Opponens pollicis at a glance
- What it is
- A thenar muscle lying deep to abductor pollicis brevis that allows the thumb to oppose.
- Location
- Originates from the tubercle of the trapezium and the flexor retinaculum and inserts onto the lateral half of the palmar surface of the first metacarpal.
- Function
- Opposes the thumb by flexing and medially rotating the first metacarpal at the carpometacarpal joint, bringing the thumb pad toward the fingertips.
- Body system
- Muscular · paired (left and right)
- FMA ID
- FMA37390 (Foundational Model of Anatomy)
Key facts
- Innervation: recurrent branch of the median nerve (C8–T1); the ulnar nerve occasionally contributes
- Blood supply: mainly the superficial palmar branch of the radial artery
Clinical relevance
Median nerve injury at the carpal tunnel can weaken thenar muscles and impair opposition.
Structures next to the opponens pollicis
The nearest named structures in the 3D model, measured from the centre of each part:
- Abductor pollicis brevis · muscular
- Superficial head of flexor pollicis brevis · muscular
- Flexor pollicis brevis · muscular
- First metacarpal bone · skeletal
- Oblique head of adductor pollicis · muscular
- Trapezium · skeletal
- Trapezoid · skeletal
- Extensor indicis · muscular
- Deep palmar arch · cardiovascular
- Dorsal carpal branch of radial artery · cardiovascular
References
- Foundational Model of Anatomy: Opponens pollicis (FMA37390). EMBL-EBI Ontology Lookup Service.
- OpenStax. Anatomy and Physiology 2e, §11.2 Naming Skeletal Muscles. Rice University, 2022.
- Mitsuhashi N. et al. (2009). BodyParts3D: 3D structure database for anatomical concepts. Nucleic Acids Research 37, D782–D785. Data © The Database Center for Life Science, CC BY 4.0.
Related anatomy
Explore the whole body in the interactive 3D human anatomy model, or browse the A–Z list of human structures.