Imaging comparison for avascular necrosis of the femoral head induced by different etiologies / 中国组织工程研究

ABSTRACT

bone fracture, mild col apse of the articular surface;femoral head deformation, bone fracture, articular surface col apse, hip degeneration. MRI of four categories of avascular necroses appeared as phase Ⅰline-like low signal of weight-bearing area of femoral head on T1WI, high signal on T2WI as the main change. Phase Ⅱclear boundary crescent-shaped uneven signal on T1WI, T2WI displayed moderately higher, uneven slightly lower signal around, showing a typical two-line sign. Phase Ⅲfemoral head deformation, subchondral fracture, col apse, crescent formation, zonal low signal on T1WI, medium or high signal on T2WI. Phase Ⅳ, Ⅴcomplete destruction of articular cartilage, joint space narrowing, significant col apse and deformation of the femoral head, non-specific secondary osteoarthritis of the acetabulum, such as sclerosis, cystic degeneration and marginal osteophyte. The X-ray, CT, MRI performances of four types of avascular necroses at the same period were basical y the same.