THE SHOULDER-JOINT 



223 



it is fixed on the dorsal aspect to the j)roniinent rough surface of the glenoid pro- 

 cess, reaching as far as the neck of the bone. Above, it is attached to the root of 

 the coracoid process: in front, to the ventral surface of the glenoid process, at a 

 variable distance from the articular margin, often reaching half an inch (12 mm.) 

 u{)on the neck of the bone, and thus allowing the formation of a pouch; it may 

 not, however, extend for more than a quarter of an inch (6 mm.) beyond the 

 articular margin: below, it l.)lends with the origin of the long head of the triceps. 

 At the humerus, the up})er half is fixed to the anatomical neck, sending a pro- 

 longation downwards between the two tuberosities which attenuates as it descends, 

 and covers the transverse humeral ligament. The lower half of the capsule 

 descends upon the humerus further from the articular margin, some of the deeper 

 fibres being reflected upwards so as to be attached close to the articular edge, thus 

 forming a kind of fibrous investment for the neck of the humerus. This ligament 

 is more uniform in thickness than that of the hip. 



Gleno-humeral bands of the capsule (figs. 224 and 225). — There are three 



Fig. 224. — Vertical Section through the Shoulder-joint to show the Gleno- 

 humeral LlGAMEXT. 



fhe joint is opeued from behind.) 



Supra-spinatus 

 muscle 



Subacromial bursa 

 Tendon of biceps 

 with gleno-hume- 

 ral ligament 

 Tendon of subsca- 

 pularis 



Capsular ligament 



Suprascapular 

 ligament 



Glenoid ligimeut or flbro-cartilage 



accessory bands which strengthen the capsule, two of which are seen superficially, 

 and consist of a few strengthening fibres, one on the inner aspect reaching from the 

 glenoid cavity to the lower border of the lesser tu))erosity along the lower border of 

 the subscapularis tendon ; and the inferior reaching from the under part of the 

 glenoid cavity to the und(n- part of the neck of the humerus. The third, the superior 

 band, is known as the gleno-humeral ligament, and can only be seen after o])en- 

 ing the capsule. It runs from the edge of the glenoid cavity at the root of the 

 coracoid process, just internal to the origin of the long tendon of the biceps, and, 

 passing inwards and downAvards at an acute angle to the tendon, for which it forms 

 a slight groove or sulcus, is fixed to the lesser tuberosity of the humerus. It is a 

 thin, ribl)on-like ])and, of wliich the up])er surface is attached to the capsule, while 

 the other is free and turned towards tlie joint. In the ftetus it is often, and in tlie 

 adult occasionally, quite frc-e from tlie capsule, and may be as thick as the long 

 tendon of the biceps (fig. 225). 



The tendons of the mpra- and iufra-spinatus, teres minor, and subscapularis 

 muscles strengthen and support the cai)sule, especially near their points of inser- 



