Urinary incontinence, the involuntary loss of urine, still remains a mayor medical issue with approximately 20% of women affected. The quality of life of patients with urinary incontinence is severely affected. The main cause for urinary incontinence is damage of the sphincter muscle, which occurs during childbirth, surgical treatments or as an effect of aging. Current surgical treatment options enable recovery of continence with various outcomes. However, definitive correction of underlying etiology, the damages muscle, has not been accomplished. Furthermore, these options only offer short-term relief and the overall success of these therapies are limited by complications.Recently, we were able to demonstrate the effectiveness of using muscle cells in the treatment of sphincter insufficiency in a large animal model. A small biopsy of a leg muscle was taken and the cells expanded in the laboratory. These cells were then injected into the damages sphincter muscle. Our results showed that injected muscle cells were able to form new sphincter muscle and achieve 80% of sphincter function after 6 months.The approach used was chosen due to the simple procedure needed for the functional restoration of the urinary sphincter. The rationale for implanting muscle into the damaged sphincter muscle is two-fold. First, the generation of a muscle tissue mass will achieve a volume effect that would increase the sphincter pressure, thus controlling incontinence. Second, implantation of muscle cells will achieve restoration of sphincter function through the formation of new nerves, which control continence over time. If successful this would clearly demonstrate a major medical breakthrough. Our research is structured into different steps. First, we will adapt the methods used to handle animal muscle cells to human tissues. Second, we will investigate the optimal method for cell injection in humans using magnet resonance imaging (MRI) and ultrasound (US). Third, we will design and conduct the first human trials in Switzerland.