RISK FACTORS FOR ACETABULAR EROSION AFTER BIPOLAR HEMIARTHROPLASTY: A RETROSPECTIVE COHORT STUDY
Abstract
Introduction: Acetabular erosion is a significant, late-stage complication in patients undergoing hemiarthroplasty. This study aimed to investigate the risk factors for acetabular erosion in patients undergoing bipolar hemiarthroplasty for proximal femoral fractures. Methods: This single-center retrospective study was performed on 126 patients aged between 55-85 years who underwent bipolar hemiarthroplasty for proximal femoral fractures between January 2017 and November 2023 and had at least 2 years of radiological follow-up. The demographic data, femoral stem type, and bipolar femoral head diameter of patients were recorded. Femoral offset (FO) and leg length discrepancy (LLD) were measured from early postoperative anteroposterior pelvic radiographs. Acetabular erosion was graded based on the Baker classification on final follow-up radiographs. Statistical analyses were performed using the t test, Mann–Whitney U test, chi-square test, and Spearman correlation analysis. Results: The mean age of patients was 78.10 ± 7.66 years. 74.6% were female, and the mean follow-up period was 38.67 ± 12.45 months. According to the Baker classification, 29.4% of patients had grade 0, 42.9% had grade 1, 18.3% had grade 2, and 9.5% had grade 3 erosion. Acetabular erosion was found to be significantly more common in female patients (p = 0.025). An increased risk of acetabular erosion was observed in patients with a femoral head diameter ≤48 mm (p = 0.043; odds ratio = 3.10; 95% confidence interval = 1.00–9.66). A significant correlation was noted between increased follow-up duration and increased degree of acetabular erosion (p = 0.001). No significant correlation was found between age, femoral stem type, LLD, FO discrepancy, osteoporosis grades (T-score), and acetabular erosion. Conclusion: Female sex and a bipolar femoral head diameter ≤48 mm were the main risk factors for the development of acetabular erosion after hemiarthroplasty and should be considered in surgical decision-making.