Developed by Russian scientist G A Illizarov in '60s, the device is an assembly of heavy cage-like device called fixator which is put across the deformed limb.

Normally fixators are made by stainless steel rings and wires. Replacement of steel rings with indigenous carbon rings made fixators 25 per cent lighter enabling handicapped children move and carry out their exercises with more ease.

The life-style of polio victims could be changed with these low cost and reusable carbon ring-based fixators, O P Bahl, who along with his colleagues at the National Physical Laboratory (NPL) have developed the carbon rings, told newsmen here.

There are about 10 million polio patients in India who are likely to be benefitted from these carbon composite rings, he said. Carbon ring-based fixators were used on 25 patients in Agarwal Orthopaedic Hospital inGorakhpur and in the Life Line express train since last year with 100 per cent success, Agarwal from the same hospital who was in charge of clinical trial, said.

Other limb deformities could also be corrected by carbon ring-based fixators, he said. The apparatus can be set up for lengthening or shortening of bones. A minor, pin-hole surgery, is done sometimes depending upon the bone condition.

The technique, not very popular in India because of the high fixator cost, helps elongate bones up to eight inches at a rate of 0.5-2 millimetre per day.

Developed in a three-year project supported by the Department of Science and Technology (DST), the carbon rings are better substitutes to stainless steel rings as they are lighter, cheaper, reusable and transparent to X-rays, Bahl said.

"Imported carbon rings cost about Rs 15,000 whereas our rings are worth Rs 1000-1200 only," Bahl said. Unlike steel rings that can withstand only 90 kg weight, carbon rings can support weight up to 200 kg.