title: Constraining upper limb synergies of hemiparetic patients using a robotic exoskeleton in the perspective of neuro-rehabilitation.
abstract: The aim of this paper was to explore how an upper limb exoskeleton can be programmed to impose specific joint coordination patterns during rehabilitation. Based on rationale which emphasizes the importance of the quality of movement coordination in the motor relearning process, a robot controller was developed with the aim of reproducing the individual corrections imposed by a physical therapist on a hemiparetic patient during pointing movements. The approach exploits a description of the joint synergies using principal component analysis (PCA) on joint velocities. This mathematical tool is used both to characterize the patient's movements, with or without the assistance of a physical therapist, and to program the exoskeleton during active-assisted exercises. An original feature of this controller is that the hand trajectory is not imposed on the patient: only the coordination law is modified. Experiments with hemiparetic patients using this new active-assisted mode were conducted. Obtained results demonstrate that the desired inter-joint coordination was successfully enforced, without significantly modifying the trajectory of the end point.
authors.affiliation: UPMC University, Paris 06, UMR 7222, ISIR-CNRS, F-75005 Paris, France. crocher@isir.fr
authors.forename: Vincent
authors.initials: V
authors.lastname: Crocher
authors.forename: Anis
authors.initials: A
authors.lastname: Sahbani
authors.forename: Johanna
authors.initials: J
authors.lastname: Robertson
authors.forename: Agnès
authors.initials: A
authors.lastname: Roby-Brami
authors.forename: Guillaume
authors.initials: G
authors.lastname: Morel
mesh_terms: D000328:Adult; D000368:Aged; D000465:Algorithms; D001696:Biomechanical Phenomena; D001925:Brain Damage, Chronic / Q000534:rehabilitation; D002545:Brain Ischemia / Q000150:complications / Q000534:rehabilitation; D002543:Cerebral Hemorrhage / Q000150:complications / Q000534:rehabilitation; D003627:Data Interpretation, Statistical; D005260:Female; D006225:Hand / Q000502:physiology; D006801:Humans; D007596:Joints / Q000502:physiology; D007858:Learning / Q000502:physiology; D008297:Male; D008875:Middle Aged; D009048:Motor Skills / Q000502:physiology; D009473:Neuronal Plasticity / Q000502:physiology; D010291:Paresis / Q000209:etiology / Q000534:rehabilitation*; D025341:Principal Component Analysis; D011597:Psychomotor Performance / Q000502:physiology; D012371:Robotics / Q000379:methods*; D020521:Stroke / Q000209:etiology; D000071939:Stroke Rehabilitation; D019415:Torque; D034941:Upper Extremity / Q000502:physiology*