Investigation of controllable multi electrode based FES (functional electrical stimulation) system for restoration of grasp-preliminary study on healthy individuals

Functional electrical stimulation applied via surface electrode can be used for hand rehabilitation particularly for enabling grasp in patients with stroke or spinal cord injury. The use of multi-pad electrode and multi-channel electrical stimulator based improve the effectiveness of conventional FES. Such a system consists of a multi-pad surface electrode and a matching multi-channel stimulator. This system will allow the targeting of motor neurons which activate muscle groups to produce corresponding functional movements of the hand. This paper presents our study on normal subjects to quantify the movement resulting from stimulation of electrodes spatially distributed around the forearm. The device was tested on four healthy subjects and the results show that multi-pad electrode provide desired amount of selectivity and can be used for generating functional grasp. The results also show that the effect of stimulation varies from person to person reflecting inters subject anatomical variability.