Table 2 Mankin score for evaluation of articular cartilage degeneration
| Grade | ||
|---|---|---|
| I | Structure | |
| a. Normal | 0 | |
| b. Surface irregularity | 1 | |
| c. Pannus and surface irregularity | 2 | |
| d. Clefts to transitional zone | 3 | |
| e. Clefts to radial zone | 4 | |
| f. Clefts to calcified zone | 5 | |
| g. Complete disorganization | 6 | |
| II | Cells | |
| a. Normal | 0 | |
| b. Diffuse hypercellularity | 1 | |
| c. Cloning | 2 | |
| d. Hypocellularity | 3 | |
| III | Safranin–Orange staining | |
| a. Normal | 0 | |
| b. Slight reduction | 1 | |
| c. Moderate reduction | 2 | |
| d. Severe reduction | 3 | |
| e. No dye note | 4 | |
| IV | Tidemark integrity | |
| a. Intact | 0 | |
| b. Crossed by blood vessels | 1 |