Clinical Tests for Detecting Synergy Movements and Clinical Understanding of Stroke Patients Using PLEMO System with Sensor Grip Device

Abstract

We have developed PLEMO to assist hemiplegic stroke patients in upper-limb rehabilitation using a passive haptic device with electrorheological (ER) fluid brakes. The PLEMO has no moving parts, ensuring safe rehabilitation assistance in the clinical setting. The previously reported version of the PLEMO can determine the operating force and the displacement of the grip by using conventional sensor devices; however, it was not enough to provide information evaluating stroke patient motor function. To cover such shortcomings of the conventional systems, we developed a new grip and motor-functional evaluation software that detects synergy, a symptomatic feature in stroke patients. In clinical evaluation of 14 stroke patients - two Brunnstrom Recovery Stage III, three Stage IV, and nine Stage V - we studied the correlation between PLEMO evaluation and rehabilitation evaluation, and found a strong correlation between them, e.g., changes in wrist movement range and table-reaction force provided useful information on stroke severity.