The effect of the Japanese Investigation Committee classification on hip joint survival after core decompression therapy in pre-collapsed avascular necrosis of the femoral head

Abstract

Aim: This study aimed to determine the failure rate of pre-collapse avascular necrosis (AVN) of the femoral head treated with core decompression (CD) and risk factors affecting the progression of the disease in patients by using an easily applicable staging system. . Material and Methods: A total of 174 hips from 134 patients diagnosed with precollapse AVN and treated with CD were retrospectively examined. Each hip was classified using the Japanese Investigation Committee (JIC) classification. The endpoint for joint survival following treatment was defined as the occurrence of total hip arthroplasty (THA). The risk analysis on joint survival of various independent variables (treatment type, age, gender, etiology) and the frequency of THA 2 and 5 years after treatment was calculated. Results: The mean age of the patients was 44.0 ± 15.0 years, with the majority being male (71.8%). THA was performed in 28.7% of treated hips within two years and 40.2% within five years. The frequency of THA application within two years was 2% for type A, 8% for type B, 40% for type C1 and 50% for type C2. Age (p=0.033), type C1 (p=0.028) and type C2 (p