DISSECTION OF THE UPPER EXTREMITY 97 



Superficial Fascia of Palm. 



Note the subdivision of the fat into lobules. Study 



(a) The short palmar muscle (M. palmaris brevis). After examination 



cut through its origin and reflect it ulnarward, avoiding injury to 

 ulnar artery and nerve. 



(b) Cutaneous nerves of palm. 



(ba) Eamus palmaris N. mediani. 



(bb) Eamus cutaneus palmaris N. ulnaris. 

 (be) Eamus superficialis N. radialis. 



FIG. 34. 



Surface markings of the palm of the hand. The thick black lines represent the chief creases in the 

 skin. (After Treves, Surg. Ap. Anat., London, 1889, 4th ed., p. 260, Fig. 26. ) 



Deep Fascia of Palm (Aponeurosis palmaris). 



Clean the surface of this and note its three parts. 



(a) Radial or thenar aponeurosis. 



(b) Middle or principal palmar aponeurosis. 



(c) Ulnar or hypothenar aponeurosis. 



(a) and (c) are relatively thin; (b) is very thick. What is 

 the shape of (b)? To what does the base of the triangle corre- 

 7 



