Limb muscle weakness Foot dorsiflexor weakness Dorsiflexion of the foot extends the foot superiorly, as if taking the foot off the gas pedal. HP:0003377 Foot extensor weakness Footdrop SNOMEDCT_US:6077001 Foot drop UMLS:C0085684 Weakness of the muscles responsible for dorsiflexion of the foot, that is, of the movement of the toes towards the shin. The foot dorsiflexors include the tibialis anterior, the extensor hallucis longus, the extensor digitorum longus, and the peroneus tertius muscles. UMLS:C1866141 Inability to walk on heels Inability to heel walk HP:0009027