Nerve implant that helps paraplegics to walk again

briefing: Science

Crippled patients are being helped to stand and walk with an implant that stimulates the roots of paralysed nerves, it was revealed yesterday. One woman who smashed her spine in a car accident about seven years ago is now able to walk a few steps with assistance - and ride a tricycle.

The new device is called a Lumbar Anterior Root Stimulator Implant (LARSI) which is surgically placed in the spine. Unlike other implants it stimulates the roots of nerves rather than the point at which they enter the muscles.

Two paraplegic patients have been given the implant by a team of doctors led by Dr Nick Donaldson, from University College London.

They reported in the Lancet medical journal yesterday that the first patient, who underwent surgery in December 1994, has now been standing regularly for more than two years. Although her standing posture was still unsatisfactory, she had been able to take 24 consecutive steps while being guided by helpers. In addition, the combination of joint movements available meant she was able to ride a tricycle or cycle machine.

The second patient, a man, has just begun to stand six months after implantation. It is too early to say how successful his treatment has been.

The battery-powered implant is activated by the patient using a small control box.