Abductor digiti minimi of hand

The abductor digiti minimi (Latin: musculus abductor digiti minimi) is one of the muscles of the little finger. Together with the opponens digiti minimi and flexor digiti minimi brevis, the abductor digiti minimi forms the hypothenar eminence. Therefore, it is also known as one of the hypothenar muscles. The abductor digiti minimi lies on the ulnar side of the palm, stretching between the pisiform bone and the proximal phalanx of the fifth finger. The abductor digiti minimi is the most superficial of the hypothenar muscles, and it lies superior to the flexor digiti minimi brevis and opponens digiti minimi muscles.

Origin

The abductor digiti minimi muscle originates from the flexor retinaculum and the pisiform bone.

Insertion

The abductor digiti minimi inserts on the base of the proximal phalanx of the fifth finger.

Action

The primary function of the abductor digiti minimi muscle is the abduction of the little finger at the fifth metacarpophalangeal joint.

Innervation

The abductor digiti minimi is innervated by the deep branch of the ulnar nerve that arises from the brachial plexus (C8, T1).

Blood supply

The abductor digiti minimi muscle receives arterial blood supply from the branches of the ulnar artery.