Palmaris brevis muscle is a thin, quadrilateral muscle, placed beneath the integument of the ulnar side of the hand. It acts to fold the skin of the hypothenar eminence transversally.
The first recorded observation of the muscle is by Italian anatomist Giambattista Canano sometime before 1543. The muscle was independently discovered a few years later by Realdo Colombo before being pushed to general acceptance in the works of Andreas Vesalius.[4]
Function
Palmaris brevis muscle tenses the skin of the palm on the ulnar side during a grip action.[2][3] It also deepens the hollow of the palm.[5] The palmaris brevis may protect the ulnar nerve and ulnar artery from compressive forces during repetitive grasping actions.[6] The muscle has a fatigue-resistant fiber type profile, which supports the idea of a protective function to the ulnar neurovasculature during repetitive intermittent grasping tasks.[7]