Corpus: Flexor digiti minimi brevis muscle

Origin

The muscle originates along with the opponens digiti minimi muscle from the hamulus of the hamate bone and the band structures of the flexor retinaculum. From there, it extends obliquely towards distal and medial, embedded between the other deep hypothenar muscles.

Insertion

The muscle's short tendon inserts on the ulnar side of the base of the proximal phalanx of the little finger (Digitus manus V). Some fibers radiate laterally into the dorsal aponeurosis of the little finger.

The development of the flexor digiti minimi brevis muscle can vary greatly between individuals. In some cases, the muscle may be completely absent.

The innervation of the flexor digiti minimi brevis muscle is provided by the deep branch of the ulnar nerve from the brachial plexus (segments: C8 and Th1).

The muscle's blood supply is provided by branches of the ulnar artery and the superficial palmar arch. The venous blood flows into the venous networks of the palm and from there, among other routes, into the ulnar vein.

The flexor digiti minimi brevis muscle is responsible for the flexion (bending) of the little finger at the metacarpophalangeal joint.

The term "brevis" in muscle names generally indicates that there is also a muscle with the name "longus". Indeed, the flexor digiti minimi longus muscle is almost never developed in humans but is a rare anatomical variation.