Analyse des forces des membres supérieurs développées par des participants hémiparétiques dans un entrainement bimanuel

Abstract

Introduction : The balance of pushing forces in the upper limbs is upset due to a stroke. The introduction of force control therapy in strokes’ rehabilitation trainings could be one avenue for hemiparetic patients to regain bimanual symmetry of forces between the two arms. Objective : The main purpose of this project is to investigate the reaction force patterns on a robotic bimanual exerciser during bimanual push exercises and determine whether there are significant differences in force production between hemiparetic and healthy participants. Method : Force data from nineteen healthy and seventeen stroke subjects were collected at 600 Hz during manual thrust training with resistances of 15% and 30% of maximum voluntary force. The analysis of the curves made it possible to characterize a transitional regime and a steady state. Three dependent parameters during the transitional regime were measured: thrust time, the first overshoot and the time gap between upper limb departures. Three dependent parameters were studied for the steady state: the subject's ability to respect the ± 2% set point called stability, the coefficient of variation of the force and the regularity of the signal fluctuations called approximate entropy. Results : There is no difference between the metrics of the transient regime and the approximate entropy of healthy and pathological patients. But there are significant differences between healthy and pathological patients for the steady-state metrics. On the non dominant side, stability is greater for healthy subjects, 29. 1% ± 8. 5 to 15%, compared to 23. 7% ± 5. 5 for hemiparetic subjects. Conversely, the coefficient of variation is lower for the healthy group, 31. 3% ± 8. 7 to 15% compared to the pathological group, 40. 1% ± 11. 7 to 15%. These results indicate that the pathological group has a greater deviation of the force from the setpoint required and therefore a greater decrease in precision. Conclusions : There is a difference in strength in the steady state. The steady state corresponds to the moment when the participants move the handles while maintaining a constant force. Significant differences were observed for stability and coefficient of variation in strength between healthy and hemiparetic subjects. These variables are characteristic of participants' ability to aim at the set point and not to move away from it when moving the handles. Thus, there is a decrease in stroke-related force control.

Date	21 Mar 2021
Original language	French
Awarding Institution	École de technologie supérieure
Supervisor	Rachid Aissaoui (Supervisor)