THE ELBOW-JOINT. 



171 



connected with a small transverse band, which bridges over the notch between the 

 olecranon and the coronoid process. 



The external lateral ligament, intimately connected with the tendinous attach- 

 ment of the extensor muscles, is shorter and narrower than the internal. It is attached 



Fig. 198. LIGAMENTS OP THE ELBOW-JOINT. (Allen Thomson.) J 



A, from the outer side and behind ; B, from the front ; C, from the inner side and behind. 1, 

 internal lateral ligament ; 2, external lateral ; 3, the middle strongest pail of the anterior ligament ; 

 4, orbicular ligament ; 5, posterior ligament, represented as wrinkled from relaxation in extension. In 

 these figures the oblique ligament and upper part of the interosseous membrane are also represented 

 below the elbow-joint. 



Fig. 199. SAGITTAL SECTION OP THK ELBOW-JOINT THROUGH THE GREAT 



SIGMOID CAVITY OF THE ULNA AND THE TROCHLEAR SURFACE OF THE 



HUMERUS. (Allen Thomson.) % 



1, cut surface of the humerus ; 2, that of the ulna ; 3, posterior part, 

 and 4, anterior part of the synovial cavity of the joint ; 5, orbicular liga- 

 ment ; 6, tendon of the biceps muscle ; 7, is at the lower end of the oblique 

 ligament. 



superiorly to a depression below the external condyle of the 

 humerus, and inferiorly becomes blended with the orbicular 

 ligament, on the surface of which its fibres can be followed 

 forwards and backwards to the extremities of the small sigmoid 

 cavity of the ulna. 



The anterior ligament consists of a thin sheet of fibres, 

 strongest in its middle part, extending downwards from above 

 the coronoid and radial fossae of the humerus to the coronoid 

 process of the ulna and the orbicular ligament. It is covered, 

 except at its outermost part, by the brachialis anticus 

 muscle, which is closely attached to it near the coronoid process. 



The posterior ligament, very thin and weak, consists of loose and irregular 

 fibres passing transversely across the olecranon fossa of the humerus, and from the 

 sides of that fossa to the olecranon process, thus completing the capsule of the joint 

 behind. Externally a rather stronger band extends from a slight depression behind 

 the capitellurn to the posterior border of the small sigmoid cavity of the ulna. The 



