Walking performance, medical outcomes and patient training in FES of innervated muscles for ambulation by thoracic-level complete paraplegics.

OBJECTIVE: To discuss functional electric stimulation (FES) gait training of upper motoneuron spinal cord injured complete paraplegics considering ambulation performance, physiologic and metabolic responses as well as psychologic outcome, while providing myologic insight into ambulation via FES when training starts many years post-injury.
METHODS: Transcutaneous FES using the Parastep stimulation system, gait training methods with and without major emphasis on muscle reinforcement, cardiovascular and respiratory conditioning. Examination of myofiber tissues and correlation of normal muscles histology versus innervated muscles of upper motor neuron and of denervated muscles of lower motor neuron paraplegics.
RESULTS: Published works in literature reviewed in this paper report average walking distance of 440 m/walk when major muscle reinforcement and preconditioning cardiovascular and respiratory systems precedes gait training, versus average 115 m/walk when undergoing direct gait training. Medical, metabolic and psychologic outcomes, as reported in several works, point to benefits of FES walking, including 60% increase in blood flow to lower extremities. Myofiber tissues of patients with upper motor neuron paralysis compare well with those of normal tissue even many years post-injury, while adipose tissue substitute muscle fibers in patients with lower motor neuron lesions. DISCUSSION: Transcutaneous FES allows considerably longer walking distances and speed at the end of training when training involves an extensive pre-conditioning program than with direct gait training. Medical and psychologic benefits are observed, especially concerning blood flow to the lower extremities. Myofiber examinations provide myologic understanding of effectiveness of FES many years post-injury.