Application of functional neuromuscular stimulation to children with spinal cord injuries: candidate selection for upper and lower extremity research.

This paper summarizes the results of screening for participation in research programs involving functional neuromuscular stimulation (FNS). It examines the characteristics of a group of children and teenagers with spinal cord injuries (SCI) identified as potential candidates for FNS as defined by the rigorous inclusion criteria of the research studies. One hundred and thirteen children and teenagers under the age of 20 with cervical, thoracic or lumbar level spinal cord injuries were examined for inclusion in an experimental program of FNS to provide standing, walking, or prehension. Although biased towards adolescents with complete midthoracic and midcervical injuries, the age, sex, injury level, etiology, and neurological status of the sample coincided with previously published reports and consisted predominantly of teenage males injured in motor vehicle or sports related accidents. Approximately half of the individuals examined were physically appropriate for research participation without preparatory intervention. Treatment options to prepare individuals for FNS were identified in 25% of those considered inappropriate at the initial evaluation, indicating that the potential user population of clinical systems may be larger than estimates obtained from research applications. Peripheral denervation was the single most prevalent physical impediment to the application of FNS. Although the incidence of lower motor neuron (LMN) involvement was similar in subjects with tetraplegia and paraplegia, those with cervical lesions more frequently exhibited other medical complications that interfered with the application of FNS. Surgical procedures involving transfer of paralyzed but excitable muscles were identified in almost one third of the candidates with tetraplegia who were excluded due to denervation. Of those physically appropriate, psychological factors eliminated several candidates from consideration. Such concerns may also be addressed with suitable intervention in preparation for the clinical application of FNS. Almost 50% of those appropriate for FNS research elected to participate in the programs, with those declining citing the hospitalization, time and travel commitments as the primary factors influencing their decisions. Results suggest that FNS for standing, walking and hand grasp may be an option for a significant percentage of the pediatric SCI population.