COBOT – ASSISTED REHABILITATION: REDUCING WORK-RELATED MUSCULOSKELETAL DISORDER (WMSD) RISK ON PHYSIOTHERAPISTS

Recent studies report that 40% to 90% of physiotherapists globally experience WMSDs due to repetitive movements and poor postures during manual rehabilitation therapy. This study aims to evaluate the potential effectiveness of collaborative robot (cobots) in reducing ergonomic risks and preventing WMSDs among physiotherapists. Seven male participants, acting as simulated physiotherapists recruited through convenience sampling performed passive range of motion (PROM) tasks for lower extremity rehabilitation with and without cobot assistance. Full-body motion tracking was carried out with seventeen inertial measurement unit (IMUs) and muscle activation via electromyography (EMG) electrodes. A UR16e cobot was utilized to support the patient’s limbs during rehabilitation exercises, while simultaneously synchronizing biomechanical data collected from a Bertec force plate and motion tracking via an Xsens system. Ergonomic risks were assessed using the REBA tool, and spinal loading was analyzed with the 3D Static Strength Prediction Program (3D SSPP). The Wilcoxon Signed-Rank Test compared cobot-assisted and conventional methods. With cobot assistance, the left biceps brachii activation during hip abduction adduction decreased from 63.95% ± 26.10 %MVIC to 6.09% ± 5.13 %MVIC, while the right erector spinae activation during hip flexion decreased from 54.97% ± 27.82 %MVIC to 8.35% ± 5.03 %MVIC. The REBA score decreased considerably from 8.77 ± 1.50 to 3.68 ± 0.35 during knee flexion and extension tasks. Lumbar compression forces (L5-S1) decreased from 3276.57 ± 109.90 N to 1176.29 ± 40.87 N. All p-values were < 0.05, indicating significant differences between both approaches on all parameters.