122 



ELBOW JOINT. 



verse fibres. The internal lateral ligament is in relation posteriorly 

 with the ulnar nerve. 



Fig. 54 * 



Fig. 55.t 



The external lateral ligament is a strong and narrow band, which 

 descends from the external condyle of the humerus, to be inserted 

 into the orbicular ligament, and into the ridge on the ulna, with 

 which the posterior part of the lateral ligament is connected. This 

 ligament is closely united with the tendon of origin of the supinator 

 brevis muscle. 



The synovia!, membrane is extensive, and is reflected from the 

 cartilaginous surfaces of the bones upon the inner surface of the 

 ligaments. It surrounds inferiorly the head of the radius, and 

 forms an articulating sac between it and the lesser sigmoid notch. 



The muscles immediately surrounding, and in contact with, the 

 elbow joint, are in front, the brachialis anticus ; to the inner side, 

 the pronator radii teres, flexor sublimis digitorum, and flexor carpi 

 ulnaris ; externally, the extensor carpi radialis brevior, extensor 



* An internal view of the ligaments of the elbow joint. 1. The anterior ligament 

 2. The internal lateral ligament. 3. The orbicular ligament. 4. The oblique liga- 

 ment. 5. The interosseous ligament. 6. The internal condyle of the humerus, which 

 conceals the posterior ligament. 



tAn external view of the elbow joint. 1. The humerus. 2. The ulna. 3. The 

 radius. 4. The external lateral ligament inserted inferiorly into (5) the orbicular liga- 

 ment. 6. The posterior extremity of the orbicular ligament spreading out at its inser- 

 tion into the ulna. 7. The anterior ligament, scarcely apparent in this view of the 

 articulation. 8. The posterior ligament, thrown into folds by the extension of the joint. 



