The application of FES to Multiple Sclerosis induced weakness is possible, as the nerve fibers are still intact, making it an upper motor neuron disease. The applications are focussed on the clinical presentation of the patient, and are often in the form of a single channelof stimulation to improve a dropped foot. A dropped foot is brought on by the inability of the muscles of the foot to lift it up during the swing phase of walking. This often results in tripping and even falling. A conventional approach might include Physiotherapy rehabilitation, the use of walking aids, and at times, an ankle-foot orthosis is used to keep the foot in a lifted position.
FES offers an alternative to this treatment, encouraging active movement of the foot, and by constantly taking the foot through the full range of movement with walking, avoids stiffening up of the ankle. Improvements are reflected in objective tests, recording the speed of walking and the effort of walking by measuring the heart rate. Common reports are of walking being made easier, quicker, and safer, with patients feeling a lot more confident in walking about. Carry-over of these improvements may be found when looking at unstimulated walking too, although due to the progressive nature of this disease, are not as pronounced as in Stroke patients. Other improvements are also found in decreasing calf tone and improving range of movement, and peripheral circulation. Improved standing symmetry is also encouraged due to the nature of the foot switch-stimulation relationship.
Two channels of stimulation are also used at times, in order to integrate another set of muscles into the walking pattern. This might include the hamstring muscles to improve knee bending when bringing the foot forwards, or to the gluteal muscles to bring the body over the effected leg when standing. Bilateral dropped foot stimulation is not uncommon in MS patients. Exercise stimulation may also be applied to the leg in order to improve the effect of the above-mentioned systems, or to the upper limb. This could be done using the 2-channel or 4-channel stimulator.