Drop foot is a chronic condition, often caused by a stroke which is characterised by the inability to raise the foot during the swing phase of walking. People affected tend to have a laboured and unsafe gait, and suffer from fatigue which further reduces their speed and the distance they can walk.
The current approaches for dropped foot correction have significant drawbacks. "Either the ankle joint is fixed by a brace, or electrical stimulation is applied to a nerve in the leg through electrodes attached to the skin surface. The electrodes must be placed accurately, which is difficult, painful and time consuming," says Professor Dr Hermie Hermens, cluster manager at the Dutch lead partner, Roessingh Research and Development BV.
"The new system, in contrast to the surface stimulators, has an implanted component that is directly attached to the appropriate nerves, eliminating the problems of electrode placement. Also, the electrical stimulation is not painful as the stimulation current does not pass across the skin," explains Hermens.
The project used technology developed by the UK project partner, FineTech Medical, through its work on bladder stimulation. The device is implanted during surgery and produces the dual, balanced signals required to produce the correct walking action.
A clinical trial is currently testing the device and patients' reactions to it. Feedback is excellent - patients are able to walk better, faster and further, with a more normal gait.
Although the device is a world first and is expected to generate a market of 30,000 units a year, the partners first have to explain the benefits to patients and demons
Contact: Paul McCallum