Opponens pollicis muscle

Opponens pollicis muscle

Opponens pollicis muscle
The deep muscles of the right hand. Dorsal surface.
The superficial muscles of the right hand. Palmar surface.
Details
Latin Musculus opponens pollicis
Origin trapezium and transverse carpal ligament
Insertion metacarpal bone of the thumb on its radial side
Superficial palmar arch
Recurrent branch of the median nerve
Actions Flexion of the thumb's metacarpal at the first carpometacarpal joint, which aids in opposition of the thumb
Dorlands
/Elsevier
m_22/12549981
Anatomical terms of muscle

The opponens pollicis is a small, triangular muscle in the hand, which functions to oppose the thumb. It is one of the three thenar muscles, lying deep to the abductor pollicis brevis and lateral to the flexor pollicis brevis.

Contents

  • Structure 1
    • Innervation 1.1
    • Blood supply 1.2
  • Function 2
  • Additional images 3
  • References 4

Structure

The opponens pollicis originates from the flexor retinaculum of the hand and the tubercle of the trapezium. It passes downward and laterally, and is inserted into the whole length of the metacarpal bone of the thumb on its radial side.

Innervation

Like the other thenar muscles, the opponens pollicis is innervated by the recurrent branch of the median nerve.

Blood supply

The opponens pollicis receives its blood supply from the Superficial palmar arch.

Function

Opposition of the thumb is a combination of actions that allows the tip of the thumb to touch the tips of other fingers. The part of opposition that this muscle is responsible for is the flexion of the thumb's metacarpal at the first carpometacarpal joint. This specific action cups the palm. Many texts, for simplicity, use the term opposition to represent this component of true opposition. In order to truly oppose the thumb, the actions of a number of other muscles are needed at the thumb's metacarpophalangeal joint.

Additional images

References

This article incorporates text in the public domain from the 20th edition of Gray's Anatomy (1918)