Treatment of adolescents with a periacetabular osteotomy after previous pelvic surgery hip

Background: Although the success of the Bernese periacetabular osteotomy (PAO) has been reported for primary dysplasia, there is no study analyzing the radiographic, functional, and gait results of the PAO to correct residual hip dysplasia after previous pelvic surgery. Questions/purposes: We assessed (1) radiographic and (2) functional and gait outcomes of patients treated with a PAO after previous pelvic surgery (PPSx) and compared their results with results of patients with no previous surgery (NPSx) to determine whether the PAO was equally effective in patients with revision pelvic surgery. Methods: Twenty-nine dysplastic hips in 26 patients (average age, 16.3 years) were included: 13 in the PPSx group and 13 in the NPSx group. Radiographic parameters included the lateral center-edge angle, acetabular index, and femoral head extrusion index measured preoperatively and at 6 months and 1 year. We assessed preoperative and postoperative function using the Harris hip score (HHS). Preoperative and postoperative gait analysis included the hip abductor impulse. Results: Improvements in groups were seen from preoperatively to 1 year postoperatively for the lateral center-edge angle, acetabular index, and femoral head extrusion index without differences between groups. The modified HHSs improved at 6 months and were maintained at 1 year for patients in both groups without differences between groups. The hip abductor impulse returned to preoperative values at 6 months in the NPSx group but not until 1 year in the PPSx group. Conclusions: The Bernese PAO is effective in providing similar final radiographic and functional results, however, a trend toward decreased hip flexion and abduction power at 1 year was seen with previous pelvic surgery. Level of Evidence: Level II, therapeutic study. See Guidelines for Authors for a complete description of levels of evidence.