Introduction and hypothesis: Our goal was to determine if there is a correlation between low back pain (LBP) and pelvic organ prolapse (POP) by assessing for change in LBP after surgical correction of prolapse.
Methods: Patients undergoing POP surgery were recruited to participate. They completed the Oswestry Disability Index (ODI), a validated back pain questionnaire, at their preoperative and postoperative visits at 1, 3, and 6 months. A higher ODI score (0-100) represents more severe disability. A 9-point change represents a minimal clinically important difference (MCID). The primary outcome was the change in ODI scores from preoperative to 3 months postoperative. We analyzed ODI scores with repeated measures analysis of variance (ANOVA). Power analysis showed that a sample size of 50 was needed for 88 % power to resolve a MCID on ODI.
Results: A total of 51 patients were recruited and 43 (84 %), 34 (67 %), and 36 (71 %) completed the 1-, 3-, and 6-month follow-up, respectively. The mean ODI scores at the preoperative and the 1-, 3-, and 6-month postoperative visits were 15, 19, 9, and 9. The mean ODI score from preoperative to 3 months postoperative improved by 5 points [confidence interval (CI) -9.2 to -0.5, p = 0.03]. Of the participants 7 (20.6 %, CI 11-35 %) experienced a MCID improvement, 24 (70.6 %, CI 56-83 %) reported no substantial change, and 3 (8.8 %, CI 3-20 %) experienced a MCID worsening.
Conclusions: Our study found a statistically significant but not clinically significant improvement of LBP after surgical repair of prolapse.