Muscle
Adductor pollicis
Adducts the thumb (Froment sign)
High-yield
Ulnar-innervated thumb muscle; positive Froment sign (uses FPL to pinch) in ulnar palsy.
Overview
A deep two-headed muscle in the palm that adducts the thumb; its weakness underlies Froment's sign in ulnar nerve palsy.
Reference facts
- Origin
- Oblique head: bases of 2nd-3rd metacarpals, capitate. Transverse head: anterior 3rd metacarpal
- Insertion
- Medial base of the proximal phalanx of the thumb
- Action
- Adducts the thumb toward the palm
- Innervation
- Deep branch of the ulnar nerve (C8, T1)
- Blood supply
- Deep palmar arch
Frequently asked questions
What does the adductor pollicis do?
The adductor pollicis adducts the thumb toward the palm.
What nerve innervates the adductor pollicis?
The adductor pollicis is innervated by the deep branch of the ulnar nerve (C8, T1).
Where does the adductor pollicis attach?
Origin: Oblique head: bases of 2nd-3rd metacarpals, capitate. Transverse head: anterior 3rd metacarpal. Insertion: Medial base of the proximal phalanx of the thumb.
What is the blood supply of the adductor pollicis?
The adductor pollicis is supplied by the deep palmar arch.