A peroneus longus (PL) to Achilles tendon transfer is done to restore strength across the ankle joint. Strength may have been lost due to an injury to the Achilles tendon or a neurological disorder. Also, patients with Achilles tendon pain that has not improved from non-surgical treatment may benefit from this transfer. Other tendons (such as the tendon to the big toe or lesser toes) may be chosen for the transfer instead of the PL, based on the underlying anatomy and function.