464 ULNAR NERVE. BRANCHES. 



posterior aspect of the wrist it joins a large and remarkable ganglion, 

 which gives off a number of branches for the supply of the joint. 



The Superficial palmar branch arises from the median nerve at 

 about the lower fourth of the fore-arm : it crosses the annular ligament, 

 and is distributed to the integument over the ball of the thumb and in 

 the palm of the hand. 



The median nerve at its termination in the palm of the hand is 

 spread out and flattened, and divides into six branches, one muscular 

 and five digital. The muscular branch is distributed to the muscles of 

 the ball of the thumb. The digital branches send twigs to the lumbri- 

 cales muscles and are thus arranged : two pass outwards to the thumb 

 to supply its borders ; one to the radial side of the index finger ; one 

 subdivides for the supply of the adjoining sides of the index and mid- 

 dle fingers; and the remaining one, for the supply of the adjoining 

 sides of the middle and ring fingers. The digital nerves in their course 

 along the fingers are situated to the inner side of the digital arteries. 

 Opposite the base of the first phalanx each nerve gives off a dorsal 

 branch which runs along the border of the dorsum of the finger. Near 

 the extremity of the finger the digital nerve divides into a palmar and 

 a dorsal branch ; the former supplying the sentient extremity of the 

 finger, and the latter the structures around and beneath the nail. The 

 digital nerve maintains no communication with its fellow of the oppo- 

 site side. 



The ULNAR NERVE is somewhat smaller than the median, behind 

 which it lies, gradually diverging from it in its course. It arises from 

 the brachial plexus in common with the internal head of the median 

 and the internal cutaneous nerve, and runs down the inner side of the 

 arm, to the groove between the internal condyle and olecranon, rest- 

 ing upon the internal head of the triceps, and accompanied by the infe- 

 rior profunda artery. At the elbow it is superficial, and supported by 

 the inner condyle, against which it is easily compressed, giving rise to 

 the thrilling sensation along the inner side of the fore-arm and little 

 finger, ascribed to striking the "funny bone." It then passes between 

 the two heads of the flexor carpi ulnaris and descends along the inner 

 side of the fore-arm, crosses the annular ligament, and divides into 

 two branches, superficial and deep palmar. At the commencement of 

 the middle third of the fore-arm, it becomes applied against the artery, 

 and lies to its ulnar side, as far as the hand. 



The Branches of the ulnar nerve are, 



Muscular in the upper arm, Dorsal branch, 



Articular, Superficial palmar, 



Muscular in the fore-arm, Deep palmar. 

 Anastomotic, 



The Muscular branches in the upper arm are a few filaments distri- 

 buted to the triceps. 



