Article

OBJECTIVES: To investigate the effect of walking speed on the emergence of
locomotor electromyogram (EMG) patterns in an individual with chronic incomplete
spinal cord injury (SCI), and to determine whether central pattern generator
activity during robotic locomotor training (RLT) transfers to volitional EMG
activity during overground walking. DESIGN: Single-case (B-A-B; experimental
treatment-withdrawal-experimental treatment) design. SETTING: Freestanding
rehabilitation research center. PARTICIPANT: A 50-year-old man who was
nonambulatory for 16 months after incomplete SCI (sub-T11). INTERVENTIONS: The
participant completed two 6-week blocks of RLT, training 4 times per week for 30
minutes per session at walking speeds up to 5km/h (1.4m/s) over continuous bouts
lasting up to 17 minutes. MAIN OUTCOME MEASURES: Surface EMG was recorded weekly
during RLT and overground walking. The Walking Index for Spinal Cord Injury
(WISCI-II) was assessed daily during training blocks. RESULTS: During week 4,
reciprocal, patterned EMG emerged during RLT. EMG amplitude modulation revealed a
curvilinear relationship over the range of walking speeds from 1.5 to 5km/h
(1.4m/s). Functionally, the participant improved from being nonambulatory
(WISCI-II 1/20), to walking overground with reciprocal stepping using
knee-ankle-foot orthoses and a walker (WISCI-II 9/20). EMG was also observed
during overground walking. These functional gains were maintained greater than 4
years after locomotor training (LT). CONCLUSIONS: Here we report an unexpected
course of locomotor recovery in an individual with chronic incomplete SCI.
Through RLT at physiologic walking speeds, it was possible to activate the
central pattern generator even 16 months postinjury. Further, to a certain
degree, improvements from RLT transferred to overground walking. Our results
suggest that LT-induced changes affect the central pattern generator and allow
supraspinal inputs to engage residual spinal pathways.
CI - Copyright (c) 2012 American Congress of Rehabilitation Medicine. Published by
Elsevier Inc. All rights reserved.

Langue : ANGLAIS