Multicenter prospective randomized study of single-incision mini-sling vs tension-free vaginal tape-obturator in management of female stress urinary incontinence: a minimum of 1-year follow-up

Objective To compare an adjustable anchored single incision mini-sling (SIMS-Ajust) vs tension-free vaginal tape-obturator (TVT-O) in the management of female stress urinary incontinence (SUI) with a minimum of 1-year follow-up. Methods We conducted a multicenter prospective randomized control trial (RCT) performed in 6 United Kingdom centers in the period between October 2009 and October 2011. Women were randomized to either SIMS-Ajust (C. R. Bard) performed under local anesthesia or TVT-O (Ethicon Inc.) performed under general anesthesia. Women completed validated symptom-severity and quality of life (QOL) questionnaires preoperatively and at 1 year. In addition, women completed the Patient Global Impression of Improvement (PGI-I) and underwent the Cough Stress Test (CST) at 1 year. The primary outcome at 12 months was the patient-reported success rate. Secondary outcomes included objective cure, reoperation rate, impact on women's urinary symptoms, QOL, and sexual function. Data was analyzed using SPSS-19 with significance level set at 5%. Results One hundred thirty-seven women were randomized into 2 groups: the SIMS-Ajust group (n = 69) and the TVT-O group (n = 68). At 1 year, there were no significant differences in the patient-reported success rate (odds ratio [OR] 0.895, 95% confidence interval [CI] 0.344-2.330, P = 1.000), objectives success rate (OR 0.929, 95% CI 0.382-2.258, P = 1.00), and reoperation rates (OR 0.591, 95% CI 0.136-2.576, P = .721) between the SIMS-Ajust and the TVT-O groups, respectively. A comparable number of women reported cure/improvement of urgency (P = .658), significant improvement in QOL (P = .190), and sexual function (P = .699) in both groups. Conclusion Adjustable-anchored SIMS (Ajust) is associated with comparable patient-reported and objective success rates when compared to standard midurethral sling (SMUS, TVT-O) at a minimum of 1-year follow-up. The results should be interpreted with caution due to the relatively small cohort size. Long-term follow-up of this RCT is required to ascertain the durability of these results. In the United Kingdom, the lifetime risk of women undergoing surgery for stress urinary incontinence (SUI) is 3.6%.1 The tension-free standard midurethral slings (SMUS), including retropubic tension-free vaginal tape (RP-TVT) and transobturator TVT (TO-TVT), have been the mainstay for surgical treatment of SUI in women over the last 2 decades. Single incision mini-sling procedures (SIMS) represent the third generation of midurethral slings (MUS). They were first introduced in 2004 with the concept of using a shorter tape through a single vaginal incision, anchored bilaterally to the obturator complex, and therefore provide a similar “midurethral hammock” to standard MUS while avoiding both the blind retropubic and the groin muscle trajectories. The postinsertion fixation process for SIMS fundamentally differs from tension-free SMUS in that they need a robust anchoring mechanism to the obturator complex, whereas SMUS depend on friction with nearby tissues in a relatively longer trajectory of insertion. The ultimate aim of SIMS is to provide a truly ambulatory and safe continence procedure, which is equally effective to SMUS. Unfortunately, the clinical effectiveness of the earlier types of SIMS have been disappointing with the main reasons cited for their failures as their lack of a robust anchoring mechanism to the obturator complex and their lack of postinsertion adjustability. The relatively new adjustable anchored SIMS, such as Ajust, Altis, and TFS, aim to overcome this deficiency in that they enable the surgeons to fully adjust the tension of the tape (ie, tighten or loosen) after ensuring a robust anchorage into the obturator complex. Limited evidence from small observational case series,2 and 3 has shown the “adjustable anchored SIMS” (Ajust, C. R. Bard, Inc., New Providence, NJ) to be associated with favorable patient and objective success rates. Although originally described under general anesthesia, we have recently shown the feasibility and acceptability of SIMS-Ajust to be performed under local anesthesia.