Intense Arm Rehabilitation Therapy Improves the Modified Rankin Scale Score: Association Between Gains in Impairment and Function.

OBJECTIVE:To evaluate the effect of intensive rehabilitation on the modified Rankin Scale (mRS), a measure of activities limitation commonly used in acute stroke studies, and to define the specific changes in body structure/function (motor impairment) most related to mRS gains. METHODS:Patients were enrolled >90 days poststroke. Each was evaluated before and 30 days after a 6-week course of daily rehabilitation targeting the arm. Activity gains, measured using the mRS, were examined and compared to body structure/function gains, measured using the Fugl-Meyer (FM) motor scale. Additional analyses examined whether activity gains were more strongly related to specific body structure/function gains. RESULTS:At baseline (160 ± 48 days poststroke), patients (n = 77) had median mRS score of 3 (interquartile range, 2-3), decreasing to 2 [2-3] 30 days posttherapy (p < 0.0001). Similarly, the proportion of patients with mRS score ≤2 increased from 46.8% at baseline to 66.2% at 30 days posttherapy (p = 0.015). These findings were accounted for by the mRS score decreasing in 24 (31.2%) patients. Patients with a treatment-related mRS score improvement, compared to those without, had similar overall motor gains (change in total FM score, p = 0.63). In exploratory analysis, improvement in several specific motor impairments, such as finger flexion and wrist circumduction, was significantly associated with higher likelihood of mRS decrease. CONCLUSIONS:Intensive arm motor therapy is associated with improved mRS in a substantial fraction (31.2%) of patients. Exploratory analysis suggests specific motor impairments that might underlie this finding and may be optimal targets for rehabilitation therapies that aim to reduce activities limitations. CLINICAL TRIAL:Clinicaltrials.gov identifier: NCT02360488. CLASSIFICATION OF EVIDENCE:This study provides Class III evidence that for patients >90 days poststroke with persistent arm motor deficits, intensive arm motor therapy improved mRS in a substantial fraction (31.2%) of patients.