Abstract
Objective
1. To test, through tri-dimensional analysis, whether cartilage thickness at the posterior aspect of the medial and lateral condyles differs in medial femorotibial OA knees compared to matched non-OA knees.
2. To determine the locations of thickest cartilage at posterior aspects of femoral condyles.
Design
Two groups of non-OA (n=40) and severe medial femorotibial OA (n=40) patients of over 50 years of age, matched for gender, age and bone morphometric parameters, with radiographs and CT arthrograms of the knee, were randomly selected retrospectively. CT arthrograms were segmented to measure the mean cartilage thickness, the maximal cartilage thickness and the location of maximal cartilage thickness in a region of interest at the posterior aspect of the condyles.
Results
For the medial condyle, mean and maximum cartilage thicknesses were statistically significantly higher in OA knees compared to non-OA knees (1.66 vs. 1.46mm, p=0.012 and 2.53 vs. 2.13mm, p=0.0006 respectively). The thickest cartilage was located in the half most medial aspect of the medial condyle for both groups. For the lateral condyle, no statistically significant difference between non-OA and OA knees was found (p≥0.16).
Conclusions
Cartilage at the posterior aspect of the medial condyle, but not the lateral condyle is statistically significantly thicker in OA knees compared to matched non-OA knees. The thickest cartilage was located in the half most medial aspect of the posterior medial condyle. These results will serve as the basis for future research to determine whether the thicker cartilage corresponds to cartilage hypertrophy due to reparative processes in reaction to OA.