For the first time, engineers have enabled paralysed people to stand up and balance for significant periods without holding an external support. This is an important breakthrough in helping individuals with spinal cord injuries to start standing again for useful lengths of time – up to seven minutes have been achieved in experiments.
The research project that achieved this advance was carried out by the Department of Mechanical Engineering at the University of Glasgow with funding from the Swindon based Engineering and Physical Sciences Research Council.
The project focused on the development and evaluation of techniques that use low levels of pulsed electrical current to stimulate the nerves that control muscle movement. The current replaces signals from the brain, which do not reach the nerves on account of the spinal cord injury. This electrical stimulation makes the paralysed muscle contract and partially restores lost body functions.
The initiative has built on earlier work by the same research team – an acknowledged leader in the field and the first to demonstrate, in practice, unsupported standing for paraplegics. The challenge was to allow spinally-injured people to stand in a stable fashion for significant periods of time, without having to hold on to a frame or walker. The team has achieved this by stimulating the muscles controlling the ankle by an amount directly related to the person’s standing posture. For example, if the person leans further forward, the stimulation is automatically increased to push them back to a more upright position. The approach is known as feedback control.
The team is led by Professor Ken Hunt, Head of the University’s Centre for Rehabilitation Engineering. The research was carried out in close collaboration with the Queen Elizabeth National Spinal Injuries Unit at Glasgow’s Southern General Hospital. Professor Hunt says: ‘Enabling spinally-injured people to stand again and remain balanced for this amount of time represents major progress. This has never been achieved before in experiments with human subjects’.