Trial of the Finetech Implanted Dropped Foot Stimulator following incomplete spinal cord injury
Funded by INSPIRE
1 year from Jan 2004 (estimated)
The incidence of incomplete Spinal Cord Injury (ISCI) in the UK is estimated at 17 per million of population per year, about 65% of all spinal cord injuries. In recent years the incidence has risen in comparison to complete spinal cord injuries, mainly due to improved care in the acute stage of the injury. Within this group there is a wide spectrum of disability ranging from functionally normal individuals to those that are profoundly disabled. Many individuals are able to achieve walking but with significant gait deficit, the most significant factor being a dropped foot, the inability to lift the foot as it is swung forward in the swing phase of gait.
The Odstock dropped foot stimulator has been successfully used with many people who have an ISCI. It has been demonstrated that walking speed and mobility are improved by the device.
However, there are some problems using skin surface electrodes. It is often difficult to correctly locate the position for the electrodes and it can be time consuming for the user each time they put the device on. The skin can also react to the electrodes, coursing a skin irritation. Finely the sensation of the electrical stimulation can be quite strong which can discourage some potential users.
The Fineteck Implanted Dropped Foot Stimulator avoids these problems by locating electrodes directly on the nerves that produce the movements. Internally there is a small receiver stimulator with two leads connecting to the electrodes. Externally the user wares a transmitter box that passes power and control signals to the receiver by radio telemetry. The device is timed to walking using a foot switch placed inside the shoe. When weight is taken off the switch, stimulation starts and the foot is lifted. Stimulation stops when weight is returned to the switch.
The device has been used in ten people who have had a stroke and found to be safe and effective. We now wish to perform a trial with people who have had spinal cord injuries to see if they may also benefit from its use. Three centres, Stoke Mandeville, Southern General and Salisbury, will be part of this project, each recruiting seven subjects. Each subject's suitability for FES will be determined by using and skin surface FES system for three months. If they respond well they will go on to use the implanted device. Assessments will be made to determine the effect on walking speed, walking effort, walking endurance, falls, disability and quality of life. This application requests funds for the Salisbury part of the trial at a cost of £22,952.60.
Paul Taylor, Anba Soopramanien and John Hobby