High intensity variable stepping training in persons with motor incomplete spinal cord injury: a case series

Abstract

Background and Purpose: Previous data suggest that large amounts of high intensity stepping training in variable contexts (tasks and environments) may improve locomotor function, aerobic capacity and treadmill gait kinematics in individuals post-stroke. Whether similar training strategies are tolerated and efficacious for patients with other acute-onset neurological diagnoses, such as motor incomplete spinal cord injury (iSCI) is unknown, particularly with potentially greater, bilateral impairments. This case series evaluated the feasibility and preliminary short and long-term efficacy of high intensity variable stepping practice in ambulatory participants >1 year post-iSCI. Case Series Description: Four participants with iSCI (neurological levels C5-T3) completed up to 40 1-hr sessions over 3–4 months. Stepping training in variable contexts was performed at up to 85% maximum predicted heart rate, with feasibility measures of patient tolerance, total steps/session, and intensity of training. Clinical measures of locomotor function, balance, peak metabolic capacity and gait kinematics during graded treadmill assessments were performed at baseline and post-training, with >1 year follow-up. Outcomes: Participants completed 24–40 sessions over 8–15 weeks, averaging 2222±653 steps/session, with primary adverse events of fatigue and muscle soreness. Modest improvements in locomotor capacity where observed at post-training, with variable changes in lower extremity kinematics during treadmill walking. Discussion: High intensity, variable stepping training was feasible and tolerated by participants with iSCI although only modest gains in gait function or quality were observed. The utility of this intervention in patients with more profound impairments may be limited.