Relationships between cartilage thickness and subchondral bone mineral density in non-osteoarthritic and severely osteoarthritic knees: In vivo concomitant 3D analysis using CT arthrography

• Published in: Osteoarthritis and cartilage 2019-04, Vol.27 (4), p.621-629
• Main Authors: Omoumi, P., Babel, H., Jolles, B.M., Favre, J.
• Format: Article
• Language: English
• Subjects: Bone mineral; Cartilage thickness; CT arthrography; Density; Osteoarthritis; Subchondral bone
• ISSN: 1063-4584; 1522-9653
• DOI: 10.1016/j.joca.2018.12.014

To test whether subchondral bone mineral density (sBMD) and cartilage thickness (CTh) of femoral condyles are correlated in knees without and with severe medial femorotibial osteoarthritis (OA), using a subregional analysis with computerized tomography (CT) arthrography. CT arthrograms of 50 non-OA (18 males, 58.7 (interquartile range (IQR) = 6.6 years)) and 50 severe medial OA (24 males, 60.5 (IQR = 10.7) years) knees, were retrospectively analyzed. Bone and cartilage were segmented using custom-designed software, leading to 3D models on which each point of the subchondral surface is given a CTh and sBMD value. The average sBMD and CTh were then calculated for the entire weight-bearing regions as well as specific subregions of interest. Linear bivariate and multivariable analyses were performed to test for relationships between sBMD and CTh (regional and subregional measures, or medial-to-lateral ratios), with confounders of age, gender, femoral bone size and femorotibial angle. In non-OA knees, the sBMD and CTh medial-to-lateral ratios were positively correlated for the total region and the external and internal subregions (r ≥ 0.341, P ≤ 0.015). In OA knees, sBMD and CTh medial-to-lateral ratios were negatively correlated for the total region and the external and central subregions (r ≤ −0.538, P