318 



SYNDESMOLOGY 



evident provision for that extreme freedom of movement which is peculiar to this 

 articulation. It is strengthened, above, by the Supraspinatus ; below, by the long 

 head of the Triceps brachii ; behind, by the tendons of the Inf raspinatus and Teres 

 minor; and in front, by the tendon of the Subscapularis. There are usually three 

 openings in the capsule. One anteriorly, below the coracoid process, establishes 

 a communication between the joint and a bursa beneath the tendon of the Sub- 

 scapularis. The second, which is not constant, is at the posterior part, where an 

 opening sometimes exists between the joint and a bursal sac under the tendon 

 of the Inf raspinatus. The third is between the tubercles of the humerus, for the 

 passage of the long tendon of the Biceps brachii. 



The Coracohumeral Ligament (ligamentum coracohumerale) . This ligament is 

 a broad band which strengthens the upper part of the capsule. It arises from 

 the lateral border of the coracoid process, and passes obliquely downward and 

 lateralward to the front of the greater tubercle of the humerus, blending with the 



Superior transverse Ligament 





Transverse 

 humeral 

 ligament 



Prolongation of 

 synovial mem- 

 brane on tendon 

 of Biceps brachii 



Bursa 



under 



Subscapularis 



FIG. 327. Capsule of shoulder-joint (distended). Anterior aspect. 



tendon of the Supraspinatus. This ligament is intimately united to the capsule 

 by its hinder and lower border; but its anterior and upper border presents a free 

 edge, which overlaps the capsule. 



Glenohumeral Ligaments. In addition to the coracohumeral ligament, three 

 supplemental bands, which are named the glenohumeral ligaments, strengthen 

 the capsule. These may be best seen by opening the capsule at the back of the 

 joint and removing the head of the humerus. One on the medial side of the joint 

 passes from the medial edge of the glenoid cavity to the lower part of the lesser 

 tubercle of the humerus. A second at the lower part of the joint extends from 

 the under edge of the glenoid cavity to the under part of the anatomical neck of 

 the humerus. A third at the upper part of the joint is fixed above to the apex 

 of the glenoid cavity close to the root of the coracoid process, and passing down- 

 ward along the medial edge of the tendon of the Biceps brachii, is attached below 

 to a small depression above the lesser tubercle of the humerus. In addition to 



