TMR Nerve Reassignment Surgery Offers Pain Relief For Amputees
NEW YORK (CBSNewYork) - Those who lose a limb often live with intense pain that seems to be coming from the part of the body that's no longer there.
A new application of a surgical procedure can bring amputees relief and help them get back to their daily lives.
The nearly two million Americans who have lost a limb and face a lot of challenges. Relearning how to perform simple tasks with a prosthetic takes time and patience. For a lot of amputees, this adjustment is nearly impossible due to constant pain caused by severed nerves.
After doctors discovered dangerous blood clots, Robert Haas had emergency surgery to amputate his left leg. Even with daily medicine to help his recovery, excruciating pain kept him off his feet.
"Drugs can only mask the pain. They don't cure the pain," Haas said.
His pain was caused by neuromas, disorganized bundles of nerve endings that form after amputation surgery. It's a common side effect, as is phantom limb pain, which occurs when severed nerves send signals to an area that's no longer there. Phantom limb pain affects up to 75 percent of amputees.
"Think of it like a live wire. If you cut a live wire, you've got electrical shocks kind of going through, so they'll say, I'm having really shock type pain or burning pain," said Dr. Ian Valerio of the Ohio State Wexner Medical Center.
So researchers there began studying targeted muscle reinnervation, or TMR. Originally developed to work with new technology in bioprosthetic limbs, they noticed amputees who had TMR surgery also reported a significant reduction in both neuroma and phantom limb pain.
"And that's when we opened our eyes and said, 'Maybe we actually missed some of the boat here.' It's not just the movement or sensation, it could be the pain that we're actually impacting as well, which can be just as beneficial," said Dr. Valerio.
The procedure connects amputated nerves to a nearby muscle group, creating new connections and giving those previously disconnected signals somewhere to go.
"In some ways, it's somewhat tricking the brain into saying, 'Well, the amputated foot is still there,' because the nerve that was going to the foot now has something to do again," said Dr. J. Byers Bowen.
When TMR was performed at the time of amputation, resesarchers found that only 13 percent of patients reported pain six months later. TMR can also be performed on patients like Robert, who have waited for relief for years.
"When I woke up, the pain was gone," he said.
Experts say they hope TMR at the time of amputation will become standard practice in amputation surgeries in the future.
In addition to reducing pain, new advancements in artificial limbs will include sensors that can actually read those new nerve connections created during TMR surgery and allow amputees to move their prosthetics just like any other limb.