Muscles of the ankle and foot function to move the ankle, foot, and toes and some are located in the lower leg. The muscles attach to the femur (upper leg bone), tibia, and fibula (lower leg bones) and to various bones in the foot. They are also responsible for moving the foot upward (dorsiflexion) or downward (plantar flexion), and turning the sole of the foot inward (inversion) or outward (eversion).
The dorsal flexor muscles include the following: The tibialis anterior is a dorsal flexor and is an elongated, spindle-shaped muscle located on the front of the lower leg. It arises from the surface of the tibia to pass on the inside over the far end of the tibia, and attaches to bones of the ankle and foot. Contraction of the tibialis anterior causes dorsiflexion and inversion of the foot. The peroneus tertius is a muscle of variable size that connects the fibula to the outside of the foot. It functions in dorsiflexion and eversion of the foot. The extensor digitorum longus is situated along the outside of the lower leg, just behind the tibialis anterior. It comes from close to the midline of the tibia and the shaft of the fibula. Its tendon divides into four parts as it passes over the front of the ankle. These parts continue over the surface of the foot and attach to the four smaller toes. The actions of this muscle include dorsiflexion of the foot, eversion of the foot, and extension of the toes.