THE FRONT OF THE ARM in 



Other structures which are under cover of the boundaries 

 but are not strictly within the fossa are : the termination 

 of the radial nerve and parts of its deep and superficial 

 divisions; the anterior terminal branch of the profunda 

 artery; the radial recurrent artery; the volar and dorsal 

 ulnar recurrent arteries and twigs of the superior and inferior 

 ulnar collateral arteries. 



Dissection. The fascial roof of the cubital fossa was partially 

 destroyed when the deep fascia of the front of the arm was 

 reflected, but the lacertus fibrosus is still in position. Now 

 cut across the lacertus near the biceps (Fig. 47), and reflect it 

 towards the medial border of the forearm, then proceed to clean 

 the contents of the fossa. Pull aside the medial and lateral 

 boundaries with hooks and then commence with the median 

 nerve. Follow it from above downwards to the point where it 

 disappears between the two heads of the pronator teres, and 

 secure the branches which spring from its medial side and pass 

 to the muscles which arise from the medial epicondyle of the 

 humerus. 



Next clean the brachial artery, also from above downwards. 

 If its venae comites are in the way remove them. Follow the 

 artery to its division into its radial and ulnar branches, then 

 follow the radial artery to the apex of the fossa, and the ulnar 

 artery to the point where it disappears behind the deep head of 

 the pronator teres. Do not injure the radial recurrent branch 

 which springs from the lateral side of the radial artery, or the 

 volar and dorsal ulnar recurrent branches which arise from the 

 medial side of the ulnar artery. Now clean the tendon of the 

 biceps brachii and follow it to its insertion into the posterior part 

 of the tuberosity of the radius, and note that, as it passes to its 

 insertion, it twists so that its anterior surface becomes lateral, 

 and its posterior surface becomes medial. The tendon is 

 separated from the anterior part of the tuberosity by a small 

 bursa which may be opened with the point of the scalpel. 



To facilitate the cleaning of the floor and to expose structures 

 which are not strictly contents of the fossa, but which lie close 

 to it, under cover of its medial and lateral boundaries, flex the 

 elbow slightly, and pull the medial and lateral boundaries of the 

 fossa still wider apart. Find the termination of the radial nerve, 

 and the anterior terminal branch of the profunda artery at the 

 level of the lateral epicondyle between the brachio-radialis and 

 the brachialis. Follow the deep and superficial terminal branches 

 of the nerve, downwards in front of the lateral part of the 

 capsule of the elbow- joint. The deep branch disappears into the 

 substance of the supinator. The superficial division descends 

 between the brachio-radialis and the supinator, either superficial 

 or deep to the branches of the radial recurrent artery. The 

 termination of the superficial division has already been dissected 

 on the dorsum of the hand where it supplies the lateral three- 

 and-a-half digits (see p. 71). Next follow the radial recurrent 

 artery to the lateral epicondyle, where it anastomoses with the 

 anterior terminal branch of the profunda artery. Then trace 

 the volar and dorsal recurrent branches of the ulnar artery to 



