Palmaris Brevis
Original Editor - Oyemi Sillo
Top Contributors - Oyemi Sillo and Rishika Babburu
Description
Palmaris Brevis is a small cutaneous muscle that lies in the fascia over the hypothenar eminence.[1]
Origin
It originates from the flexor retinaculum and palmar aponeurosis.[2]
Insertion
It inserts on the skin of the medial border of the hand.[2]
Nerve
The Palmaris Brevis is innervated by the superficial branch of the ulnar nerve.[2]
Artery
It is supplied by the superficial palmar arch.[2]
Function
Palmaris Brevis improves the palmar grip action by pulling on the skin over the hypothenar muscles, which deepens the hollow of the palm.[1] This action creates a more effective cupping shape of the hand, enhancing the ability to hold and manipulate objects securely. By tightening the skin on the ulnar side of the palm, the muscle also helps protect the ulnar nerve and artery during gripping activities, preventing them from being compressed against hard surfaces or objects.
The palmaris brevis is unique among hand muscles as it's one of the few that acts primarily on skin rather than bone or joints. This skin-based function becomes particularly important during power grip activities, where the deepened palm hollow allows for better contact with cylindrical objects like tool handles or sports equipment.
Clinical relevance
The innervation of the Palmaris Brevis is by the only motor component of the superficial branch of the ulnar nerve.[3] This is makes it possible to diagnose the site of lesions to the ulnar nerve at the wrist, based on whether palmaris brevis function is affected or not. It may also help to protect the ulnar nerve and ulnar artery from compression in the ulnar canal during repetitive grasping motions.[3]
References
- ↑ 1.0 1.1 Jenkins DB. Hollinshead's Functional Anatomy of the Limbs and Back, 9th edition. Elsevier Health Services, 2008.
- ↑ 2.0 2.1 2.2 2.3 Drake, RL, Vogl, W., Mitchell, AWM, Tibbitts, R., Richardson, P., Horn, A., & Gray, H. (2020). Gray's anatomy for students .
- ↑ 3.0 3.1 Moore, C., & Rice, C. (2017, August 08). Structural and functional anatomy of the palmaris brevis: Grasping for answers. Retrieved October 22, 2020, from https://onlinelibrary.wiley.com/doi/full/10.1111/joa.12675