There are constantly new discoveries being made and inventions that move medicine forward, and the field of orthotics and prosthetics is no exception. During the development of bio-prosthetic limbs that use the body’s own electric signals to cue and control the prosthetic, it was discovered that rewiring severed nerves could benefit amputees in several ways. This is called targeted muscle reinnervation, or TMR for short.
Phantom limb pain has not always been well understood by doctors, but it is a commonly reported symptom after amputations. The severed nerve endings are still trying to send signals the areas that are no longer there, and the disorganization can result in the experience of pain, and formation of neuromas. Targeted muscle reinnervation can reduce these problems by connecting severed nerve endings to other nearby nerves in muscles. This rewiring allows new nerve connections to form and gives the signals somewhere to go.
Targeted muscle reinnervation can also help improve the performance of new prosthetics, giving the user more precise control and higher function in the prosthetic. Targeted muscle reinnervation is not right for every prosthetic user. It works best for those who have experienced above-elbow or shoulder amputations within the last ten years. Good candidates for this type of surgery should also have stable, soft tissue and need to be willing to participate in extensive rehabilitation and physical therapy to help them as they learn to use their advanced prosthesis. Targeted muscle reinnervation can even be performed during the amputation process if possible, rather than needing to be a separate surgery.