THE MUSCLES OF THE HAND. 



609 



Nerve-Supply. — By the deep division of the ulnar nerve from the eighth cer- 

 vical and first thoracic nerves. 



Action.— To fiex and at the same time adduct the fifth metacarpal. 



7. Flexor Brevis Minimi Digiti (Figs. 577, 578). 



Attachments.— The short flexor of the little finger (m. flexor brevis digiti 

 quinti) lies along the lateral (radial; border of the abductor minimi digiti. It arises 



Fig. 588. 



Radius- 

 Anterior interosseous artery 



Ulna 



Pronator quadratus 



, Cut edge of 



anterior annular ligament 



Oppoiiens pollicis 

 Abductor pollicis 



Flexor brevis pollicis 

 First palmar interosseus 



Flexor longus 

 pollicis tendon 



Flexor carpi ulnaris tendon 



Cut edge of 

 anterior annular ligament 



Pisiform bone 



Adductor pollicis, oblique portion 



Third palmar interosseus 



Fourth palmar interosseus 

 Fourth dorsal interosseus 



Deep dissection of wrist and hand, showing pronator quadratus and short muscles of thumb. 



from the anterior annular ligament and the uncinate process of the uncinate bone 

 and is inserted into the ulnar side of the base of the first phalanx of the little finger. 



Nerve-Supply. — By the deep division of the ulnar nerve from the eighth cer- 

 vical and first thoracic nerves. 



Action. — To flex and slightly abduct the first phalanx of the little finger. 



Variations. — The flexor brevis and opponens minimi digiti are often united by muscle- 

 bundles and may even be completely fused. 



39 



