This clinical protocol proposes an iteration of the RPNI model, with the intent of incorporating these surgical constructs into the design of lower limb amputations at the time of limb sacrifice. Given the success of this technique to date, the investigators believe that incorporation of innervated muscle segments into residual limb design has the potential to provide lower limb amputees with a biological interface for unprecedented prosthetic motor control that is not only high resolution but also highly intuitive and capable of restoring limb proprioception. In addition, it is anticipated that allowing amputees to have greater control of advanced prostheses may offer the potential to normalize gait kinematics, thereby correcting alterations in energy expenditure that have been previously reported. Such measures hold the promise of optimizing the functional and overall health of lower limb amputees, thereby reducing the morbidity currently associated with the amputee status.