Mathematically Modeling the Effects of Electrically Stimulating Skeletal Muscle

A framework for modeling the activation of skele- tal muscle is presented for studying Functional Electrical Stimulation. A mathematical model of the cellular responses of skeletal muscle, created at AgResearch (Ruakura, New Zealand www.agresearch.co.nz), has been integrated with an anatomical, finite element model of the semitendinosus muscle, which was constructed from CT scans of the hind limb of a sheep. The tibial nerve was also constructed from digitized CT scans, and has been modeled using the Hodgkin Huxley neural model. The relevant cellular equations have been solved over these geometries. The results obtained, i.e speed of action potential propergation through the nerve and muscle, and the duration of twitch force, agree with published values.