FES is indicated in MS patients who present with progressive difficulty in their ability to walk. When considering FES intervention for gait improvement the patient assessment should include careful evaluation of all lower limb musculature and, particularly, the hip flexors and ankle dorsiflexors.

As dropped foot stimulation (DFS) primarily addresses difficulty with swing phase of gait and improves stride length –  it is important to accurately assess for weakness of hip and ankle musculature as gait is significantly affected by motor loss of hip flexion and ankle dorsiflexion.  Strength wise – a muscle grade of < 4/5  (where 5= normal) for hip flexion and/or ankle dorsiflexion can be considered an indication for a dropped foot stimulator.

{Hip flexion should be assessed with the patient sitting upright on a chair, ankle dorsiflexion assessed with the patient in supine lying}. Comparison of right vs left limb strength is also important.

Dropped foot stimulation can be of considerable benefit to the patient with hip flexion weakness as the electrodes can be placed to elicit a “triple flexion” response at hip, knee and ankle through stimulation of the flexion withdrawal reflex. Dorsiflexion impairment is also easily addressed with a DFS.