THE UPPER LIMB 40I 



upper part of the neck^f the radius. It also lines the coronoid, 

 radial, and olecranon fossae of the humerus, which contain small 

 cushions of fat. 



Muscular Relations. — ^The capsule is closely related to the fol- 

 lowing muscles: anteriorly, the brachialis anticus; posteriorly, the 

 triceps; externally, the extensor carpi radialis brevior and supinator 

 radii brevis; and internally, the flexor sublimis digitorum. 



Arterial Supply. — ^The superior and inferior profundae, anasto- 

 motica magna, anterior and posterior ulnar recurrent, radial 

 recurrent, and posterior interosseous recurrent, arteries. 



Nerve-supply. — ^The musculo-spiral, musculo-cutaneous, median, 

 and ulnar nerves. 



Movements. — Two movements are allowed, namely, flexion and extension, 

 these being limited by the tension of the structures related to the joint, and 

 flexion also by the coining into contact of the fleshy parts of the forearm and 

 arm. 



Muscles concerDed in the Movements — Flexion. — This is produced by the 

 biceps, brachiahs anticus, brachio-radiahs, and. as auxiliaries, the muscles 

 arising from the internal epicondyle of the humerus. Extension. — This is 

 produced by the triceps and anconeus, and, as auxiliaries, the muscles arising 

 from the external epicondyle. 



Bursa at Elbow-Joint. — The bursae in the vicinity of the elbow- 

 joint are four in number, as follows: 



Subcutaneous olecranon. Bicipito-radial. 



Deep olecranon. Epicondylar. 



The subcutaneous olecranon bursa is situated between the integu- 

 ment and the posterior triangular surface of the olecranon process 

 of the ulna. WTien this bursa becomes inflamed, it constitutes the 

 affection known as miner's elbow. It has no communication with 

 the synovial cavity of the elbow- joint. 



The deep or subtendinous olecranon bursa, which is of small size, 

 is situated upon the front part of the upper surface of the olecranon. 

 It separates the tendon of insertion of the triceps muscle from the 

 posterior ligament of the elbow-joint, and it has no communication 

 with the synovial cavity of the joint. 



The bicipito-radial bursa is situated between the tendon of 

 insertion of the biceps muscle and the anterior smooth portion ot 

 the bicipital tuberosity of the radius. It has no communication 

 with the synovial cavity of the elbow-joint. 



The epicondylar bursae are not constant. There may be two 

 }esial over the internal or mesial epicondyle of the humerus, and 



teral over the external epicondyle. 



THE RADIO-CARPAL OR WRIST-JOWT. 



,The wrist-joint belongs to the class diarthrosis, and to the sub- 

 ^vision condylarthrosis.— - The articular surfaces are the carpal 

 rface of the radius and the triangular fibro-cartilage above, and 

 jie superior facets of the scaphoid, semilunar, and cuneiform, as 

 bU as the interosseous ligaments on either side of the semilimar, 



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