Electromyographic analysis of equinovarus following stroke.

The pattern of muscle activity was determined in 40 hemiplegic stroke patients with equinus, equinovarus or varus deformities. Although the exact pattern of muscle activity varied with each patient, the following general conclusions are possible. Premature firing of the triceps surae due to release of primitive locomotor control mechanisms and a hyperactive stretch response during limb loading are important causes of equinus. Prolonged firing of the tibialis anterior during stance and inactivity of the peroneus brevis are the principal factors responsible for varus.