OBJECTIVE: To assess the relationship between delays in initiation and termination of tibialis anterior contraction in the hemiplegic lower limb and clinical measures of lower-limb motor impairment and mobility. DESIGN: Cross-sectional correlational study. SETTING: Outpatient rehabilitation clinic of an academic medical center. PARTICIPANTS: Convenience sample of 22 chronic stroke survivors with lower-limb hemiparesis. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Delays in initiation and termination of tibialis anterior electromyographic activity during isometric contraction, lower-limb Fugl-Meyer Assessment (FMA), and Modified Emory Functional Ambulation Profile (mEFAP). RESULTS: The affected lower limb exhibited significantly longer delays in initiation and termination of tibialis anterior contraction relative to the unaffected limb. Delay in termination of 3-second tibialis anterior contraction of the affected limb correlated significantly with the FMA and mEFAP. However, delay in initiation of tibialis anterior contraction did not correlate with clinical measures. CONCLUSIONS: Delay in termination of muscle activity in the hemiparetic lower limb may have important clinical implications, but delay in initiation did not correlate with clinical measures. Controlled, interventional trials are needed to demonstrate a cause and effect relationship.
OBJECTIVE: To assess the relationship between delays in initiation and termination of tibialis anterior contraction in the hemiplegic lower limb and clinical measures of lower-limb motor impairment and mobility. DESIGN: Cross-sectional correlational study. SETTING:Outpatient rehabilitation clinic of an academic medical center. PARTICIPANTS: Convenience sample of 22 chronic stroke survivors with lower-limb hemiparesis. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Delays in initiation and termination of tibialis anterior electromyographic activity during isometric contraction, lower-limb Fugl-Meyer Assessment (FMA), and Modified Emory Functional Ambulation Profile (mEFAP). RESULTS: The affected lower limb exhibited significantly longer delays in initiation and termination of tibialis anterior contraction relative to the unaffected limb. Delay in termination of 3-second tibialis anterior contraction of the affected limb correlated significantly with the FMA and mEFAP. However, delay in initiation of tibialis anterior contraction did not correlate with clinical measures. CONCLUSIONS: Delay in termination of muscle activity in the hemiparetic lower limb may have important clinical implications, but delay in initiation did not correlate with clinical measures. Controlled, interventional trials are needed to demonstrate a cause and effect relationship.