Plantar interossei

Plantar interossei:
Proximal attachment – medial side of metatarsals 3 to 5
Distal attachment – medial side of proximal phalanges of digits 3 to 5; MPJ joint capsules; extensor expansion
Open chain function – adduction of digits to line of 2nd digit
Closed chain function – stabilises digits on ground during propulsion
Nerve supply –lateral plantar (deep branch  1st & 2nd interossei; superficial branch  3rd interossei)