"It is based on the radiographic appearance and location of lesion. It primarily differs from the other systems by quantifying the involvement of the femoral head which allows direct comparison between series1. Seven stages of involvement are identified. Following staging, the extent of involvement of the femoral head is recorded as mild, moderate or severe."
"Classification "
"stage 0: normal or non-diagnostic radiographs, MRI and bone scan of at-risk hip (often contralateral hip involved, or the patient has risk factors and hip pain)"
"stage I: normal radiograph, abnormal bone scan and/or MRI"
"stage II: cystic and sclerotic radiographic changes"
"stage III: subchondral lucency or crescent sign"
"stage IV: flattening of the femoral head, with depression graded into:"
"stage V: joint space narrowing with or without acetabular involvement"
"stage VI: advanced degenerative changes"
"A: mild:"
"C: severe: >30%"
"A: mild: subchondral collapse (crescent) beneath"
"B: moderate: crescent beneath 15-30%"
"C: severe: crescent beneath >30%"
"A: mild:"
"B: moderate: 15-30% collapsed or 2-4 mm depression"
"C: severe: >30% collapsed or >4 mm depression"
"A, B, or C: average of femoral head involvement, as determined in stage IV, and estimated acetabular involvement"
"It is based on the radiographic appearance and location of lesion. It primarily differs from the other systems by quantifying the involvement of the femoral head which allows direct comparison between series1. Seven stages of involvement are identified. Following staging, the extent of involvement of the femoral head is recorded as mild, moderate or severe."
"A: mild:"
"B: moderate: 15-30%"
"A: mild: subchondral collapse (crescent) beneath"
"B: moderate: crescent beneath 15-30%"
"A: mild:"
"B: moderate: 15-30% collapsed or 2-4 mm depression"
Expected headings
"Classification "
"It is based on the radiographic appearance and location of lesion. It primarily differs from the other systems by quantifying the involvement of the femoral head which allows direct comparison between series1. Seven stages of involvement are identified. Following staging, the extent of involvement of the femoral head is recorded as mild, moderate or severe."
"stage 0: normal or non-diagnostic radiographs, MRI and bone scan of at-risk hip (often contralateral hip involved, or the patient has risk factors and hip pain)"