Occurs in excessively pronated feet during the late stance phase when the flexor digitorum longus get a mechanical advantage over the interossei muscle. The quadratus plantae muscle does not pull the tendon of flexor digitorum longus laterally as it should when the foot is pronated adductovarus position of 4th and 5th digits. The flexor muscles fire early and longer to stabilise the hypermobile forefoot clawing or hammering of toes. The toes are visualised during gait as ‘grasping’ the ground during late midstance and propulsive phases. Probably the most common cause of claw and hammer toes.