A surgical technique known as targeted muscle reinnervation
appears to enable patients with arm amputations to have improved
control of functions with an artificial arm, according to a
study in the February 11 issue of JAMA. Currently available
prostheses following upper-limb amputation do not adequately
restore the function of an individual's arm and hand. The most
commonly used prostheses are body-powered, which capture
remaining shoulder motion with a harness and transfer this
movement through a cable to operate the hand, wrist, or elbow.
With this control method, only one joint can be operated at a
time, according to background information in the article.
Improving the function of prosthetic arms remains a challenge,
because access to the nerve-control information for the arm is
lost during amputation. With the surgical procedure, targeted
muscle reinnervation (TMR), remaining arm nerves are transferred
to chest or upper-arm muscles that are no longer biomechanically
functional due to loss of the limb. Th