This document describes two staging systems for avascular necrosis (AVN): Steinberg staging and Ficat and Arlet staging. Steinberg staging classifies AVN into 6 stages based on radiographic findings such as cystic and sclerotic changes, subchondral lucency, and femoral head flattening. Ficat and Arlet staging also classifies AVN into 4 stages based on plain radiographs, MRI, bone scan, and clinical symptoms, ranging from normal findings to end-stage with secondary degenerative changes and femoral head flattening. Radiographic images are provided to illustrate some of the stages.

1. STAGES OF AVN
DR AVINASH DAHATRE
JR II RADIOLOGY

2. STEINBERG STAGING
 stage 0: normal or non-diagnostic radiographs, MRI and bone scan of at risk hip (often
contralateral hip involved, or 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 femoral head, with depression graded into
 mild: <2 mm
 moderate: 2-4 mm
 severe: >4 mm
 stage V: joint space narrowing with or without acetabular involvement
 stage VI: advanced degenerative changes

3. FICAT AND ARLET
STAGING OF AVN

4.  stage 0
 plain radiograph: normal
 MRI: normal
 clinical symptoms: nil
 stage I
 plain radiograph: normal or
minor osteopenia
 MRI: edema
 bone scan: increased uptake
 clinical symptoms: pain typically in the
groin

5.  stage II-
 plain radiograph: mixed osteopenia
and/or sclerosis and/or subchondral
cysts, without any subchondral
 MRI: geographic defect
 bone scan: increased uptake
 clinical symptoms: pain and stiffnes

6. COR T1WI

7. AXIAL T2WI SAG T2WI

8.  stage III:-
 plain radiograph: crescent sign
which is subchondral leucency
with sclerosis.
 MRI: same as plain radiograph
 clinical symptoms: pain and
stiffness +/- radiation to knee
and limp

9. SAG T1WI

10.  stage IV-
 plain radiograph: end-stage with
evidence of secondary
degenerative change.
 Flattening of femoral head
1. mild: <2 mm
2. moderate: 2-4 mm
3. severe: >4 mm
 MRI: same as plain radiograph
 clinical symptoms: pain and limp

11. COR T1WI

12. COR T2WI FATSAT