Targeted Muscle Reinnervation (TMR) 

Targeted muscle reinnervation (TMR) relieves limb pain in some amputees and allows for the use of more advanced prosthetics. Targeted muscle reinnervation (TMR) is essentially a way to give nerves affected by an amputation procedure something to do. When they’re rerouted into muscle as motor nerves, they’re less likely to send pain signals to the brain while they are attempting to regenerate properly. And when the nerve endings innervate a muscle, the brain is led to believe that the amputated limb is still attached to a patient’s body. This enables those who have had an arm amputated to have a greater degree of control over a prosthetic limb. 

Conditions Treated 

While TMR surgery was originally developed with the intent of giving patients the ability to use advanced prosthetics, it has also been found to relieve painful conditions that many amputees experience after their primary surgery, including: 

• Phantom limb pain (the sensation of pain in an area that no longer exists) 
• Residual limb pain, including that which affects prosthetic usage 
• Neuromas (painful tissue scarring) 

Procedure Details 

A TMR procedure can be performed at the same time as an amputation (primary TMR) or sometime after the amputation (secondary TMR). In this procedure, a surgeon will move residual nerves from the amputated limb to muscles that are no longer functioning and surgically separated from their native motor nerve input. 

What to Expect 

TMR surgery takes two to four hours and requires a hospital stay of up to five days. If a patient is getting a new prosthetic limb, the fitting process will begin at least one month after the surgery and the prosthesis will come several weeks afterward. Risks of this procedure include: 

• Blood clotting 
• Complications from anesthesia 
• Excessive bleeding and pain 
• Infection 

Effectiveness 

While recovery times vary from patient to patient, TMR surgery is generally successful at relieving pain. There will be a major learning curve for patients who opt to use more advanced prosthetics (especially for arm amputees), but those who undergo training will find they can do much more with their new prostheses than before and gain more independence than they had with their old ones. 

At Tampa General Hospital’s Orthopaedic Institute, our nationally renowned experts use cutting-edge technology to achieve world-class outcomes for patients undergoing targeted muscle reinnervation and other orthopaedic procedures.