A Novel Approach to Upper Extremity Amputation to Augment Volitional Control and Restore Proprioception

A fishmouth incision will be made. Radial and ulnar (BEA) or humoral (AEA) osteotomies will be performed. Segments of the flexor carpi radialis (FCR), extensor carpi radialis longus (ECRL), flexor digitorum profundi (FDP), extensor digitorum communis (EDC), flexor pollicis longus (FPL) and extensor pollicis longus (EPL) will be isolated, as well as the biceps (B) and triceps (T) groups in the AEA model; if it is not possible to preserve native innervation to these muscles, functional motor units will be constructed from muscle coapted to the appropriate motor nerve endings. Sensory nerve endings of the distal median, ulnar and radial nerves will then be isolated and redirected to discrete skin patches in the proximal residual forearm or proximal brachium. Coaptation of the FCR/ECRL, FDP/EDC, FPL/EPL and B/T muscles will then be performed to promote dynamic coupling of these agonist/antagonist pairs. The skin envelope will then be closed in layers over percutaneous drains.

Amputation is performed via standard techniques at either the BEA or AEA level. No construction of agonist-antagonist muscle pairs will be performed.