A Tele-Assessment System for Evaluating Elbow Spasticity in Patients with Neurological Impairments

A portable tele-assessment system was designed for remote evaluation of the elbow joint with spasticity and contracture in patients with neurological disorders. A master device and a slave device were used to drive a manikin arm and the patient´s arm, respectively. The elbow flexion angle and torque were measured at both the master and slave devices, fed back to their counterparts. The examiner moved the manikin arm at selected velocities and haptically felt the resistance from the patient´s elbow to evaluate the spasticity in terms of the velocity dependence of the resistance torque and the catch angle. To minimize the effect of network latency in the tasks with fast speed, a quasi real-time tele-operation scheme was developed which provided the examiner with transparent and stable haptic feeling of the patient´s elbow. The tele-assessment system provided truthful haptic feeling through the internet and allowed us to evaluate the spasticity in elbows of patients post stroke quantitatively.