Dorsiflexion of the foot

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Bones and ligaments that form the ankle joint.

Dorsiflexion of the foot is a movement that occurs in the sagittal plane exclusively at the ankle joint. It is the upward motion of the foot so that its dorsal (superior) surface approaches the shin, reducing the angle between them, hence the '-flexion' part of the name. The range of dorsiflexion possible at the ankle joint varies depending on knee position. With the knee straight (extended) about 10 degrees of dorsiflexion is possible, whilst this increases to around 30 degrees with a flexed knee. 

Dorsiflexion of the foot is facilitated by the muscles in the anterior compartment of the leg: tibialis anterior, extensor digitorum longus, extensor hallucis longus and fibularis tertius. Conversely the posterior leg muscles restrict the movement, in addition to the joint capsule, the posterior part of the medial collateral ligament and the calcaneofibular ligament. Although its not a movement which produces a large amount of force, its particularly important during the gait cycle, lifting the foot and toes to prevent them from dragging along the ground.