Non-gait-specific intervention for the rehabilitation of walking after SCI: role of the arms

Abstract

Arm movements modulate leg activity and improve gait efficiency; however, current rehabilitation interventions focus on improving walking through gait-specific training and do not actively involve the arms. The goal of this project was to assess the effect of a rehabilitation strategy involving simultaneous arm and leg cycling on improving walking after incomplete spinal cord injury (iSCI). We investigated the effect of 1) non-gait-specific training and 2) active arm involvement during training on changes in over ground walking capacity. Participants with iSCI were assigned to simultaneous arm-leg cycling (A&L) or legs only cycling (Leg) training paradigms, and cycling movements were assisted with electrical stimulation. Overground walking speed significantly increased by 0.092 ± 0.022 m/s in the Leg group and 0.27 ± 0.072m/s in the A&L group after training. Whereas the increases in the Leg group were similar to those seen after current locomotor training strategies, increases in the A&L group were significantly larger than those in the Leg group. Walking distance also significantly increased by 32.12 ± 8.74 m in the Leg and 91.58 ± 36.24 m in the A&L group. Muscle strength, sensation, and balance improved in both groups; however, the A&L group had significant improvements in most gait measures and had more regulated joint kinematics and muscle activity after training compared with the Leg group. We conclude that electrical stimulation-assisted cycling training can produce significant improvements in walking after SCI. Furthermore, active arm involvement during training can produce greater improvements in walking performance. This strategy may also be effective in people with other neural disorders or diseases. NEW & NOTEWORTHY This work challenges concepts of task-specific training for the rehabilitation of walking and encourages coordinated training of the arms and legs after spinal cord injury. Cycling of the legs produced significant improvements in walking that were similar in magnitude to those reported with gait-specific training. Moreover, active engagement of the arms simultaneously with the legs generated nearly double the improvements obtained by leg training only. The cervico-lumbar networks are critical for the improvement of walking.

Effect of cervicolumbar coupling on spinal reflexes during cycling after incomplete spinal cord injury

“…Taken collectively, the results of this study demonstrate that the modulation in cervicolumbar coupling reemerges after cycling exercise in people with iSCI. This may partly underlie the significant improvements in overground walking after cycling exercise (Zhou et al 2018). Significantly larger improvements in walking function were found in the A&L group than in the Leg group (Zhou et al 2018).…”

“…In the second part of the project, we assessed the effect of electrical stimulation-assisted cycling training on regulating the modulation of cervicolumbar connectivity in iSCI as well as regulating general spinal excitability to the legs. In a previous study (Zhou et al 2018), we demonstrated that a rehabilitation paradigm involving cycling of the legs results in improvements in overground walking, balance, and sensory and motor scores in people with iSCI. The improvements in walking speed and distance were similar to those reported by conventional rehabilitation interventions for improving ambulation (Zhou et al 2018).…”

“…In a previous study (Zhou et al 2018), we demonstrated that a rehabilitation paradigm involving cycling of the legs results in improvements in overground walking, balance, and sensory and motor scores in people with iSCI. The improvements in walking speed and distance were similar to those reported by conventional rehabilitation interventions for improving ambulation (Zhou et al 2018). We also demonstrated that actively engaging the arms simultaneously with the legs during cycling, may produce even larger improvements in all measured walking metrics.…”

“…This may partly underlie the significant improvements in overground walking after cycling exercise (Zhou et al 2018). Significantly larger improvements in walking function were found in the A&L group than in the Leg group (Zhou et al 2018). Specifically, there was an increase of 0.27 Ϯ 0.072 m/s in 10-m walking and 91.58 Ϯ 36.24 m in 6-min walking distance after 12 wk of training in the A&L group, whereas an increase of 0.092 Ϯ 0.022 m/s in speed and 32.12 Ϯ 8.74 m in distance was seen in the Leg group (Zhou et al 2018).…”

“…The training paradigm was previously described in detail (Zhou et al 2018). Briefly, training took place 1 h/day, 5 days/wk, for 12 wk.…”