PLATE IX. 

 THE PALMAR FASCIA. 



This plate shows a superficial dissection of the lower part of the forearm, and palm 

 of the hand. The tendon of the palinaris longus after perforating the deep fascia of 

 the forearm is continued into the palmar fascia, which may be spoken of as an expansion 

 of its tendon. The palmaris brevis which arises from its inner border is the remnant 

 of the large muscular palmaris longus which exists in the armadillo, etc., and is there 

 muscular in the whole of its extent. 1 The palmar fascia with the palmaris brevis is 

 easily reflected from the underlying structures on the ulnar side of the hand, but on the 

 radial side the fascia is bound down to the annular ligament at the point where it blandl 

 with the origin of the abductor and outer head of the flexor brevis pollicis. 



The palmar fascia, as seen in the plate, is strong and triangular, being composed 

 chiefly of longitudinal fibres, continuous above with those of the tendon of the palmaris 

 longus, while below they divide into four digital slips which pass along the middle line 

 of the finger, and are closely connected with the skin ov< r the first phalanx. The four 

 digital slips are tied together by transverse fibres, which are collected, opposite the 

 metacarpo-phalangeal joint, into a well-marked bundle called the superficial transverse 

 ligament ; each slip also gives off from its deep surface two prolongations which 

 descend on either side of the flexor tendons to be attached to the glenoid plates and edges of 

 the metacarpal bone. An arch is thus formed through which the flexor tendons pass, 

 while between the arches the digital nerves and arteries, and the lumbricals pass to their 

 destination. ' It is the degenerate perforated flexor of the first phalanges.' (Macalioter.) 



1 For further information, gee the Morphology of Ligaments by Mr. J. Bland Button. 



