Model-based development of neuroprostheses for restoring proximal arm function.

Neuroprostheses with the use of functional neuromuscular stimulation (FNS) have the potential to restore elbow and shoulder function lost to paralysis because of spinal cord injury (SCI). The human shoulder is highly flexible and thus provides a large range of motion to the arm and hand, although at the expense of precarious stability of the articulations. The complexity of the shoulder has prevented widespread use of FNS at this joint. However, musculoskeletal modeling of the elbow and shoulder has the potential to significantly speed the development of neuroprostheses by allowing many mechanical issues to be resolved in simulation prior to implementation in human subjects. This paper describes our rationale for the use of musculoskeletal modeling, the model we are using, and several practical applications of the model to study the potential use of shoulder and elbow muscle FNS to restore function following cervical SCI.