O: Hook of hamate and flexor retinaculum I: Medial side of base of proximal phalanx of little finger A: Flexes proximal phalanx of little (5th) finger WikipediaQuestions
O: Humerus ulna head I: Bodies of middle phalanges of digits 2 - 5 A: Flexes middle phalanges at proximal interphalangeal joints of medial four digits; acting more strongly, it also flexes proximal phalanges at metacarpophalangeal joints and hand WikipediaQuestions
