Flexor digiti minimi brevis muscle of hand

Origin and insertion

Flexor digiti minimi brevis muscle arises by a short tendon from the hook of hamate bone and medial aspect of flexor retinaculum. From here the muscle fibers run distally and medially, passing over the fifth metacarpophalangeal joint. The muscle inserts together with abductor digiti minimi onto the medial side of the base of proximal phalanx of the little finger.

Relations 

Flexor digiti minimi brevis muscle is located on the ulnar side of the palm, creating the hypothenar eminence with abductor digiti minimi and opponens digiti minimi muscles.

The muscle is situated inferior and lateral to adductor digiti minimi muscle and superior and medial to opponens digiti minimi muscle. The proximal parts of flexor digiti minimi brevis and abductor digiti minimi muscles form a gap through which deep branches of the ulnar artery and ulnar nerve pass. 

Innervation

The flexor digiti minimi brevis, like other hypothenar muscles, is innervated by the deep branch of the ulnar nerve (root value C8 and T1).

Blood supply

Flexor digiti minimi brevis muscle receives its blood supply from the deep palmar branch of ulnar artery. 

Function

The main function of the flexor digiti minimi brevis is flexion of the little finger at the metacarpophalangeal joint. Also, this muscle participates in lateral rotation and opposition of the little finger.