Abductor Digiti Minimi of Hand (Left) (Musculus abductor digiti minimi)
Educational content only — not medical advice.
Anatomy
The most superficial and largest of the three hypothenar muscles, forming the medial border of the palm. It arises from the pisiform and the tendon of flexor carpi ulnaris and inserts with a fibrous slip onto the extensor hood as well as the proximal phalanx — so it abducts through both joints of the little finger's base. It is the most powerful of all the finger abductors thanks to its long lever arm.
Origin & insertion
From the pisiform and the tendon of flexor carpi ulnaris, to the ulnar side of the base of the proximal phalanx of the little finger and its extensor hood.
Action
Abducts the little finger away from the ring finger and assists its metacarpophalangeal flexion.
Innervation
Deep branch of the ulnar nerve (C8–T1).
Clinical notes
Wasting of this muscle hollows the hypothenar eminence and is an early, visible sign of an ulnar nerve lesion at the elbow (cubital tunnel). Its strength is graded when localising ulnar motor function below and above Guyon canal.
Related structures
Educational references
FAQ
What is the role of the Abductor Digiti Minimi of Hand (Left)?
The most superficial and largest of the three hypothenar muscles, forming the medial border of the palm. It arises from the pisiform and the tendon of flexor carpi ulnaris and inserts with a fibrous slip onto the extensor hood as well as the proximal phalanx — so it abducts through both joints of the little finger's base. It is the most powerful of all the finger abductors thanks to its long lever arm.
Why is the Abductor Digiti Minimi of Hand (Left) clinically important?
Wasting of this muscle hollows the hypothenar eminence and is an early, visible sign of an ulnar nerve lesion at the elbow (cubital tunnel). Its strength is graded when localising ulnar motor function below and above Guyon canal.
Source & license
BodyParts3D, © The Database Center for Life Science licensed under CC Attribution 4.0 International (https://creativecommons.org/licenses/by/4.0/). license details