THE UPPER EXTREMITY. 



69 



Brachialis anticus, 325; Fig. 270. (326-7) 



Origin. Insertion. Structure. Nerve-supply. Action. Relations. Variations. 



Remove the deep fascia from the posterior surface of the arm and expose the triceps. Trace the mus- 

 culo spiral nerve and the superior profunda artery. 



Triceps extensor cubiti, 326-7 ; Fig. 268. (327-8-9) 



Origin, long head, external head, internal head. Insertion. 

 Structure. Nerve-supply. Action. Relations. Variations. 

 Musculo-spiral nerve, 841. (821-2) 



Branches : Internal cutaneous branch. 



External cutaneous branches : 



Upper branch. Lower branch. 



Nerve to the long head. Nerves to the outer and inner heads. 

 Nerve to the anconeus. 

 Nerves to the brachialis anticus, supinator longus and extensor carpi 



radialis longior. 

 Superior profunda artery, 562. (551-2) 



Branches: Ascending branch. Cutaneous branch. Articular branch. 

 Nutrient artery. Muscular branches. 



Chief variations. 



Forearm. 



Remove the skin and superficial fascia to the wrist. 



Deep fascia, 327-8. (329) 

 Anterior annular ligament. 



The deep fascia of the lower portion of the forearm, above the annular ligament, should be carefully 

 reflected from the surface of the muscles. Care must be exercised not to remove the cutaneous nerve 

 branches which pierce the deep fascia near the wrist and pass for distribution to the palmar and dorsal 

 suriaces of the hand. At the upper part of the forearm near the internal condyle, the deep surface of 

 the fascia gives origin to muscles and cannot be removed without injury to the muscles. The muscles 

 should be carefully exposed and separated and the vessels and nerves displayed. 



Brachio-radialis or supinator radii longus, 339 ; Fig. 272. (340) 



Origin. Insertion. Structure. Nerve-supply. Action. Relations. Variations. 



That part of the brachio-radialis in relation with the radial artery should be raised and pushed aside to 

 expose the vessel. The muscle will be considered later. 



The radial artery, 571 ; Fig. 355. (561) 



The radial artery in the forearm, 571-2. (562-3) 



Relations: In front. Behind. Outer side. Inner side. 



Variations in the radial artery in the forearm, 572-3. (563) 



Branches of the radial artery in the forearm, 573-4. (563) 



Radial recurrent. Muscular branches of the radial artery. 

 Anterior radial carpal. Superficial volar. 

 Radial vein accompanies the artery. 

 Radial nerve, 841-2. (823) 

 Pronator radii teres, 328-9-30 ; Fig. 272. (330-1) 



Origin. Insertion. Structure. Nerve-supply. Action. 

 Flexor carpi radialis, 330-1 ; Fig. 272. (832) 



Origin. Insertion. Structure. Nerve-supply. Action. Relations. Variations. 

 Palmaris longus, 331 ; Fig. 272. (332) 



Origin. Insertion. Structure. Nerve-supply. Action. Relations. Variations. 

 Flexor carpi ulnaris, 321-2; Fig. 272. (333) 



Origin. Insertion. Structure. Nerve-supply. Action. Relations. Variations. 

 Flexor sublimis digitorum, 332-3-4-5 ; Fig. 273. 



Origin. (Insertion.) Structure. Nerve-supply. 

 The ulnar artery, 563-4. (553) 



Relations of the ulnar artery in the forearm, 564-5. (553-4) 

 In front. Behind. Outer side. Inner side. 



Variations of the ulnar artery in the forearm. (555) 



Relations. Variations. 



(334-5-6) 

 Action. Relations. 



Variations. 



