Table 2 Classification and prognostic assessment system of avascular necrosis
Types | The evaluation index |
|---|---|
Ratliff’s classification of avascular necrosis (AVN) | |
Type I | Diffuse density increases in the femoral head accompanied by complete collapse of the epiphysis |
Type II | Partial head involvement with slight accompanying epiphyseal collapse and osteonecrosis |
Type III | Areas of avascular necrosis, with the range of necrosis usually limited to between the epiphyseal and fracture lines |
Ratliff system of clinical and radiographic assessment | |
Good | Clinical: no pain, normal or slightly limited hip movement, normal daily activity |
Radiographic: normal or mild deformity of the femoral neck | |
Fair | Clinical: occasional pain, limited hip movement less than 50%, normal daily activity |
Radiographic: severe deformation of the femoral neck and mild femoral head necrosis | |
Poor | Clinical: persistent pain, limited hip movement by more than 50%, and limited daily activity |
Radiographic: severe femoral head necrosis, degenerative arthritis, arthrodesis | |