

Superficial Palmar ArcJi 279 



The anterior carpal joins in the anterior carpal arch beneath the 

 flexor tendons, and the posterior carpal winds beneath the flexor 

 carpi ulnaris, and then beneath the tendons at the back of the wrist, 

 to help form the posterior carpal arch. It gives off the dorsal inter- 

 osseous branches to the two inner spaces. 



Iiig-ation of the ulnar artery. In the upper part of the fore-arm 

 the artery cannot be reached by an incision in its course (p. 277), as 

 that would entail the division of the pronator teres and other muscles ; 

 it is sought, therefore, between the adjacent borders of the flexor sub- 

 limis digitorum and the flexor carpi ulnaris, by drawing a line from 

 the internal condyle of the humerus to the pisiform, and by making 

 an incision of 2j to 3 in. in that line, beginning' it ii in. below 

 the condyle. Probably this incision implicates the posterior ulnar 

 vein. The deep fascia is then exposed, and, beginning in the lower 

 end of the incision, the surgeon opens up with a director, or the handle 

 of the scalpel, the septum between those two muscles. This separation 

 is easily effected if it be begun below ; higher up the muscles are far 

 more closely connected with each other. The ulnar nerve is seen 

 lying on the flexor profundus digitorum, and after raising the flexor 

 sublimis and searching beneath it the artery is seen with its venae 

 comites. 



For ligation of the ulnar artery in the middle of the fore-arm, or 

 nearer the wrist, a 2-in. incision is made close along the radial side 

 of the tendon of the flexor carpi ulnaris. A thickish layer of fascia 

 has to be divided, and the artery is found with its venae comites. 

 The nerve is between the vessels and the tendon ; the needle must 

 therefore be passed from the inner side. 



At tlie wrist the ulnar artery continues over the annular ligament, 

 close to the radial side of the ulnar nerve and the pisiform bone. It 

 is covered by skin and superficial fascia with the transverse fibres of 

 the palmaris brevis, and by the inner part of the palmar fascia, which 

 is strengthened by a slip from the insertion of the flexor carpi 

 ulnaris. 



in the palm the artery curves downwards and outwards from the 

 pisiform to make the superficial palmar arch, the convexity of which 

 is directed towards the fingers. The position of this arch is shown by 

 abducting the thumb and drawing a line across the palm at the level 

 of the inferior, or distal, border of the web of the thumb. Sometimes 

 the ulnar artery anastomoses at its outer end with the superficialis 

 volas, but the arterial anastomosis is more usually completed by the 

 communication with the radialis indicis at the tip of the index- 

 finger. 



Relations of the superficial palmar arch. It lies close beneath 

 the integument and the strong palmar fascia, and rests upon the 

 digital branches of the median nerve, and upon the tendons of the 

 flexor sublimis digitorum. 



