196 



THE ARTICULATIONS. 



continuous, behind, with the arcif orm ligamentous bands which stretch from the 

 ubia to the radius. Its deep fibres are shghtly obUque downwards and forwards. 

 b. The lateral internal ligament — also funicular — is longer, but not so strong 



as the preceding. It arises from 

 Fig. 128. the small tuberosity on the inner 



side of the superior articular face 

 of the humerus, and, widening as 

 it descends, reaches the radius. Its 

 median fibres, which are the longest, 

 are directed vertically downwards 

 to reach the imprints situated below 

 the bicipital tuberosity ; its anterior 

 fibres, curved forwards, are united 

 to the tendon of the coraco-radialis 

 muscle, or are confounded ^^■ith the 

 anterior ligament ; the posterior are 

 turned backwards, near their in- 

 ferior extremities, to join the arci- 

 form fibrous fascicuU, which in- 

 wardly unite the ulna to the radius. 

 The middle fibres of this Ugament 

 cover the inferior insertion of the 

 short flexor of the forearm, and — in 

 part only — that of the long flexor. 

 It is covered by the ulna-plantar 

 nerve and the posterior radial artery 

 and vein. 



c. The anteiior or capsular liga- 

 ment (Figs. 128, 9) is a membrani- 

 form band, attached by its superior 

 border above the humeral articular 

 surface, and by its inferior to the 

 anterior margin of the radial sur- 

 face. By its lateral borders, it is 

 confounded with the funicular Uga- 

 ments. Its internal half is formed 

 of vertical fibres which descend from 

 the humerus and expand over the 

 radius, where they become united 

 with the inferior tendon of the 

 coraco-radialis muscle. In its exter- 

 nal moiety it is extremely thin, and 

 composed of fibres crossed in various 

 directions. Lined internally by 

 synovial membrane, this ligament is 

 in contact, by its external surface, 

 with the anterior radial vessels and 

 nerves, the two flexor muscles of 

 the forearm, the anterior extensor of 

 the metacarpus, and the anterior extensor of the phalanges. The two latter muscles 



6capul0-humeral and humero-radial articula- 

 tions, with the muscles surrounding them 

 (external face). 



1, Scapulo-humeral capsular ligament ; 2, short ab- 

 ductor muscle of the arm ; 3, its insertion in the 

 humerus; 4, insertion of the infra-spinatus muscle 

 on the crest of the great tuberosity; 5, coraco-radialis 

 muscle; tj, its tendon of origin ;ittached to the 

 coracoid process; 7, its radial insertion confounded 

 with the anterior ligament of the ulnar articula- 

 tion ; 8, 8, external lateral ligament of that articu- 

 lation ; 9, anterior ligament ; 10. aconeus, or small 

 extensor of the forearm ; 11, origin of the external 

 flexor muscle of the metacarpus; 12, short flexor 

 muscle of the forearm. A, Tuberosity of the scapii- 

 lar spine; B, supra-spinous fossa; C, infra-spinous 

 fossa : D, convexity of the small trochanter ; E, 

 summit of the ti-ochanter. 



