Medial Femoral Offset and Early Pelvic Obliquity Correction After Unilateral Total Hip Arthroplasty

Background: Pelvic obliquity (PO) may alter perceived acetabular orientation and increase the risk of component malpositioning after total hip arthroplasty (THA). Femoral offset reconstruction influences pelvic mechanics during gait; however, the effect of intraoperative offset adjustment on postoperative PO remains unclear. Methods: This cross-sectional study analyzed data from a prospective arthroplasty registry including adult patients who underwent unilateral cementless THA between 2018 and 2023 and had preoperative PO. Forty-six patients (mean age 66.8 ± 8.2 years) were included. Medial offset (MO), vertical offset, PO angle, and spinopelvic parameters were measured on standardized radiographs obtained preoperatively and at 6 months postoperatively. Patients were categorized based on postoperative improvement in PO. Functional outcomes were assessed using the Harris Hip Score and Western Ontario and McMaster Universities Osteoarthritis Index. Statistical analyses included correlation testing, chi-square analysis, and logistic regression. Results: < .001). Conclusions: Medial offset adjustment based on the direction of preoperative PO contributes to restoration of coronal pelvic balance and improved function after THA.