Connection lost. Please refresh the page.
Online
Get help How to study Login Register
Ready to learn?
Pick your favorite study tool

Adductor pollicis muscle

Recommended video: Adductor pollicis muscle [02:23]
Attachments, innervation and functions of the adductor pollicis muscle.
Adductor pollicis muscle (Musculus adductor pollicis)

Adductor pollicis is a triangular intrinsic muscle of the hand. Although it is found in the thenar region of the hand, the adductor pollicis is the sole muscle of the adductor compartment of the hand, and does not form part of the thenar muscle group, which includes the abductor pollicis, flexor pollicis brevis, and opponens pollicis

Adductor pollicis is comprised of two heads; oblique and transverse. This muscle extends from the third metacarpal and capitate bones to the base of the first proximal phalanx. The main action of this muscle is adduction of the thumb in the carpometacarpal joint.

In this article, we will discuss the anatomy and function of the adductor pollicis muscle.

Key facts about the adductor pollicis muscle
Origin Transverse head: Palmar base of metacarpal bone 3 
Oblique head: Capitate bone, palmar bases of metacarpal bones 2 & 3
Insertion Medial base of proximal phalanx 1 (via ulnar sesamoid bone)
Action Carpometacarpal joint 1: Thumb adduction
Innervation Deep branch of ulnar nerve (C8, T1)
Blood supply Deep palmar arch
Contents
  1. Origin and insertion
  2. Relations 
  3. Innervation
  4. Blood supply
  5. Function
  6. Sources
+ Show all

Origin and insertion

Adductor pollicis arises by two heads which originate from different locations. The transverse head originates from the palmar base of the third metacarpal bone, while the oblique head originates from the capitate bone and palmar bases of second and third metacarpals. From their origin points, the two heads converge into one muscle belly as the fibers run laterally towards the thumb.

The muscle ends in a tendon that contains a sesamoid bone and inserts onto the base of the first proximal phalanx as well as its extensor hood.

Relations 

The adductor pollicis muscle is larger than and deeper to the thenar muscles. On its ventral aspect, adductor pollicis is crossed by the flexor tendons of the index finger, first lumbrical and flexor pollicis brevis muscles. On its dorsal aspect, the muscle is related to or even sometimes conjoined with the first dorsal interosseous muscle. In addition, the two heads of adductor pollicis comprise a passageway through which the deep branch of ulnar nerve, deep palmar arch and radial artery pass.

Innervation

Adductor pollicis muscle receives its innervation from the deep branch of ulnar nerve (root value C8, T1).

Blood supply

Adductor pollicis is vascularized by the deep palmar arterial arch, formed by the anastomosis of the radial artery and the deep palmar branch of ulnar artery.

Function

Adductor pollicis is the most powerful of the intrinsic muscles of the hand. Its main function is the adduction of the thumb which is the movement of the thumb towards the index finger from an abducted position. This action is essential for functions that require pinching and gripping. Additionally, the adductor pollicis aids the later stages of opposition of the thumb.

This movement is a combination of actions, namely adduction, medial rotation, flexion and adduction of the thumb so that it can touch each fingertip of the same hand. Thus, the strength of adductor pollicis can be tested by pushing the thumb against the index finger while the examiner attempts to pull them apart. 

Test your knowledge on the muscles of the hand with this quiz.

Adductor pollicis muscle: want to learn more about it?

Our engaging videos, interactive quizzes, in-depth articles and HD atlas are here to get you top results faster.

What do you prefer to learn with?

“I would honestly say that Kenhub cut my study time in half.” – Read more.

Kim Bengochea Kim Bengochea, Regis University, Denver
© Unless stated otherwise, all content, including illustrations are exclusive property of Kenhub GmbH, and are protected by German and international copyright laws. All rights reserved.

Register now and grab your free ultimate anatomy study guide!