Plantar Interossei
Origin = Third through fifth metatarsals, tibial side.
Insertion = Bases of the first phalanges of the third through fifth toes, tibal side.
Action = Addution of the metatarsophalangeal joints of the third, fourth, and fifth toes; flexes the metatarsophalangeal joints and extends the interphalangeal joints of the third, fourth, and fifth toes.