Work on urinary incontinence is demonstrating that reconditioning and repairing even more subtle damage in muscle function is within the present bounds of regenerative medicine. Via Medical News Today: "Previous studies in animal models [demonstrated] that injecting stem cells into the urethral muscles increases leak point pressure, leading to the restoration of the deficient muscles. The results of these studies formed the basis for the clinical trial. [Researchers] took biopsies of skeletal muscle tissue from eight female patients and isolated and expanded the stem cells from the tissue in culture. In an outpatient setting, the patients then received injections of the muscle-derived stem cells into the area surrounding the urethra. ... Five of the eight women who participated in the study reported improvement in bladder control and quality of life with no serious short- or long-term adverse effects one year after the initial treatment. ... A multi-center study in Canada and a study in the United States are currently underway and will allow researchers to determine the optimal dose of muscle stem cells."