Preoperative pelvic floor muscle diameter as a predictor of postoperative urinary incontinence in robotic-assisted laparoscopic total prostatectomy

Abstract

Objective

To assess the impact of preoperative pelvic floor muscle thickness on the early recovery of urinary continence following robot-assisted radical prostatectomy (RARP).

Patients and Methods

A retrospective study was conducted on 114 patients who underwent RARP at our institution between January 2019 and March 2021. Patients included were either confirmed to be pad-free or using only safety pads postoperatively or those with persistent incontinence, with a follow-up period of at least 6 months. Patient characteristics, perioperative outcomes, and pelvic floor muscle diameters were analysed. Preoperative magnetic resonance imaging or computed tomography was used to measure the diameters of the pelvic floor muscles, including the obturator internus and pubococcygeus muscles.

Results

The median patient age was 68 years (interquartile ranges [IQR]: 64–72 years), with a median Prostate-Specific Antigen (PSA) of 7.8 ng/ml (IQR: 5.4–10.6 ng/ml). The median prostate volume was 26.6 ml (IQR: 23–35 ml) in the early recovery group and 29 ml (IQR: 19.5–40 ml) in the delayed recovery group. The median time to continence recovery was 5.0 months (95% confidence interval: 4.2–5.7 months), with an incontinence resolution rate of 85.1%. Significant associations were found between the thicknesses of the obturator internus (p = 0.025) and pubococcygeal muscles (p = 0.004) and early continence recovery. Nerve-sparing procedures were also associated with faster recovery (p = 0.016). Multivariate analysis identified the thickness of both muscles as independent predictors of early continence recovery.

Conclusion

Preoperative evaluation of pelvic floor muscle thickness, particularly the obturator internus and pubococcygeal muscles, may help predict early postoperative urinary continence recovery in patients undergoing RARP. Preoperative pelvic floor muscle exercises to strengthen these muscles could improve the postoperative outcomes.