Clinical significance of relative pelvic version measurement as a predictor of low back pain after total hip arthroplasty

Purpose To evaluate the association between the preoperative global alignment and proportion (GAP) score and low back pain (LBP) after total hip arthroplasty (THA). Methods This was a retrospective case–control study of 200 patients who underwent primary unilateral THA for hip osteoarthritis. The following variables were compared between individuals with (n = 76) and without (n = 124) LBP after THA over a mean follow-up of 2 years: age, sex, GAP score, and patient-reported outcome measures. Logistic regression and receiver operating characteristic curve analyses were used to detect predictive factors. Results The following parameters were predictive of post-THA LBP: relative pelvic version (RPV)