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ARTICULATIONS. 



Fig. 132. Left Elbow-Joint, showing Ante- 

 rior and Internal Lateral Ligaments. 



The articular surfaces are covered with a thin layer of cartilage, and connected 

 together bj the following ligaments : 



Anterior Ligament. Internal Lateral. 



Posterior Ligament. External Lateral. 



The Anterior Ligament (fig. 132) is a broad and thin fibrous layer, which covers 

 the anterior surface of the joint. It is attached to the front of the humerus 



immediately above the coronoid fossa; 

 below, to the anterior surface of the 

 coronoid process of the ulna and orbicu- 

 lar ligament, being continuous on each 

 side with the lateral ligaments. Its super- 

 ficial or oblique fibres pass from the inner 

 condyle of the humerus outwards to the 

 orbicular ligament. The middle fibres, 

 vertical in direction, pass from the upper 

 part of the coronoid depression, and 

 become blended with the preceding. A 

 third, or transverse set, intersect these at 

 right angles. This ligament is in relation, 

 in front, with the Brachialis anticus; 

 behind, with the synovial membrane. 



The Posterior Ligament is a thin and 

 loose membranous fold, attached, above, 

 to the lower end of the humerus, imme- 

 diately above the olecranon depression; 

 below, to the margin of the olecranon. 

 The superficial or transverse fibres pass 

 between the adjacent margins of the ole- 

 cranon fossa. The deeper portion consists 

 of vertical fibres, which pass from the 

 upper part of the olecranon fossa to the 

 margin of the olecranon. This ligament 

 is in relation, behind, with the tendon of 

 the Triceps and Anconeus ; in front, with 

 the synovial membrane. 



The Internal Lateral Ligament is a 

 thick triangular band of ligamentous 

 fibres, consisting of two distinct portions, 

 an anterior and posterior. The anterior 

 portion, directed obliquely forwards, is 

 attached, above, by its apex, to the front 



part of the internal condyle of the humerus ; and, below, by its broad base, to the 

 inner margin of the coronoid process. The posterior portion, also of triangular 

 form, is attached, above, by its apex, to the lower and back part of the internal 

 condyle ; below, to the inner margin of the olecranon. This ligament is in rela- 

 tion, internally, with the Triceps and Flexor carpi ulnaris muscles, and the ulnar 

 nerve. 



The External Lateral Ligament (fig. 133) is a short and narrow fibrous fasci- 

 culus, less distinct than the internal, attached, above, to the external condyle of 

 the humerus ; below, to the orbicular ligament, some of its most posterior fibres 

 passing over that ligament, to be inserted into the outer margin of the ulna. 

 This ligament is intimately blended with the tendon of origin of the Supinator 

 breves muscle. 



The Synovial Membrane is very extensive. It covers the margin of the arti- 

 cular surface of the humerus, and lines the coronoid and olecranon depressions on 

 that bone ; from these points, it is reflected over the anterior, posterior, and lateral 



