Table II.
Mean volumes and sphericities of the studied OARSI grade groups, together with the differences between means and P values from the linear mixed models
| OARSI grades 0–1 |
OARSI grades 3–3.5 |
Difference (95% CI) | P | ||
|---|---|---|---|---|---|
| Mean (SE)∗ | Mean (SE)∗ | ||||
| Volume (μm3) | |||||
| All well-segmented chondrons | Zone 1 | 5578 (681) | 8286 (794) | 2708 (613; 4803) | 0.012 |
| Zone 2 | 5909 (611) | 11,481 (563) | 5572 (4287; 6857) | <0.001 | |
| Zone 3 | 11,560 (650) | 19,686 (822) | 8126 (6625; 9626) | <0.001 | |
| Single cells | Zone 1 | 3465 (437) | 4024 (592) | 559 (1010; 2128) | 0.459 |
| Zone 2 | 4410 (484) | 6944 (490) | 2535 (1294; 3775) | <0.001 | |
| Zone 3 | 6354 (529) | 11,202 (654) | 4848 (3274; 6421) | <0.001 | |
| Clusters | Zone 1 | 6589 (841) | 9632 (926) | 3043 (514; 5571) | 0.020 |
| Zone 2 | 7244 (740) | 13,690 (661) | 6446 (4815; 8077) | <0.001 | |
| Zone 3 | 13,576 (746) | 21,346 (689) | 7770 (6043; 9497) | <0.001 | |
| Sphericity | |||||
| All well-segmented chondrons | Zone 1 | 0.78 (0.02) | 0.76 (0.02) | 0.02 (−0.05; 0.09) | 0.471 |
| Zone 2 | 0.80 (0.02) | 0.74 (0.01) | 0.06 (0.04; 0.09) | <0.001 | |
| Zone 3 | 0.74 (0.01) | 0.69 (0.01) | 0.05 (0.03; 0.06) | <0.001 | |
| Single cells | Zone 1 | 0.81 (0.04) | 0.80 (0.04) | 0.02 (−0.19; 0.22) | 0.775 |
| Zone 2 | 0.81 (0.01) | 0.78 (0.01) | 0.03 (0.00; 0.06) | 0.066 | |
| Zone 3 | 0.78 (0.01) | 0.73 (0.01) | 0.05 (0.02; 0.08) | 0.002 | |
| Clusters | Zone 1 | 0.76 (0.03) | 0.74 (0.02) | 0.02 (−0.05; 0.09) | 0.469 |
| Zone 2 | 0.78 (0.02) | 0.72 (0.02) | 0.06 (0.03; 0.08) | <0.001 | |
| Zone 3 | 0.72 (0.01) | 0.69 (0.01) | 0.03 (0.02; 0.05) | <0.001 | |
∗
Estimated means.