Bilateral Arm Training vs Unilateral Arm Training for Severely Affected Patients With Stroke: Exploratory Single-Blinded Randomized Controlled Trial

To compare the effects of unilateral and bilateral arm training on arm impairment in severely affected patients with stroke. Single-blinded, randomized controlled trial. Inpatient rehabilitation center. First-time subacute patients (N=69) with stroke and a nonfunctional hand. Patients were stratified according to lesion location post hoc. Repetitive bilateral arm training on an arm cycle followed by synchronized bilateral repetitive distal hand training or an identical unilateral arm training performed by the paretic limb only. Both unilateral and bilateral trainings were administered twice daily over 6 weeks. The primary outcome measure was the Fugl-Meyer Assessment (FMA) score for the arm, and secondary measures were biomechanical parameters measuring isometric force and rate of force generation. Outcome measures were assessed before, at the end of, and 2 weeks after intervention. Patients were homogeneous at study onset. All patients improved regarding the FMA arm score and most biomechanical parameters after intervention. Yet the post hoc analysis stratifying patients according to lesion location showed that patients with pure subcortical stroke, but not patients with cortical involvement of stroke, showed a significantly greater improvement (P=.022) following the bilateral training in FMA arm score (from 6.8±5.7 to 17.8±15.8) compared with unilateral training (from 6.5±7.8 to 8.7±8.6). The benefit of bilateral arm training followed by repetitive bilateral hand training for motor control of the severely paretic upper limb may depend on lesion location. Further studies with larger sample size are required for the validation of these results.