Avascular Necrosis and Subchondral Collapse of the Femoral Head After Intra-Articular Corticosteroid Injection: A Case Report

A 51-year-old female with no history of chronic alcohol or steroid use presented with right hip pain. X-ray and magnetic resonance imaging (MRI) showed osteoarthritic changes without evidence of avascular necrosis (AVN) or subchondral collapse of the femoral head, and the patient elected to receive an intra-articular corticosteroid injection to address the pain. She returned four months post-injection, reporting the pain had returned after 2-3 months of relief and was more severe than pre-injection. She opted for a second corticosteroid injection, but the procedure was stopped when heme was aspirated from the joint. A repeat MRI showed secondary femoral head AVN and subchondral collapse. Conservative management failed, resulting in a total hip arthroplasty (THA). This case highlights the importance of follow-up to detect warning signs of femoral head AVN after corticosteroid injection, such as rebound pain. Early diagnosis of AVN may prevent the progression and need for THA.