Association between spinopelvic parameters and postoperative urinary retention in thoracolumbar spine surgery: a propensity-matched analysis.

Postoperative urinary retention (POUR) is a frequent complication following spine surgery, with reported incidence rates ranging from 5 to 70%. While numerous risk factors have been identified, the relationship between spinopelvic parameters and POUR has not been previously investigated. This retrospective study examined the potential association between spinopelvic alignment and POUR in patients undergoing thoracolumbar spine surgery. We analyzed data from 420 patients who underwent surgery for degenerative thoracolumbar conditions between March 2021 and February 2024. After applying exclusion criteria and performing propensity score matching, 190 patients (95 with POUR, 95 without POUR) were included in the final analysis. Radiological parameters, including lumbar lordosis (LL), lower lumbar lordosis (LLL), pelvic tilt, sacral slope, and pelvic incidence, were assessed using preoperative and postoperative standing radiographs. Multivariable logistic regression analysis identified decreased preoperative LLL (< 27.77°) as an independent predictor of POUR (OR = 2.08, 95% CI = 1.10-3.91, p = 0.024). Additionally, higher intraoperative mean arterial pressure (> 75.35 mmHg) was associated with increased POUR risk (OR = 2.73, 95% CI = 1.08-6.88, p = 0.033). Our findings suggest that spinopelvic alignment, particularly decreased LLL, may play a previously unrecognized role in the development of POUR following thoracolumbar spine surgery. This novel association expands our understanding of POUR pathophysiology and could inform preoperative risk assessment and perioperative management strategies. Future prospective studies are warranted to validate these findings and explore the underlying mechanisms.