Predictors of Core Decompression Success in Patients with Femoral Head Avascular Necrosis

Avascular necrosis of the femoral head typically occurs in the young population. Core decompression in the precollapse stage provides pain relief and preservation of the femoral head. The results of core decompression vary considerably despite the early diagnosis. Clinicians concur that primary treatment should focus on preserving the natural surface of the joint. This study investigated the predictive risk factors of failure in femoral head decompression. We retrospectively reviewed 135 patients and 207 hips (77 male (127 hips) and 58 female (80 hips)) who underwent core decompression (mean age: 34.7 years [age range: 21-71]) from April 2010 to December 2017. All patients were followed by a mean of 57 months. All hips were in the precollapse stage (Ficat I, II).  A total of 207 hips were treated with core decompression surgery, and the overall success rate was 58%. The higher grade of Kerboul, Ficat, ARCO classifications, multifocal avascular necrosis of the femoral head, smoking, opium, and corticosteroids were significantly associated with a higher failure rate after core decompression in univariate analysis. In multivariate logistic regression analysis, the Kerboul and Ficat classifications, alcohol consumption, and multifocal avascular necrosis of the femoral head were significantly correlated with core decompression failure. The most common predictive factors in core decompression failure were Ficat II, Kerboul stage 3, multifocal avascular necrosis of the femoral head, and alcohol consumption.  In conclusion, we had an overall 58 % success rate in core decompression of femoral head avascular necrosis. Based on the results of this study, imaging evaluation and imaging-based classifications are the most valuable predictor factors for the success of core decompression. Consistent with previous reports, corticosteroid was not a significant predictor of core decompression failure.Level of evidence: III