But what exactly is TMR surgery? The procedure transfers remaining arm nerves to chest or upper-arm muscles, which will further provide accurate signals for controlling the hand, wrist and elbow.

 

To test how well this procedure works, Todd Kuiken, MD, PhD, from the Rehabilitation Institute of Chicago, and colleagues compared the abilities of five amputees who had had the surgery with the abilities of five people who had not had amputations.

 

The participants were instructed to perform various arm movements. Meanwhile, the researchers measured their abilities to control the virtual prosthetic arm.

 

The study found that patients undergoing TMR surgery were able to complete elbow and wrist movements in an average of 1.29 seconds, compared to 1.08 seconds for the non-amputee participants. TMR patients were able to complete hand-grasps in 1.54 seconds compared to 1.26 seconds in controls, which means that TMR surgery can be seen as an important tool to improve control of prosthetic arms and hands. Moreover, one patient had a level of control comparable to that of healthy participants, the study found.

 

“These early trials demonstrate the feasibility of using targeted muscle reinnervation to control complex multifunction prostheses,” Dr. Kuiken and colleagues wrote. However, “additional research and development need to be conducted before field trials can be performed,” they added.