198 



THE SUPERIOR EXTREMITY 



The nerve supply of the joint is derived from the median, 

 ulnar, and radial nerves. 



Movements at the Elbow Joint. The movements at the elbow joint 

 must not be confounded with those that take place at the proximal radio- 

 ulnar joint. At the elbow joint two movements, viz. , fexion, or forward 

 movement of the forearm, and extension, or backward movement of the 

 forearm, are permitted. 



The muscles which are chiefly concerned in flexing the forearm upon the 



Anterior 

 part of capsule 



Lig. collaterale 

 radiale 



Lig. annulare 



Radius 



Epicondylus 

 medialis 



Lig. collaterale 

 u In are 



Tendon of biceps hrachii 



Chorda obliqua 

 Ulna 



FIG. 85. Anterior aspect of the Elbow Joint. 



arm at the elbow joint are the biceps, the brachialis, the muscles attached 

 to the medial epicondyle, and the brachio-radialis. The muscles which 

 extend the forearm are the triceps and anconseus and the muscles which 

 spring from the lateral epicondyle. 



Dissection. It is advisable to study the radio-carpal or wrist 

 joint, before the articulations between the two bones of the 

 forearm are examined. The transverse, volar, and dorsal carpal 

 ligaments, together with the extensor and flexor tendons, should 

 be completely removed from the wrist. No attempt, however, 

 should be made to detach the extensor tendons from the dorsal 

 aspects of the fingers and thumb. The short muscles of the 

 thenar and hypothenar eminences must also be taken away. 



