New amputation surgery could increase control and reduce pain for patients
A new type of surgery could help amputees control their remaining muscles and sense where their “phantom limb” is in space, which should mean better control of prosthetic limbs and less pain for patients, according to a study of the new procedure.
A research team at the Massachusetts Institution of Technology said that most amputations sever the muscle pairs that control affected joints – such as ankles or elbows – but by reconnecting these pairs, it allows them to retain their normal ‘push-pull’ function, which would give amputees better sensory feedback.
Researchers measured the precision of movement in the ankle and a foot joint after amputation in 15 amputees who had received the new procedure (agonist-antagonist myoneural interface or AMI) for amputations below the knee, and in 7 patients who had traditional amputations.
During surgery, the first group had two sets of muscles reconnected – those controlling the ankle and the muscles controlling the subtalar joint (which allows the sole of the foot to tilt). This group said they were able to control their muscles more precisely, as well as feeling more freedom of movement and less pain in the affected limb.
Lead author of the study, Shriya Srinivasan, said:
"Both our study and previous studies show that the better patients can dynamically move their muscles, the more control they're going to have. The better a person can actuate muscles that move their phantom ankle, for example, the better they're actually able to use their prostheses."
Another version of the new procedure is being developed for different types of amputations, such as above and below the elbow and below the knee. Furthermore, researchers have also developed a version that can be used for those who have had a traditional amputation – this involves grafting small parts of muscle which serve as the agonist / antagonist muscles for an amputated joint, called regenerative AMI.
The study was published in Proceedings of the National Academy of Sciences.
"This is very interesting and potentially promising news. Fashioning a strong and receptive stump is vital for all amputees to enable a resumption of activities they were able to enjoy before the loss of a limb. Advances in this field will improve prosthetic use which paves the way to increased independence, ability to work, play sport and other activities and ultimately lead a full life."
Richard Edwards is a Partner within the Personal Injury team here at Potter Rees Dolan. If you would like to speak to Richard or any of our expert serious injury solicitors regarding amputation claims, please call 0800 027 2557 or fill out the contact form at the bottom of this page. Alternatively, you can contact Richard directly here.