Fig. 6

Correlations between different quantitative parameters. Bivariate linear correlations were assessed using Spearman‘s correlation coefficient. a Inverse correlation between chondrocyte viability (%) and quantitative parameter (QP). Correlation coefficient (r = −0.654), corresponding P-value (p < 0.01); (b) Direct correlation between Mankin score and QP. Correlation coefficient (r = 0.673), corresponding P-value (p < 0.01); (c) Direct correlation between apoptotic chondrocytes (%) and QP. Correlation coefficient (r = 0.416), corresponding P-value (p < 0.01); (d) Direct correlation between Mankin score and apoptotic chondrocytes (%). Correlation coefficient (r = 0.493), corresponding P-value (p < 0.01); (e) Inverse correlation between red color intensity (%) and apoptotic chondrocytes (%). Correlation coefficient (r = −0.644), corresponding P-value (p < 0.01)