST 65 



J -shaped incision is probably the best, since it is planned so as 

 to do least damage and yet gives good preliminary exposure. 

 Proximally, the incision lies immediately behind the lateral 

 intermuscular septum and the radial collateral (external lateral) 

 ligament, and, below, it follows the distal border of the anconseus 

 to the ulna. The annular ligament is cut through on its lateral 

 aspect and the joint is opened. 



If the subperiosteal method of resection is adopted, large 

 portions of the removed shafts will be reproduced. Some 

 shortening of the limb may follow, but growth is most active 

 and most prolonged at the shoulder and wrist, and consequently, 

 the results of removal of the epiphyses at the elbow are not so 

 serious as might be expected. The flap, which consists of the 

 skin, fascia, triceps, and anconseus, is elevated subperiosteally 

 from the humerus and the ulna until the ulnar collateral liga- 

 ment is freed. After the radial collateral ligament has been 

 dealt with similarly, the olecranon is removed. In this way 

 the joint is widely exposed. In dealing with the neck of the 

 radius, care must be taken lest the deep branch of the radial 

 nerve (posterior interosseous nerve) should be injured in its 

 passage through the supinator (s. brevis), and the dependent 

 pouch of the synovial membrane in this situation (Fig. 17) 

 must be totally extirpated. The synovial membrane covering 

 the fatty pads (p. 54 ) which fill up the humeral fossae is also 

 completely removed. In this operation the ulnar nerve is not 

 exposed, if the subperiosteal excision is employed. 



THE FOREARM AND WRIST. 



Bony Landmarks. The proximal part of the shaft of the 

 Radius is surrounded by muscles, but the distal part of its 

 lateral surface and most of its distal extremity can be 

 readily examined. The anterior border of its distal end 

 can be made out as a distinct ridge on the front of the forearm 

 about an inch from the thenar eminence. In the hollow 

 immediately proximal to this ridge the radial artery can be 

 felt pulsating, and it may be compressed backwards against 

 the bone. The radial ridge can be traced laterally till it joins 

 the sharp volar (anterior) margin of the bone. When the 



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