Phantom Limb in Virtual Reality

Losing a major limb can be devastating, but what many of us don't know is that a major challenge for amputees is something called phantom pain. About 70% of amputees live with it and find it debilitating. The pain often and randomly spikes, causing surges of intense pain, interfering with sleep and daily activities. But a new treatment involving virtual reality may help relieve their pain.

Scientists hooked up electrodes to the stumps of arms of fourteen patients. The electrodes sent signals from the nerves in the stumps to a computer so that the patient could control a virtual arm that was superimposed onto the patient's stump. They were trained to use their thoughts to control the virtual arm and drive a virtual car in a race. They also copied the movements of an onscreen arm with their own virtual arm.

After twelve 2-hour sessions, the patients had follow-up interviews one, three, and six months later. Rather than constant pain, these patients reported an average of 50% less pain and impact on their sleep and daily activities. One patient even felt pain-free periods, where his amputated hand felt relaxed rather than constantly clenched.

The training requires the patients to use areas of the brain required for arm movement. Since these areas may be intertwined with circuits responsible for pain perception, the treatment may be disentangling movement from pain. It also trains patients to use the nerves and muscles in the stump to control the missing limb even when not hooked to the computer, so the relief could be lasting. If larger studies confirm these results, thousands of amputees will live better quality lives.