THE MUSCULAR SYSTEM f$ 



Abductor Pollicis. Origin, from trapezium, scaphoid, 

 annular ligament, and palmar fascia. Insertion, first 

 phalanx of thumb. Action, abducts and flexes first pha- 

 lanx of thumb. Nerve, median. 



Opponens Pollicis. Origin, trapezium and anterior 

 ligament. Insertion, metacarpal bone of thumb. Action, 

 flexes and opposes thumb. Nerve, median, palmar divis- 

 ion. 



Flexor Brevis Pollicis. Origin, by two heads: Outer, 

 lower border of superior annular ligament and ridge of 

 trapezium; inner, os magnum, and base of first, second, 

 and third metacarpal bones. Insertion, base of first 

 phalanx of thumb. Action, flexes the thumb at meta- 

 carpal articulation. Nerve, outer head, median; inner 

 head, deep ulnar. 



Adductor Obliquus Pollicis. Origin, from os magnum, 

 second and third metacarpal bones. Insertion, base of 

 first phalanx of thumb. Action, draws the thumb inward 

 toward the middle line. Nerve, ulnar. 



Adductor Transversus Pollicis. Origin, third metacar- 

 pal bone. Insertion, base first phalanx of thumb. Ac- 

 tion, flexes the phalanx, adducts the thumb. Nerve, 

 ulnar. 



Palmaris Brevis. Origin, from the annular ligament 

 and palmar fascia. Insertion, skin on inner border of 

 palm. Action, wrinkles the skin on the palmar side. 

 Nerve, ulnar. 



Abductor Minimi Digiti. Origin, pisiform bone. In- 

 sertion, base of first phalanx of little finger. Action, draws 

 the little finger from the middle line and flexes the meta- 

 carpophalangeal joint. Nerve, ulnar. 



Flexor Brevis Minimi Digiti. Origin, from the unciform 

 bone and annular ligament. Insertion, first phalanx of 

 little finger. Action, flexes the first phalanx. Nerve, 

 ulnar. 



