Muscle Activation Patterns Estimation during Repeated Wrist Movements from MRI and sEMG*

Functional electrical stimulation (FES) is a widely used method to bypass spinal chord damages and bring the neurological input to muscles. FES methods that allow the activation of both superficial and deep muscles were proposed in the literature. However, even if many studies using surface electromyography (sEMG) for the estimation of muscles’ activation were presented, it still remains impossible to access information of deep muscles. Our group proposed a solution that exploits the morphological information of magnetic resonance imaging (MRI) and the sEMG for the estimation of the average muscles’ activation pattern during isometric muscle contractions of forearm muscles. With this work we introduce the time dimension to study how the activation patterns changes while performing 3 simple wrist movements. The study involved data collected from a single row of electrodes wrapped around the forearm of a single healthy participant. Morphological information are extracted from the MRI to build a model that is then used to estimate the muscles’ activation pattern. The results show that the method is able to provide an estimation of the muscles’ activation patterns that explain more than 93% of the input sEMG information and that have a corresponding in anatomical information from the literature.