Tendon of second dorsal interosseous muscle

The tendons of the dorsal interossei muscles of the foot are the terminal extensions of the four dorsal interossei muscles, which are located in the intermetatarsal spaces. Each dorsal interosseous muscle arises by two heads from the adjacent sides of the metatarsal bones and converges into a single tendon distally. These tendons pass dorsally and slightly medially or laterally, depending on their position, to insert primarily onto the bases of the proximal phalanges and the dorsal digital expansion (extensor hood) of the second, third, and fourth toes.

The first dorsal interosseous tendon inserts on the medial side of the proximal phalanx of the second toe, while the second, third, and fourth dorsal interossei insert on the lateral sides of the proximal phalanges of the second, third, and fourth toes, respectively. The tendons blend with the extensor expansion, contributing to both abduction of the toes and stabilization of the metatarsophalangeal joints during gait. The anatomical arrangement allows for fine control of toe abduction and resistance to adduction forces during propulsion.