Anatomy & Physiology: Muscles—Lumbricals.
Structure.
- Origin: lateral sides of tendons and flexor digitorum profundus of each finger.
- Insertion: lateral sides of tendons of extensor digitorum on proximal phalanges of each finger.
Function.
- Concentric action: flexes each finger at metacarpophalangeal joints and extends fingers at interphalangeal joints. Lesser: abduct and adduct fingers II-V at MCP joints.
- Reverse mover action: extend proximal phalanges at PIP and DIP; flex metacarpals at MCP; abduct/adduct metacarpals at MCP.
- Eccentric action: controls/restrains/slows flexion, extension, adduction/abduction of fingers II-V at MCP.
- Isometric action: stabilizes MCP and interphalangeal joints of fingers II-V.
- Innervation: median and ulnar nerves.
- Arterial supply: branches of radial and ulnar arteries.
Clinical Significance.
More.
- https://www.anatomynext.com/lumbricals-of-hand/
- https://www.youtube.com/watch?v=vvm4fkNkiDM
- https://www.youtube.com/watch?v=H_481JVpc5U
- https://www.youtube.com/watch?v=7a2A2Elt3cE
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.
