128 THE SUPERIOR EXTREMITY 



supplied by the distal branch of the dorsal cutaneous nerve of 

 the forearm, which is a branch of the radial nerve. 



Four nerves supply the skin of the palm of the hand : in 

 the region of the hypothenar eminence the palmar cutaneous 

 branch of the ulnar nerve, in the region of the thenar emin- 

 ence the lateral cutaneous nerve of the forearm, and a twig from 

 the superficial division of the radial nerve, whilst the inter- 

 mediate part is supplied by the palmar cutaneous branch of the 

 median nerve. 



Two nerves supply branches to the skin of the dorsum of 

 the hand: on the lateral part the superficial branch of the 

 radial nerve, and on the medial part the dorsal branch of the 

 ulnar nerve. 



Two nerves supply the skin of the volar aspects of the 

 digits : the median and the ulnar. Three and a half digits fall 

 to the digital branches of the median nerve : the thumb, the 

 index, the middle, and the lateral half of the ring finger ; and 

 one and a half to the digital branches of the ulnar nerve, the 

 little finger and the medial half of the ring finger. 



Three nerves supply the skin of the dorsal aspects of the 

 digits. Speaking generally, the proximal halves of the thumb, 

 the index, middle, and half the ring finger are supplied by 

 branches of the superficial division of the radial nerve. The 

 distal halves of the index, middle, and half the ring finger 

 are supplied by twigs of the digital branches of the median nerve, 

 and the remaining half of the ring finger and the little finger 

 receive twigs from the ulnar nerve. 



After the cutaneous veins and nerves have been re- 

 examined the deep fascia of the forearm should be thoroughly 

 cleaned, if that has not already been done, and its special 

 points should be re-studied. 



Fascia Antibrachii (Fascia of the Forearm). The deep 

 fascia which envelops the forearm is of considerable strength 

 and density. More particularly is that the case on the dorsal 

 aspect of the limb. In its proximal part it receives an 

 accession of fibres from the tendon of the biceps brachii, in 

 the form of the lacertus fibrosus. Some fibres are given to 

 it by the tendon of the triceps also. Near the elbow it 

 serves as a surface of origin for the numerous muscles which 

 spring from the epicondyles of the humerus, and from its 

 deep aspect dense septa pass between the fleshy bellies. The 

 septal partitions are indicated on the surface by a series of 



