302 



THE ARTICULATIONS, OR JOINTS 



The second, which is not constant, is at the posterior part, where a communica- 

 tion sometimes exists between the joint and a bursal sac belonging to the Infra- 

 spinatus muscle. The third is seen between the two tuberosities, for the passage 

 of the long tendon of the Biceps brachii muscle. It transmits a sac-like prolonga- 

 tion of the synovial membrane, which ends as a blind pouch opposite the surgical 

 neck of the bone. 



The coracohumeral ligament (ligamentum coracohumerale) (Fig. 244) is a broad 

 band which strengthens the upper part of the capsular ligament. It arises from 

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

 outward to the front of the great tuberosity of the humerus, being blended with 

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

 the capsular ligament throughout the greater part of its extent. 



ARTICULAR 

 CAPSULE 



LONG HEAD OF 

 BICEPS MUSCLE 



SUPERIOR 



TRANSVERSE 



LIGAMENT 



SPINE OF SCAPULA 



(sawed off at its origin) 



FIG. 247. Right shoulder-joint, frontal section, from behind. (SpaLteholz.) 



Supplemental Bands of the Capsular Ligament. In addition to the coracohumeral 

 ligament, the capsular ligament is strengthened by supplemental bands in the 

 interior of the joint, and can be best studied by opening the capsule from behind 

 and removing the head of the humerus. One of these bands (Flood's ligament) 

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

 tuberosity of the humerus. It is supposed to correspond with the ligamentum 

 teres of the hip-joint. A second of these bands fSchlemm's ligament), is situated 

 at the lower part of the joint, and passes from the under edge of the glenoid cavity 

 to the under part of the neck of the humerus. A third, called the glenohumeral 

 ligament, is situated at the upper part of the joint. It is attached, above, to the 

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

 downward along the inner edge of the tendon of the Biceps brachii, is attached, 

 below, to the lesser tuberosity of the humerus, where it forms the inner boundary 



