Management of Urosymphyseal Fistula and Pelvic Osteomyelitis: A Comprehensive Institutional Experience and Improvements in Pain Control.

Background: Urosymphyseal fistula (USF) is an uncommon but painful and devastating condition typically occurring after radiotherapy for pelvic malignancy, with a delayed diagnosis and a risk of opioid dependence.

Objective: To characterize our institutional experience and determine the impact of intervention for USF on pain control and opioid use.

Design, Setting, And Participants: We evaluated data for 33 adult patients diagnosed with USF and managed at a quaternary institution between 2009 and 2021.

Outcome Measurements And Statistical Analysis: We assessed chronic opioid use, pain scores, prior therapy for pelvic malignancy, prior endoscopic procedures, microbiology and histology congruence, and postoperative complications. For comparative analyses we used a χ test or Fisher's exact test for categorical variables and a Wilcoxon signed-rank test for continuous variables.

Results And Limitations: Nearly 94% of the patients had received prior pelvic radiotherapy and >80% occurred in 2016-2021 but were not diagnosed until a median of 10 mo (interquartile range [IQR] 3.5-19.5) following endoscopic procedure(s). Osteomyelitis was suspected in 78.8% of imaging reports and nearly 70% had a positive preoperative urine culture. Over 90% of patients underwent cystectomy, pubic bone debridement or resection, and a soft-tissue pedicle flap. Preoperative urine cultures were concordant with 60% of intraoperative tissue/bone cultures. Histologic osteomyelitis was identified in 85% and concordant with 80% of preoperative imaging. Clavien-Dindo grade ≥3 complications occurred in 15.6%. The median pain score decreased from 4 (IQR 0-8) preoperatively to 0 (IQR 0) postoperatively (p < 0.001). Chronic opioid use decreased from 39.4% to 21.2% (p = 0.02).

Conclusions: Pelvic osteomyelitis may complicate USF and commonly manifests with severe, persistent pain. USF incidence may be increasing or at least increasingly recognized, but diagnosis is delayed. Definitive management results in significant improvements in pain perception and a decrease in chronic opioid use.

Patient Summary: We examined features of urinary fistulas, which are abnormal openings or connections between part of the urinary tract and another structure. Patients with a urinary fistula involving the pelvic bones can present with severe pain, but diagnosis of the condition is often delayed. Removal of some pelvic bone with bladder removal or repair can result in a decrease in long-term pain and in the use of opioid drugs for pain relief.