The Femoral Head Edema Zone A Novel Classification Scheme to Better Predict Osteonecrosis Progressio...

This study proposed a new classification, the Edema Zone classification, that uses Magnetic Resonance Imaging (MRI) images to grade the extent of edema in osteonecrosis of the femoral head (ONFH). The purpose of the study was 1) to examine how the Edema Zone classification compared to the Japanese Investigation Committee (JIC) classification s prognostic ability for early conversion to total hip arthroplasty (THA), and 2) to determine how accurately and reliably the Edema Zone classification performed as a classification system.