Urethral sensation following reconstructive pelvic surgery

Introduction and hypothesis: Most urethral neuromuscular function data focus on efferent rather than afferent innervation. We aimed to determine if changes exist in urethral afferent nerve function before and after reconstructive pelvic surgery (RPS). Secondarily, we compared afferent urethral innervation in women with and without stress urinary incontinence undergoing RPS.

Methods: Participants underwent current perception threshold (CPT) and urethral anal reflex (UAR) testing prior to surgery and again post-operatively. Wilcoxon signed ranked test and Spearman’s correlations were used and all tests were two-sided. p = 0.05 was considered to indicate statistical significance.

Results: Urethral CPT thresholds increased significantly after RPS, consistent with decreased urethral afferent function. Pre-operative urethral CPT thresholds at 5 and 250 Hz were lower in SUI women (10 [IQR 5–29], 40 [32–750]) compared with continent women (63 [14–99], 73 [51–109]; p = 0.45, p = 0.020), signifying increased urethral sensation or easier activation of urethral afferents in SUI women.

Conclusions: Reconstructive pelvic surgery is associated with a short-term deleterious impact on urethral afferent function, as demonstrated by the higher levels of stimuli required to activate urethral afferent nerves (decreased urethral sensation) immediately after RPS. Women with SUI required lower levels of stimuli to activate urethral afferent nerves prior to RPS, although UAR latencies were similar regardless of concomitant SUI.