interossei of hand (anatomy)
Last reviewed 01/2018
The interosseous muscles arise from between the metacarpal bones. They are arranged in two layers of four small muscles. The palmar interossei sit nearer the palmar surface and are unipennate. The dorsal interossei are situated deeper to the palmar interossei in relation to the palm. They are bipennate.
Although they both share some functions with respect to digital movement (see submenu), they diverge in relation to abduction and adduction:
- P.almar interossei AD.duct the fingers towards the midline; beloved of examiners, this function can be recalled with the acronym 'PAD'
- D.orsal interossei AB.duct the fingers; acronym 'DAB'
The interosseous muscles are supplied by the deep branch of the ulnar nerve.