Table 2 Articular cartilage histologic evaluation criteria
Criteria for histologic evaluation of articular cartilage | |
|---|---|
Safranin O-fast green staining | |
0 | No loss |
1 | Mild loss |
2 | Moderate loss |
3 | Severe loss |
Chondrocyte loss | |
0 | No decrease in cells |
1 | Minimal decrease in cells |
2 | Moderate decrease in cells |
3 | Marked decrease in cells |
4 | Very extensive decrease in cells |
Structure | |
0 | Normal |
1 | Surface irregularities |
2 | One to three superficial clefts |
3 | More than three superficial clefts |
4 | One to three clefts extending into the middle zone |
5 | More than three clefts extending into the middle zone |
6 | One to three clefts extending into the deep zone |
7 | More than three clefts extending into the deep zone |
8 | Clefts extending to calcified cartilage |
Chondrocyte clones | |
0 | Normal |
1 | Minimal (≤4) |
2 | Moderate (> 4 but ≤8) |
3 | Marked (> 8) |
Tidemark integrity | |
0 | Intact |
1 | Crossed by blood vessels |
Tidemark duplication | |
0 | No change |
1 | Duplication of tidemark |
2 | No visible tidemark remaining |
Subchondral bone thickness | |
0 | Subchondral bone thickness less than thickness of cartilage |
1 | Subchondral bone thickness equal to thickness of cartilage |
2 | Subchondral bone thickness more than thickness of cartilage |