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

P Omoumi; H Babel; B M Jolles; J Favre

doi:10.1016/j.joca.2018.12.014

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

Osteoarthritis Cartilage. 2019 Apr;27(4):621-629. doi: 10.1016/j.joca.2018.12.014. Epub 2019 Jan 3.

Authors

P Omoumi¹, H Babel², B M Jolles³, J Favre²

Affiliations

¹ Department of Diagnostic and Interventional Radiology, Centre Hospitalier Universitaire and University of Lausanne, Lausanne, Switzerland; Department of Radiology, Cliniques Universitaires St Luc - UC Louvain, Brussels, Belgium; Swiss BioMotion Lab, Department of Musculoskeletal Medicine, Centre Hospitalier Universitaire Vaudois and University of Lausanne, Lausanne, Switzerland. Electronic address: patrick.omoumi@chuv.ch.
² Swiss BioMotion Lab, Department of Musculoskeletal Medicine, Centre Hospitalier Universitaire Vaudois and University of Lausanne, Lausanne, Switzerland.
³ Swiss BioMotion Lab, Department of Musculoskeletal Medicine, Centre Hospitalier Universitaire Vaudois and University of Lausanne, Lausanne, Switzerland; Institute of Micro Engineering, Ecole Polytechnique Fédérale de Lausanne, Lausanne, Switzerland.

PMID: 30611905
DOI: 10.1016/j.joca.2018.12.014

Abstract

Objective: 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.

Methods: 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.

Results: 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 < 0.001). Additional positive/negative relationships in the non-OA/OA knees were observed between sBMD and CTh measures in the medial compartment.

Conclusions: The positive correlation between sBMD and CTh in non-OA knees, and the negative one in OA knees, bring support to the theory of a subchondral bone/cartilage functional unit, which could help to better understand the pathophysiology of OA.

Keywords: Bone mineral; CT arthrography; Cartilage thickness; Density; Osteoarthritis; Subchondral bone.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Algorithms*
Arthrography / methods*
Bone Density
Cartilage, Articular / diagnostic imaging*
Child
Cross-Sectional Studies
Female
Follow-Up Studies
Humans
Imaging, Three-Dimensional / methods*
Male
Osteoarthritis, Knee / diagnosis*
Retrospective Studies
Tomography, X-Ray Computed / methods*