Structures

  • Supinator
  • Abductor pollicis longus
  • Extensor pollicis brevis
  • Extensor pollicis longus
  • Extensor indicis

MuscleActionOriginInsertionInnervationBlood supply
Supinator- Supination
- Lateral epicondyle of humerus
- Radial collateral ligament
- Annular ligament
- Supinator crest of ulna
- Lateral, posterior and anterior surfaces of proximal 1/3 radius- Posterior interosseous nerve: C5,6 - Recurrent interosseous artery
Abductor pollicis longus- Abducts and extends thumb at carpometacarpal joint- Posterior surface of ulna, radius and interosseous membrane- Base of 1st metacarpal- Posterior interosseous nerve: C7,8- Posterior interosseous artery
Extensor pollicis brevis- Extends proximal phalanx of thumb at carpometacarpal joint- Posterior surface of radius and interosseous membrane- Base of proximal phalanx of thumb- Posterior interosseous nerve: C7,8- Posterior interosseous artery
Extensor pollicis longus- Extends distal phalanx of thumb at carpometacarpal and interphalangeal joints- Posterior surface of middle 1/3 of ulna and interosseous membrane- Base of distal phalanx of thumb- Posterior interosseous nerve: C7,8- Posterior interosseous artery
Extensor indicis- Extends 2nd digit -Posterior surface of ulna and interosseous membrane- Extensor expansion of 2nd digit- Posterior interosseous nerve: C7,8- Posterior interosseous artery