Scientists at the University of Sheffield have developed a new implantable material, which has the potential to reduce complications for women suffering from urinary incontinence. Extremely rigid materials, which are used to treat urinary incontinence, can cause adverse side-effects.
Stress urinary incontinence is a medical condition, where pressure on the bladder caused by laughing, sneezing, or exercise, and often due to the menopause, surgery or childbirth, results in urine leakage. It has been estimated that about 3 to 6 million people in the UK suffer from some form of urinary incontinence.
The study results have been reported both in the Journal of Urology and the PLOS ONE journal. They provide sufficient proof that a material that is soft and flexible can be used to support the urethra. A recent study has highlighted the long-term effect of vaginal childbirth delivery. Such procedures can double the risk of stress urinary incontinence.
Existing treatments involve the use of a stiff woven polypropylene mesh device, which is implanted beneath the urethra to repair weakened or damaged tissues. The material used in the polypropylene mesh device was actually developed for hernia repairs, but this was repurposed in the mid-1990s for surgical treatment of urinary incontinence. This practice is now being followed worldwide.
Most women who suffer from urinary incontinence opt for surgery. In fact, the NHS performs about 13,500 operations every year to treat such conditions, including pelvic organ prolapse. Over the past decade the use of the current material has caused complications in many patients following stress urinary incontinence surgery. It has been estimated that about 15% of women can develop serious complications such as infection, chronic pain, or erosion or failure of the implant.
In collaboration with international collaborators in Europe, Sheffield's Centre for Biomaterials and Tissue Engineering Group has developed a new implantable device with elastic polyurethane. This flexible polyurethane simulates the natural recoil of a normal pelvic floor.
In younger women, the organs of the pelvis have a strong and elastic pelvic floor, supported by a combination of connective tissue, muscles and ligaments that provide 'a well-sprung floor', much like a trampoline. Unfortunately, one of the consequences of pregnancy is that there is often damage and weakening to the tissues of the pelvic floor, as it becomes further stretched, with a resulting loss of elasticity. After 6 years of product development and pre-clinical testing, the elastic polyurethane material we have rigorously tested is neither too strong nor too brittle, it does not weaken over time and aims to avoid the complications that currently occur with using polypropylene mesh.
Professor Sheila MacNeil, Department of Materials Science and Engineering, University of Sheffield
The device has been tested by implanting in physiologically pertinent animal models via a European collaboration with colleague Professor Jan Deprest in Leuven. This is a major aspect of pre-clinical studies, to discover if the implanted material is indeed compatible or not. This also underlines the fact that the new device is suitably integrated into the tissues and causes relatively less inflammatory reactions, compared to the existing polypropylene mesh device. Sheffield’s study could set the stage for clinical testing of this device and end the pain and complications experienced by thousands of patients across the globe.