246 MUSCLES OF THE HAND. 



arises from the trapezium and annular ligament ; the internal portion 

 from the trapezoides and os magnum. They are both inserted into 

 ths base of the first phalanx of the thumb, having a sesamoid bone in 

 each of their tendons to protect the joint. 



Fig. 102.* 



Relations. By its superficial surface with the external portion of 

 the palmar fascia. By its deep surface with the adductor pollicis, 

 tendon of the flexor carpi radialis, and trapezio-metacarpal articulation. 



* The muscles of the hand. 1. The annular ligament. 2, 2. The origin 

 and insertion of the abductor pollicis muscle ; the middle portion has been re- 

 moved. 3. The flexor ossis metacarpi, or opponens pollicis. 4. One portion 

 of the flexor brevis pollicis. 5. The deep portion of the flexor brevis pollicis. 

 6. The adductor pollicis. 7, 7. The lumbricales muscles, arising from the 

 deep flexor tendons, upon which the numbers are placed. The tendons 

 of the flexor sublimis have been removed from the palm of the hand. 

 8. One of the tendons of the deep flexor, passing between the two terminal 

 slips of the tendon of the flexor sublimis to reach the last phalanx. 9. The 

 tendon of the flexor longus pollicis, passing between the two portions of the 

 flexor brevis to the last phalanx. 10. The abductor minimi digiti. 11. The 

 flexor brevis minimi digiti. The edge of the flexor ossis metacarpi, or ad- 

 ductor minimi digiti, is seen projecting beyond the inner border of the flexor 

 brevis. 12. The prominence of the pisiform bone. 13. The first dorsal inter- 

 osseous muscle. 



