Motor impairment as a predictor of functional recovery and guide to rehabilitation treatment after stroke

Abstract

Objective: This study tests three hypotheses relevant for the efficient use of rehabilitation services after stroke: (a) the severity of initial motor impairment after stroke predicts discharge motor impairment and self-care mobility scores; (b) identification of those unlikely to show improvement in motor impairment can focus rehabilitzation efforts on use of compensatory techniques and assist devices; and (c) improvement in self-care mobility scores without change in motor impairment, balance, or cognition is a quantitative estimate of the value of teaching compensatory techniques and use of assist devices.

Methods: We studied 171 sequential patients previously independent in the community who were admitted for inpatient rehabilitation within 17 +/- 12 SD days of an initial, unilateral, hemispheric, ischemic stroke. Impairment was assessed using the Fugl-Meyer upper limb motor (ULM), lower limb motor (LLM), and upper plus lower limb total motor (TM) subscores. Disability was assessed using the Functional Independence Measure (FIM), FIM self-care (FIMS), FIM mobility (FIMM), and FIM self-care plus FIM mobility (FIMSM) subscores. Spearman correlation coefficients tested strength of association between dependent and independent variables, stepwise linear regression tested the effects of clinically relevant co-variables, and positive and negative predictive values (PPV, NPV) assessed the clinical relevance of outcome-prediction models.

Results: The highest correlations observed were between admission TM scores and the following discharge scores: TM (R = 0.92; p < 0.01), ULM (R = 0.91; p < 0.01), LLM (R = 0.82; p < 0.01), FIMSM (R = 0.67; p < 0.01), FIMM (R = 0.67; p < 0.001), FIM (R = 0.58; p < 0.0001). An admission TM score in the lowest quartile had a PPV of 0.74 for a discharge ULM score in the lowest quartile. An admission TM score in the highest quartile had a PPV of 0.86 for a discharge ULM score in the highest quartile. Similar but weaker PPVs were seen for admission TM scores and discharge LLM scores. Patients without significant change in TM scores (< or = 2 points) had a 17 +/- 9 SD improvement in FIMSM scores.

Conclusions: Admission motor impairment scores (a) predict discharge impairment and activities of daily living mobility functional outcome; and (b) guide treatment toward improving motor impairment versus use of compensatory techniques and assistive devices. The use of compensatory techniques and assistive devices, without change in motor impairment, is associated with a 17 +/- 9 SD improvement in FIMSM score.