MONDAY, Sept. 9, 2019 (HealthDay News) — After losing a lower leg, Savo Panic received a prosthetic limb that helped restore movement. But prostheses are imperfect, and he suffered tremendous “phantom” leg pain.
Now, European scientists say they’ve developed a technology that restores natural feeling and improves walking in patients who’ve had a lower leg amputation. The approach also eliminated phantom pain in Panic and reduced it in another volunteer.
Using sensors that connect the leg prosthesis to remaining nerves in the thigh, the technology enables patients to feel the same sensations they would if their real leg were still there. Sensations like pressure and touch. This makes walking more surefooted and boosts endurance.
With a leg prosthesis, you can’t judge where the limb is, how it is moving or what surface it’s on. You can’t completely trust it.
“We implemented our technology within the residual nerves of above-knee amputees in order to restore them to sensations of movement, which they were missing for many years,” lead researcher Stanisa Raspopovic said at a media briefing Friday. He is a professor at the ETH Zurich Institute of Robotics and Intelligent Systems, in Switzerland.
“Immediately, post-implant persons can describe sensations as close to lifelike ones,” Raspopovic said.
Because the sensations are being created by the patients’ own brain, they don’t need training to get up and moving, he said.
Walking improves because the patients don’t have to rely on their one real leg to provide all the sensation of walking. That can be exhausting, the researchers explained.
The reduction in phantom pain is an added benefit of this new prosthesis.
Panic said he wakes up at night from phantom pain. “The toe that I don’t have hurts. My big toe, foot, heel, ankle, calf — they all hurt, and I don’t even have them,” he said in an ETH news release.
“Since I have started this treatment program, after having received electrical stimulations, I don’t feel any phantom pain,” Panic said.
The other patient’s pain didn’t disappear completely, but was greatly reduced, the researchers noted.