[TA] four intrinsic muscles of second layer of plantar muscles; origin, first: from tibial side of tendon to second toe of flexor digitorum longus; second, third, and fourth: from adjacent sides of all four tendons of this musculus; insertion, tibial side of extensor tendon on dorsum of each of the four lateral toes; action, flex the proximal and extend the middle and distal phalanges; nerve supply, lateral (second to fourth lumbricals) and medial (first lumbrical) plantar. SYN: musculus lumbricalis pedis [TA].