Effect of cross education using robotic rehabilitation on upper extremity motor function and strength in stroke patients

Motor dysfunction in the upper extremities (UE) after stroke limits individuals' activity levels. Although traditional rehabilitation often focuses on the contralesional UE, innovative approaches such as cross education have gained prominence in recent years. The aim of this study is to investigate the effect of cross education using robotic rehabilitation (RR) on UE motor function and strength in patients with stroke. Twenty-two stroke patients included in the study were randomly assigned to the Cross Education Group (CEG) and the Control Group (CG). The participants underwent a physiotherapy training program 5 days a week for 5 weeks. In this program, conventional rehabilitation was administered 3 days a week for 45 minutes, and RR was applied to the more affected side UE 2 days a week for 40 minutes. In addition, prior to each RR session, both groups underwent a 20-minute intervention twice weekly: the CEG received cross education training on the less affected UE using RR, whereas the CG performed lower extremity exercises. Clinical measurements were conducted before and after the intervention. Motor function was evaluated using the Fugl-Meyer Assessment for the Upper Extremity (FM-UE), the Action Research Arm Test (ARAT), and the Box and Block Test (BBT); strength was assessed through measurements of hand grip strength and isometric elbow flexion and extension strength; activities of daily living were evaluated using the Modified Barthel Index (MBI), and quality of life was assessed using the Stroke Impact Scale (SIS). After the intervention, within-group analyses revealed significant improvements in the CEG in the FM-UE total score (p<0.001), FM-UE proximal (p<0.001) and distal (p=0.011) subscores, ARAT (p=0.005), BBT (p=0.011), hand grip strength (p=0.034; p=0.007) and isometric elbow flexion strength (p=0.047; p=0.001) on both the less and more affected sides, isometric elbow extension strength on the more affected side (p=0.008), MBI (p=0.017), and SIS (p<0.05). In the CG, significant improvements were found in FM-UE total score (p<0.001), FM-UE proximal subscore (p<0.001), ARAT (p=0.017), BBT (p=0.018), hand grip strength (p=0.013) and isometric elbow extension strength (p=0.002) on the more affected side, and isometric elbow flexion strength on both the less and more affected sides (p=0.024; p<0.001), MBI (p=0.021), and SIS (p<0.05). In between group comparisons, a significant difference in favor of the CEG was found only in the FM-UE proximal subscore (p=0.040). The findings suggest that cross education using RR may serve as an alternative strategy to rehabilitation programs for improving proximal UE motor functions in stroke.