Table 1 Modified Mankin score for evaluating the severity of cartilage damage.

Surface

0 = normal

1 = irregular

2 = fibrillated/vaculoated

3 = clefts/erosion

Cellularity

0 = normal

1 = slight decrease in chondrocytes

2 = marked decrease in chondrocytes

3 = no cells

Staining

0 = normal

1 = little decrease in staining

2 = marked decrease in staining

3 = no staining

Cloning

0 = normal

1 = occasional doublets

2 = doublets and triplets

3 = multiple nested cells