Abstract
The Lower Urinary Tract (LUT) stores and evacuates urine. Its neural control is complex and its mechanisms are scarcely described. Among patients with Spinal Cord Injury (SCI) two deficiencies with respect to bladder control are common : detrusor over-activity (DOA) and detrusor-sphincter dyssynergia. Functional Electrical Stimulation (FES) can be used to counteract DOA and artificially manage the bladder. However it requires a better understanding of the system and to be able to activate selectively the detrusor and the striated sphincter. The contribution of this thesis can be divided in three parts : the development of a LUT model particularly focused on the detrusor, the experimental validation of this model, and finally the study of the recruitment in selective multi-polar electrical stimulation. The LUT model proposed here takes into account the specificity of the smooth muscle (the detrusor). It is a multi-scale model. It describes the system from the biochemical reactions of the muscle activation to the macroscopical physics at the global scale of the bladder+sphincter system. A study of model sensitivity with respect to its main parameters was conducted using a numerical implementation. Identification and validation of the referred model was performed based on animal experiments in isometric condition. Finally, we set up a toolchain to simulate selective multi-polar electrical stimulation and inverse recruitment techniques. Simulations results are presented and an experimental protocol to evaluate functionally these methods on animal model is proposed.