SURGICAL ANATOMY OF THE PALM. 163 



the digital vessels takes place a little nearer the palm 

 than the web of the fingers, and their course is subse- 

 quently along the under lateral aspects of the digits. 

 The skin is very sensitive, notwithstanding the horny 

 condition it acquires in those who have much manual 

 labor, and it is furrowed by ridges, in which lie the 

 orifices of the sweat-ducts. The great vascularity of the 

 skin of the palm predisposes this region to the occur- 

 rence of erectile tumors. 



Dissection. The subcutaneous tissue is full of lobu- 

 lated fat ; beneath the fat and cellular tissue is the palmar 

 fascia, particularly strong in its central fasciculus, and 

 into the posterior portion of which is inserted the pal- 

 maris longus; opposite the heads of the metacarpal bones 

 it divides into four slips, which slips themselves will be 

 seen to divide into two processes, attached to the sides 

 of the first phalanx, giving passage to the flexor ten- 

 dons, whilst the intermediate spaces transmit the digital 

 vessels and nerves. Vertical septa pass down and divide 

 the central set of palmar muscles from the thenar and 

 hypothenar, the expansion of the palmar fascia covering 

 which is very thin. This palmar aponeurosis is fre- 

 quently the seat of contraction which implicates the 

 fingers. The little palmaris brevis muscle is attached to 

 the skin and ulnar aspect of the central portion of the 

 aponeurosis. On removing the palmar fascia the under- 

 lying structures are met with in the following order, 

 dissecting down to the metacarpus. 



Commencing with the thenar eminence beneath the 

 fascial covering, lie the superficialis volse artery, abduc- 

 tor pollicis, opponens pollicis, and radial head of short 

 flexor of thumb, tendon of flexor longus pollicis, ulnar 

 head of flexor brevis pollicis, princeps pollicis, and 



