thenar eminence
The intrinsic muscles of the hand are divided into three groups:
(1) those of the thumb, the thenar eminence
(2) those of the little finger, the hypothenar eminence
(3) and those in the middle of the palm and between the metacarpal bones.
The muscles of the thenar eminence are:
adductor policis (transverse)
adductor policis (oblique)
flexor pollicis brevis
abductor policis brevis
opponens pollicis
The forearm (extrinsic hand muscles) that control the thumb are:
abductor pollicis longus
extensor pollicis brevis
extensor pollicis longus
flexor pollicis longus