Etiologies and outcome of osteonecrosis of the femoral head: Etiology and outcome study in a Taiwan population.

BACKGROUND Osteonecrosis of the femoral head (ONFH) is an important indication for total hip arthroplasty in Taiwan. We demonstrated the etiologies of ONFH and outcomes based on stratification of patients according to different etiologies. METHODS We reviewed medical records and images from January 2000 to May 2010 in our database with the diagnosis of "osteonecrosis of the femoral head." We categorized all patients into different etiologies, including corticosteroid, alcohol, and idiopathic. All patients received subsequent follow up for ipsilateral precollapse ONFH and contralateral disease-free femoral head status after initial diagnosis. RESULTS Of the 1153 patients who had undergone 1674 hip surgeries including core decompression and total hip replacement, alcohol use was the most prevalent etiology in our population (45.2%). Patients with corticosteroid- and alcohol-associated ONFH were younger and more likely to have bilateral disease. Patients with alcohol- or steroid-associated ONFH were found to have a higher rate of contralateral disease and faster progression of precollapse ONFH than patients who had or had not undergone core decompression. CONCLUSION Alcohol use had the greatest impact on ONFH in our population. Nonidiopathic ONFH patients had the worst outcome. Understanding the nature of progression of ONFH and incidence of contralateral disease may provide great prognostic value to detect and perform early intervention.