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

Abstract

OBJECTIVE To determine 1) the feasibility and safety of implementing a 12-week locomotor intervention targeting paretic propulsion deficits during walking through the joining of two independent interventions: walking at maximal speed on a treadmill and functional electrical stimulation of the paretic ankle musculature (FastFES), 2) the effects of FastFES training on individual subjects, and 3) the influence of baseline impairment severity on treatment outcomes. DESIGN A single group pre-post preliminary study investigating a novel locomotor intervention. Changes following treatment were assessed using pair-wise comparisons and compared to known minimal clinically important differences (MCIDs) or minimal detectable changes (MDCs). Correlation analyses were run to determine the relationship between baseline clinical and biomechanical performance versus improvements in walking speed. SETTING University clinical research laboratory. PARTICIPANTS Thirteen individuals with locomotor deficits following a stroke. INTERVENTION FastFES training was provided for 12 weeks at a frequency of 3 sessions per week and 30 minutes per session. MAIN OUTCOME MEASURES Measures of gait mechanics, functional balance, short- and long-distance walking function, and self-perceived participation were collected at baseline, post-training, and at a 3 month follow-up. RESULTS Twelve of the 13 subjects recruited completed training. Improvements in paretic propulsion were accompanied by improvements in functional balance, walking function, and self-perceived participation (each p < 0.02) – all of which were maintained at the 3 month follow up. Eleven of the 12 subjects achieved meaningful functional improvements. Baseline impairment was predictive of absolute, but not relative functional change following training. CONCLUSIONS This report demonstrates the safety and feasibility of the FastFES intervention and supports further study of this promising locomotor intervention for persons post-stroke.

Symmetry of corticomotor input to plantarflexors influences the propulsive strategy used to increase walking speed post-stroke

“…Participants performed a 10-meter walk test to quantify self-selected and fastest walking speeds (Awad et al 2014). An average of 3 tests for each speed was used.…”

“…Knowledge of an individual’s paretic plantarflexor contribution to forward propulsion can distinguish him or her between functional ambulation classifications of limited versus unlimited community ambulators (Bowden et al 2008; Peterson et al 2010). Further, rehabilitation strategies that improved paretic limb propulsion have also improved post-stroke walking function (Awad et al 2014; Bowden et al 2013). The two main contributors to forward propulsion are trailing limb angle and ankle plantarflexion moment (Hsiao et al 2015a; Hsiao et al 2015b).…”

A soft robotic exosuit improves walking in patients after stroke

“…Peak PP, interlimb propulsion symmetry, peak paretic limb swing phase ankle DF angle, and mass-and speed-normalized energy consumption served as dependent variables because of their popularity and importance in the poststroke gait rehabilitation literature (2,22,25,49,50,55,57,63,65,86,93,94). All analyses were directed toward evaluating the exosuit's influence on poststroke gait.…”

“…GRFs were used to compute PP and non-PP and this study's primary kinetic outcome: interlimb propulsion symmetry. PP was defined as the anterior GRF measured during the paretic limb's stance phase, normalized by body weight (% bw) (65,79,86,(89)(90)(91).…”

Plantar pressure displacement after anesthetic motor block and tibial nerve neurotomy in spastic equinovarus foot

“…More specifically, the AP displacement of the trajectory of the COP, which has been shown to have good repeatability [17], was significantly improved following motor nerve block and selective neurotomy in the present study. These quantified parameters could be compared or used in addition to other quantitative measures of gait recovery used in hemiparesis like walking speed, percentage of time spent in double and single limb support, stance, and swing phases [19][20][21]. Motor nerve block of the tibial nerve branches is predictive of the results of selective tibial neurotomy [22][23].…”