Abductor minimi digiti muscle (hand)

Abductor digiti minimi muscle of hand
The muscles of the left hand seen from palmar surface (abductor digiti minimi is shaded in bright red)
Details
Origin	Pisiform bone, the pisohamate ligament, and the flexor retinaculum
Insertion	Base of the proximal phalanx of the 5th digit on the ulnar or medial side
Artery	Ulnar artery
Nerve	Deep branch of ulnar nerve
Actions	Abducts little finger
Identifiers
Latin	Musculus abductor digiti minimi manus
Dorlands /Elsevier	m_22/12548273
TA	A04.6.02.062
FMA	37382
Anatomical terms of muscle []

In human anatomy, the abductor digiti minimi (abductor minimi digiti, abductor digiti quinti, ADM) is a skeletal muscle situated on the ulnar border of the palm of the hand. It forms the ulnar border of the palm and its spindle-like shape defines the hypothenar eminence of the palm together with the skin, connective tissue, and fat surrounding it. Its main function is to pull the little finger away from the other fingers (i.e. abduction).

The abductor digiti minimi arises from the pisiform bone, the pisohamate ligament, and the flexor retinaculum.

Its distal tendon ends in three slips that are inserted into the ulnopalmar margin of the proximal phalanx, the palmar plate of the metacarpophalangeal joint, and the sesamoid bone when present. Some fibers insert into the finger's dorsal aponeurosis, which is why the muscle acts similar to a dorsal interosseus muscle.

Additionally, the ulnar-most portion of the tendon inserts into the little finger's digital cord, and the muscle thus forms part of a structure that flexes the metacarpophalangeal joint and extends the interphalangeal joints.

It is innervated by the deep branch of the ulnar nerve (C8–T1).