Robot-assisted Treatment Contributes to Regaining Upper Limb Motility in Stroke Patients:a Randomized-controlled Trial Based on Functional Near Infrared Spectroscopy

Abstract Background Robot-assisted treatment(RAT) has drawn a lot of interest in stroke motor rehabilitation. Theoretically, the best protocol for a patient should be selected based on features of the brain's functional reactions associated with RAT. However, due to a paucity of techniques for dynamic brain functional testing, the cortical reaction response to RAT has yet to be thoroughly understood. Objective This study concentrated on the treatment effect and brain functional responses to RAT obtained with functional near infrared spectroscopy (fNIRS) in individuals having experienced a stroke with upper limb mobility impairment to direct the application of clinical therapy. Methods Eighteen stroke patients were randomly distributed to the robotics group (RG) to receive RAT and the control group (CG) to receive motor training without robot-assistance. Therapies were administered five days per week, for one month, and the outcome indicators were assessed at baseline and 30 days after treatment onset. The clinical evaluations included administration of the Fugl-Meyer assessment for upper-extremity(FMA-UE), action research arm test(ARAT), together with fNIRS recordings.The relative variations in oxyhemoglobin (OxyHb) concentrations measured by fNIRS were used to determine cortical activity levels. Results After four weeks of rehabilitation training, the FMA-UE and ARAT points of both groups considerably increased. The FMA-UE and ARAT points of the RG improved more than those of the CG. In comparison to the CG, fNIRS recordings showed enhanced cortical activation of the primary motor cortex in the ipsilateral hemisphere (i-M1) in the RG. Correlation analysis demonstrated a significant positive correlation between FMA-UE points improvements and therapy-evoked increases in the OxyHb of i-M1 in both the RG(r = 0.88, p < 0.001) and CG (r = 0.71, p = 0.03).It also showed a substantial positive association of the ARAT score changes and therapy-evoked increases in the OxyHb of M1 in the RG (r = 0.92, p < 0.001) and CG(r = 0.87, p < 0.002). Conclusion Our findings suggest that RAT performed as well or better than classic therapy methods that could help patients with stroke with upper extremity motor dysfunction and activate M1. This activation may promote reorganization of brain function. Trial registration ChiCTR, ChiCTR1800019783. Registered 28 November 2018, https://www.chictr.org.cn/ ChiCTR1800019783