Revision periacetabular osteotomy enhances joint function and activity level after failure of redirectional pelvic osteotomy at skeletal maturity.

Abstract

There is a paucity in the literature regarding functional outcomes of revision periacetabular osteotomy (R-PAO) after failure of previous redirectional pelvic osteotomy in a mature skeleton. This study aimed to compare the surgical and patient-reported outcome measures (PROM) between R-PAO and primary PAO. Patients undergoing R-PAO (n = 13) and primary PAO (n = 39) were matched in a 1:3 ratio for age, sex, and surgical date with a minimum follow-up of one year. PROM assessment included scores for pain, joint function (Modified Harris Hip Score -mHHS; International Hip outcome tool-12 -iHOT12), and activity level (University of California Los Angeles activity scale -UCLA). Postoperative outcomes were compared between the groups using independent-samples <i>t</i>-tests and Mann-Whitney U test. Multivariable linear regression was used to identify predictors of postoperative outcome improvement. Patients undergoing R-PAO had significantly worse preoperative joint function (mHHS 34.91 to 57.28, p < 0.001; iHot-12 33.17 to 46.22, p = 0.005) and activity level (UCLA 4.38 to 6.34, p = 0.004) compared to primary PAO. While achieving similar functional improvement (Δpre - post, p > 0.05) comparing both groups, postoperative mHHS (70.21 to 86.81, p = 0.002) and pain score (3.46 to 1.92, p = 0.010) remained significantly worse after R-PAO. Multivariable linear regression analysis revealed that preserved preoperative joint function (iHot-12 ß = 0.795, p < 0.001; mHHS ß = 0.696, p < 0.001) and activity level (UCLA ß = 0.360, p < 0.001), a lower BMI (iHot-12 ß = -2.011, p = 0.002; UCLA ß = -0.120, p = 0.041), and a sufficient postoperative anterior wall coverage (iHot-12 ß = 0.849, p < 0.001) are predictors of improved postoperative outcomes in both R-PAO and primary PAO. The failure of hip-preserving pelvic osteotomies in skeletally mature patients results in a substantial symptom burden and functional impairment. R-PAO represents a considerable treatment strategy that preserves the native hip joint and function, but postoperative outcomes after R-PAO remain inferior to those of primary PAO, due to the worse preoperative joint function.