THE MUSCLES 97 



(43) Flexor carpi ulnaris ; (Fig. 54) by two heads, one from 

 the medial epicondyle of humerus, the other from the medial 

 aspect of the olecranon to pisiform bone. The two heads are 

 separated by the ulnar nerve, but unite before reaching the 

 middle of the ulna. Flexor of hand. 



(44) Flexor sublimis digitorum (or perforatus) (Fig. 56); 

 by two heads, one from the palmaris longus near the wrist, the 

 other from the flexor profundus digitorum; coalesce near 

 origin then sends tendons which are perforated by the flexor 

 profundus digitorum near their insertion onto the bases of the 

 second row of phalanges; flexor of the second phalanx of the 

 four ulnar digits. 



(45) Flexor profundus digitorum (or perforans) ; (Fig. 56) five 

 heads which join at the wrist; first head from proximal end of 

 ulna; second head from medial epicondyle of humerus; third 

 and fourth heads from medial epicondyle; fifth head from ventral 

 surface of shaft of radius; the common tendon of the wrist 

 divides into five tendons, four of which perforate the tendons of 

 the sublimis at the bases of the first phalanges; to be inserted 

 in the base of the terminal phalanx of each digit. Flexor of all 

 digits. 



(46) Pronator quadratus (Fig. 56); ventral surface of ulna 

 and adjacent interosseus membrane to ventral surface of radius; 

 pronator of hand. 



MUSCLES OF HAND 



For a more complete description the student is referred to 

 Reighard and Jennings. 



(47) Lumbricales ; four small muscles in palm of hand from 

 the tendon of the flexor profundus to the radial side of the base 

 of first phalanx of the four ulnar digits; bends digits mediad. 



(48) Abductor pollicis brevis (includes opponens poUicis of 

 man); transverse ligament on radial side of wrist to base of 

 phalanx of thumb; abducts thumb. 



