Radiographs and MRI were used to diagnose and define the stage of AVNFH. Fluoroscopy, plain computed tomography (CT) scanning, and MRI of both hips in frontal and frog positions were performed.
The mid-anterior portal is the best position to observe the anterosuperior femoral head which is the most common site of AVNFH. The femoral head was probed to assess the areas of necrosis under both fluoroscopy and arthroscopy.
Studies have shown that accurate staging is essential in choosing appropriate treatment for AVNFH.[sup],, The plain radiographs and MRI can diagnose and stage AVNFH,[sup], but they are suboptimal to detect early articular cartilage damage.
Therefore, in the treatment of AVNFH, besides the decompression of the femoral head, the secondary pathological changes in the hip cavity should also be treated.[sup] In our operations, hip arthroscopy was helpful to directly visualize the condition of joint, and we could clear the hypertrophy and synovial edema accurately.
Based on our results, we summarize the indications for hip arthroscopy in the treatment of early stage of AVNFH as: (1) failure of conservative treatment; (2) MRI showing significant synovial hyperplasia, effusion, and articular cartilage damage; (3) corpus liberum in articular cavity or labrum injury with mechanical symptoms.