Anatomy & Physiology: Muscles—Abductor Pollicis Longus.
Structure.
- Origin: posterior surface of middle of radius and ulna and interosseous membrane.
- Insertion: first metacarpal.
Function.
- One of four deep distal four group.
- Concentric action: abducts and extends thumb at carpometacarpal joint and abducts hand at wrist joint. Lesser: lateral rotation of thumb at CMC; radial deviation; wrist flexion; supination.
- Reverse mover action: abducts and extends thumb at carpometacarpal joint and abducts hand at wrist joint. Lesser: lateral rotation of thumb at CMC; radial deviation; wrist flexion; supination.
- Eccentric action: controls/restrains/slows thumb adduction, flexion, medial rotation at CMC; adduction, flexion, and lateral rotation of trapezium at CMC; wrist ulnar deviation and extension; pronation.
- Isometric action: stabilize first CMC, wrist, radioulnar joints.
- Innervation: deep radial nerve.
- Arterial supply: posterior interosseus artery, perforating branches of anterior interosseus artery.
Clinical Significance.
References
Biel, A. (2015). Trail guide to the body: A hands-on guide to locating muscles, bones and more.
Cedars-Sinai. (2018). Vertebrae of the spine. Retrieved from https://www.cedars-sinai.org/health-library/diseases-and-conditions/v/vertebrae-of-the-spine.html
Clark, M., Lucett, S., Sutton, B. G., & National Academy of Sports Medicine. (2014). NASM essentials of corrective exercise training. Burlington, MA: Jones & Bartlett Learning.
Jenkins, G., & Tortora, G. J. (2012). Anatomy and Physiology: From Science to Life, 3rd Edition International Stu. John Wiley & Sons.
Muscolino, J. E. (2017). The muscular system manual: The skeletal muscles of the human body.