ARTICULATIONS. 



preceding; and above to the trapezoid ridge on the under sur- 

 face of the clavicle. A bursa usually lies in the re-entrant 

 angle of junction of these two parts. [274] 



Ligaments of the Scapula. The coraco-acromial is a tri- 

 angular band attached by its base to the postero-external bor- 

 der of the coracoid process, and by its apex to the tip of the 

 acromion process just external to the acromio-clavicular joint. 

 The suprascapular is a short, flat band bridging the suprascap- 

 ular notch; a small duplicate may bridge the foramen ven- 

 trally. The spino-glenoid consists of fibres running from the 

 external border of the spine to the back of the head. [275] 



Shoulder Joint. This is an enarthrodial diarthrosis be- 

 tween the head of the humerus and the glenoid fossa of the 

 scapula. The glenoid ligament, lying within the capsule, is a 

 strong ring of dense fibrous tissue, which is attached to the free 

 margin of the glenoid fossa along its broad outer edge, or base; 

 its inner edge is free and thin; the long tendon of the Biceps 

 partly fuses with it at the apex of the fossa. [276] 



The capsule is attached above to the circumference of the 

 fossa, external to the glenoid ligament, and also to the liga- 

 ment; and below to the neck of the humerus. It is strongest 

 above; the fibres are partly circular but mainly longitudinal. 

 A prolongation (transverse humeral ligament) bridges the part 

 of the bicipital groove between the tuberosities of the hu- 

 merus; it leaves an opening for the long tendon of the Biceps, 

 which runs within the capsule, above the head and neck of the 

 humerus. There is usually another opening in its upper and 

 front part under the Subscapularis tendon, where a protrusion 

 of the sy no vial membrane forms a bursa; there may be an 

 opening under the Infraspinous tendon; through these open- 

 ings the joint communicates with the bursae under these 

 tendons. The tendons of the Subscapularis, Supraspinatus, 

 and Infraspinatus fuse with the upper part of the capsule. 

 On the inner aspect of the anterior part of the capsule are 

 seen three thick bands (gleno-humeral ligaments), which are 



[151] 



