Time Course of Functional and Biomechanical Improvements During a Gait Training Intervention in Persons With Chronic Stroke

Abstract

Background and Purpose In rehabilitation, examining how variables change over time can help to define the minimal number of training sessions required to produce a desired change. The purpose of this study was to identify the time course of changes in gait biomechanics and walking function in persons with chronic stroke. Methods Thirteen persons > 6 months post-stroke participated in 12 weeks of fast treadmill training combined with plantar- and dorsi-flexor muscle functional electrical stimulation (FastFES). All participants completed testing before the start of intervention, after 4, 8 and 12 weeks of FastFES locomotor training. Results Peak limb paretic propulsion, paretic limb propulsive integral, peak paretic limb knee flexion, (p<0.05 for all) and peak paretic trailing limb angle (p<0.01) improved from pre-training to 4 weeks but not between 4 and 12 weeks. Self-selected walking speed and 6-minute walk test distance improved from pre-training to 4 weeks and from 4 to 12 weeks (p<0.01 and p<0.05, respectively for both). Timed Up & Go test time did not improve between pre-training and 4 weeks, but improved by 12 weeks (p=0.24 and p<0.01, respectively). Discussion and Conclusions The results demonstrate that walking function improves with a different time course compared to gait biomechanics in response to a locomotor training intervention in persons with chronic stroke. Thirty-six training sessions were necessary to achieve an increase in walking speed that exceeded the MCID. These finding should be considered when designing locomotor training interventions after stroke. Video Abstract available (see Video, Supplemental Digital Content 1) for more insights from the authors.

Mechanisms used to increase peak propulsive force following 12-weeks of gait training in individuals poststroke

“…Self-selected walking speed was defined as the participant’s comfortable overground walking speed during a 10-m walk test. Previous work has provided detailed description for the gait analysis setup (Awad et al, 2014; Kesar et al, 2014; Reisman et al, 2013). Participants wore an overhead harness system for safety and were allowed to use the handrails if they normally utilized an assistive device (i.e., a cane) or if they felt unsafe walking on a treadmill.…”

“…Rest breaks of up to 5 minutes were provided between walking bouts. More detail on the FastFES intervention may be found in previous work from our laboratory (Awad et al, 2014; Reisman et al, 2013). …”

Targeting Paretic Propulsion to Improve Poststroke Walking Function: A Preliminary Study

“…Previous work has described in detail the methods used during this investigation 32,33 . Briefly, kinetic and kinematic data were collected via an 8-camera motion analysis system a as subjects walked at their self-selected speeds on a dual-belt treadmill instrumented with two independent 6 degree of freedom force platforms b .…”

“…During all periods of walking without FES, subjects were encouraged to reproduce the same walking pattern as practiced with the FES. The training protocol used has previously been described 32,33 .…”

“…Details regarding the customized FES system c used and the methods employed can be found in previous studies put forth by our laboratory 29,32,33,39,40 . FES was delivered to the ankle dorsiflexor and plantarflexor muscles during walking through self-adhesive surface electrical stimulation electrodes d,e .…”