Functional electrical stimulation

Functional electrical stimulation, Stroke, Muscle

Functional Electrical Stimulation (FES) can be used to help people who have had a stroke to lift their foot when walking. This was first done in 1960 by an American bioengineer called Liberson. For some time after this the idea was not developed, mainly because the technology was neither reliable nor user-friendly.

During the last decade research at Salisbury District Hospital, in conjunction with Surrey University in Guildford, Kings College London, and more recently Southampton University has made FES much more effective and useful.

The people most likely to benefit are those who have a drop-foot that causes them to either trip or hitch their hip when they walk. It is not suitable for people who are unable to walk. Work is also being done to apply the techniques to arm problems and it seems to be useful with people who have some arm function but who, for example, lack the ability to open the hand even though they have quite a good grip.

The principle of FES is to replace the nerve impulses to the muscles that are interrupted by damage to the brain or spinal cord with small electrical signals. It can be used not only with people who have had a stroke, but also people with spinal cord or head injuries, MS or cerebral palsy. It seems that it is particularly useful when people have spasticity (muscle stiffness).

The simplest stimulator is one that activates the muscles that lift the foot during walking. A switch worn in the shoe triggers the stimulation and the electrical signals reach the muscles through electrodes stuck to the skin of the leg, just below the knee. The stimulator is about the size of a pack of cards and can be worn at the waist on the belt or in a pocket. Leads connect the stimulator to the switch in the shoe and the electrodes on the leg.

Research has shown that when stimulation is effective the person can walk faster, with less effort and with more confidence. Stimulators are continuing to be developed, computer technology is allowing them to be more finely controlled and more muscle groups can be stimulated to produce a more natural walking pattern.

People with dropped foot following a stroke who think they may benefit from FES should first contact their GP or hospital consultant. If they feel it might be suitable they can make a referral to:

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