Opponens digiti minimi muscle
Encyclopedia
The opponens digiti minimi (opponens digiti quinti in older texts) is a muscle
in the hand
. It is of a triangular form, and placed immediately beneath the palmaris brevis, abductor minimi digiti, and flexor brevis minimi digiti. It is one of the three hypothenar muscles that controls the little finger.
It arises from the convexity of the hamulus
of the hamate bone
, and contiguous portion of the transverse carpal ligament; it is inserted into the whole length of the metacarpal bone of the little finger, along its ulnar margin.
Opponens minimi digiti serves to flex and laterally rotate the 5th metacarpal about the 5th carpometacarpal joint
, as when bringing little finger and thumb into opposition. It is innervated by the deep branch of the ulnar nerve.
Muscle
Muscle is a contractile tissue of animals and is derived from the mesodermal layer of embryonic germ cells. Muscle cells contain contractile filaments that move past each other and change the size of the cell. They are classified as skeletal, cardiac, or smooth muscles. Their function is to...
in the hand
Hand
A hand is a prehensile, multi-fingered extremity located at the end of an arm or forelimb of primates such as humans, chimpanzees, monkeys, and lemurs...
. It is of a triangular form, and placed immediately beneath the palmaris brevis, abductor minimi digiti, and flexor brevis minimi digiti. It is one of the three hypothenar muscles that controls the little finger.
It arises from the convexity of the hamulus
Hamulus
Hamus, Hamulus and words derived from them, are morphological or anatomical terms in various branches of biology. They describe structures functioning as, or in the form of, hooks or hooklets.-Derived terms:...
of the hamate bone
Hamate bone
The hamate bone is a bone in the human hand that may be readily distinguished by its wedge-shaped form, and the hook-like process which projects from its volar surface. It is situated at the medial and lower angle of the carpus, with its base downward, resting on the fourth and fifth metacarpal...
, and contiguous portion of the transverse carpal ligament; it is inserted into the whole length of the metacarpal bone of the little finger, along its ulnar margin.
Opponens minimi digiti serves to flex and laterally rotate the 5th metacarpal about the 5th carpometacarpal joint
Carpometacarpal joint
The carpometacarpal joints are five joints in the wrist that articulates the distal row of carpal bones and the proximal bases of the five metacarpal bones....
, as when bringing little finger and thumb into opposition. It is innervated by the deep branch of the ulnar nerve.