50 THE SUPERIOR EXTREMITY 



nerve arises, with the result that muscles supplied by these 

 segments the biceps and the brachialis (b. anticus) may be 

 thrown into spasm. In this way the condition of " Bent Arm " 

 arises ; and it can be cured only by excision of the cicatrix. 



Superficial Veins of Elbow and Forearm. The superficial veins 

 of the forearm arise from the plexuses of the digits and hand, and, although 

 liable to variation, their arrangement at the elbow is fairly constant. The 

 Median Vein begins near the dorsal radial tubercle (p. 46), and winds round 

 the radial border of the forearm. It ends at the apex of the cubital fossa by 

 dividing into the Median Basilic and Median Cephalic veins, soon after it 

 has received its chief tributary, the profunda, from the deeper structures of 

 the forearm (Fig. 12). 



The Median Basilic passes proximally and medially, superficial to the 

 lacertus fibrosus (bicipital fascia), and in front of the medial epicondyle it 

 joins the Basilic vein, which ascends from the ulnar side of the hand. There- 

 after the basilic vein ascends in the medial bicipital furrow as far as the 

 insertion of the coraco-brachialis, where it pierces the deep fascia (p. 34). 

 The Cephalic vein, which arises on the radial side of the hand, is joined by the 

 median cephalic in front of the lateral epicondyle. It passes proximally 

 on the deep fascia over the lateral aspect of the biceps brachii and enters the 

 groove between the deltoid and the pectoralis major, which conducts it to 

 the superficial infra-clavicular triangle. 



It is important to recognise that most of the venous return from the hand 

 and forearm passes by the profunda to the median and then to the basilic 

 and cephalic veins, which are superficially placed, whereas only a small pro- 

 portion returns by the vense comites of the brachial artery. 



On this account the venous return is easily controlled, and the arm is 

 therefore suitable for the purpose of Bier's congestive treatment in acute 

 infective conditions. 



Bandages, too tightly applied, very easily produce such oedema and 

 pressure that Volkmann's ischaemic contracture or even gangrene of the 

 limb may follow. 



Volkmann's Ischsemic Contracture produces a deformity in which 

 the fingers and wrist gradually assume a flexed attitude, owing to an inter- 

 stitial fibrosis of the flexor muscles of the forearm. When the wrist is 

 passively extended, the flexion of the fingers is increased, as the fibrosed 

 flexor muscles cannot stretch. The extensor muscles become stretched 

 and weakened by the constant flexion of the fingers, and they appear to be 

 paralysed. On flexion of the wrist, which loosens the flexors and over- 

 stretches the extensors, it will be found that the extensors of the fingers are 

 able to produce a weak movement, a feature which serves to differentiate 

 the condition from radial (musculo-spiral) paralysis (p. 102). 



The median basilic and median cephalic are the veins 

 commonly used for transfusion of saline or for intravenous 

 injection of drugs. They may be rendered prominent by allowing 

 the arm to hang downwards for a few minutes or by applying 

 a bandage round the arm tight enough to constrict the veins 

 without affecting the artery. 



The Lymph Vessels of the digits and hand are closely 

 associated with the superficial veins, and the main trunks 

 accompany the bigger veins in the forearm. Those of the ulnar 



