Virtual system eases phantom limb pain

LONDON (Reuters) - British scientists said on Tuesday they have developed a virtual reality system that can help amputees cope with phantom pain by giving them the illusion that their missing limb is still there.

Phantom limb pain is mysterious pain felt by the amputee where the limb used to be. Children born without a limb can feel a similar sensation.

"Many people who undergo an amputation experience a phantom limb," said Dr. Craig Murray, of the University of Manchester who headed the project. "These are often very painful for the person concerned. They can persist for many years, and are very difficult to treat."

The system he and his team developed uses a headset and sensors to transport patients into a virtual world where they see themselves with two limbs that they can control and move to do tasks and play games.

So far the scientists, who presented their findings at a science meeting in Denmark, have tested it on five patients including a woman who suffered from phantom limb pain for 40 years.

Each patient had between 7 and 10 sessions lasting 30 minutes over 2 to 3 months. Four out of the five who used the system reported improvements in their phantom limb pain.

"One patient felt that the fingers on her amputated hand were continually clenched into her palm, which was very painful for her. However, after just one session using the virtual system she began to feel movement in her fingers and the pain began to ease," Murray said.

Previous research has suggested that tricking a person's brain into believing the missing limb can be seen and moved could ease the pain.

There has also been some evidence showing that stimulating the motor cortex region of the brain that controls movement can diminish phantom limb pain.

The scientists are planning to test the virtual reality system on more patients to identify which amputees are most likely to benefit from it.