Vaginal Surgery for the Pelvic Floor: A Randomized Trial of Synthetic Mesh Versus Synthetic Sutures

Background and Rationale:

The pelvic floor comprises muscles, nerves and a fascial network with dynamic, elastic ligaments of support. Pelvic organ prolapse (POP) occurs when the capacity to accommodate pressure and stretch is exceeded and increases with childbirth and aging. One in five women need surgery for POP. POP suspension performed vaginally is among the most important ideas in gynecology in the past few decades, however the investigators do not know which technique is best. The principal applicant has developed a novel surgery: bilateral sacrospinous vaginal vault fixation with synthetic mesh arms (BSSVF-M), which may be more successful, durable and cost-effective than standard sacrospinous ligament suspension with sutures (SSLS) and may thus become the preferred vaginal POP surgery both nationally and internationally. A Cochrane review on surgical management of POP concluded that "adequately powered RCTs with blinding of assessors are urgently needed [...] they particularly need to include women's perceptions." The OPTIMAL trial, a large RCT comparing 2 POP surgeries, established a stringent definition of success using a composite outcome of objectively measured POP, subjective improvement and the need for another treatment for POP recurrence.

Identifying the best way to surgically suspend the vagina for POP can make the difference between a woman who can enjoy a desired level of physical activity at work or play, empty her bowel and bladder without concerns, engage in a normal sexual life and a woman who can't perform these basic activities without discomfort, pain, worry and shame. The vaginal approach for pelvic surgery offers less pain, a shorter hospital stay, a faster recovery and no external incisions. However, what is the safest, most durable, most cost-effective vaginal POP surgery? Prior operations have produced unacceptable complications or a need for reoperation for POP recurrence. Further suffering for women and unacceptable healthcare costs ensued. Because seniors (over age 65) are the fastest growing age group in Canada, the CIHR states research into aging should be prioritized. By 2031, Statistics Canada estimates the number of senior women to reach 5.1 million or 24% of the total female population. Women have longer life expectancy than men. The burden of POP increases with age; 1 of 2 women over 80 experience pelvic floor dysfunction. For some aging women, vaginal surgery is the only option because of comorbidities precluding more invasive or lengthier open abdominal surgeries. Currently, there is true clinical equipoise between BSSVF-M and SSLS. Our novel mesh insertion technique, BSSVF-M, offers the advantages of small size, deep, tension-free and tailored to individual anatomy. This ensures midline restoration of the vaginal axis and maintains flexibility for normal bladder, bowel and sexual function. Tension-free insertion of BSSVF-M is a key difference with SSLS, which pulls the vagina tight against ligaments, causing pain or the return of POP after SSLS. Surgical innovation is important but adoption of new procedures needs reliable evidence acquired through a rigorous Innovation, Development, Exploration, Assessment, Long-term study (IDEAL) paradigm.

The investigators have been studying BSSVF-M over the past 9 years. Initial development included a magnetic resonance imaging study establishing restoration of pelvic anatomy comparable to normal. An exploratory prospective cohort study followed, showing BSSVF-M to be safe, easily taught to other surgeons and successful in 77% of women at one year, with the OPTIMAL composite outcome. This is superior to the reported 60% success of the SSLS and informed our power calculation for the proposed RCT. An informal survey of 50 Western Society for Pelvic Medicine surgeons indicated that an average of 14% increase in composite outcome success would be sufficient to adopt a new vaginal suspension technique. The investigators are now at the IDEAL assessment stage, where our novel technique warrants an RCT before widespread adoption. The results of this trial will directly inform surgeons whether mesh should be used for vaginal repair of POP and how to counsel patients. This trial includes knowledge translation for women to understand pelvic floor symptoms, related condition-specific quality of life, sexual health and body image after two vaginal surgery procedures. A rigorous cost effectiveness analysis will inform different stakeholders and policy makers regarding cost effectiveness.

Primary Objective: