Fellow Physician Boston University University of Washington Boston, MA, United States
Jean Liew1, Ali Guermazi2, Mohamed Jarraya3, Na Wang1, David Felson2, Cora E. Lewis4, Michael Nevitt5, James Torner6, John A. Lynch7 and Tuhina Neogi1, 1Boston University School of Medicine, Boston, MA, 2Boston University, Boston, MA, 3Massachusetts General Hospital, Boston, MA, 4University of Alabama at Birmingham, Birmingham, AL, 5University of California at San Francisco, Orinda, CA, 6University of Iowa, Iowa City, IA, 7UCSF, San Francisco, CA
Background/Purpose: Intra-articular (IA) mineralization due to calcium crystal deposition may contribute to OA pathology through inflammation, release of pro-catabolic factors, or altered cartilage biomechanical properties. Prior studies have been conflicting regarding whether radiographic chondrocalcinosis is associated with OA symptoms or structural progression. Studies to date have generally assessed effects of chondrocalcinosis on the knee as a whole rather than considering potential localized effects, thus potentially contributing to conflicting understanding of this association. Thus, whether IA mineralization is a cause or consequence of OA remains unclear. We studied the relation of radiographic chondrocalcinosis with OA structural outcomes in older adults, with a focus on localized effects of chondrocalcinosis upon compartmental cartilage lesions on MRI.
Methods: Participants from the Multicenter Osteoarthritis (MOST) study, a longitudinal prospective cohort of older adults, who had knee radiographs and MRIs, were included in this cross-sectional analysis. Chondrocalcinosis was assessed on the PA and lateral view of knee radiographs. Chondrocalcinosis was scored as present on either view, and also categorized as being present in the medial or lateral tibiofemoral (TF) compartments on the PA view. The presence of cartilage lesions on MRI was defined as a score of ≥2 on the semi-quantitative WORMS. We evaluated the relation of radiographic chondrocalcinosis to the presence of any cartilage lesions on MRI in the whole knee using binomial regression. We additionally performed a location-specific analysis in which we assessed the relation of chondrocalcinosis in a particular compartment (i.e., the medial or lateral TF joint) to cartilage damage in the same compartment on MRI, using generalized estimating equations to account for correlations between compartments within a knee. Analyses were adjusted for age, sex, race, site, and body mass index (BMI).
Results: We included 2539 participants (mean age 62.8±10.3 years, 56.7% female, mean BMI 29.1±5.4 kg/m2). Overall, 7% had chondrocalcinosis anywhere in the knee and cartilage damage was present in 72.8%. Chondrocalcinosis was not associated with presence of cartilage lesions in the knee overall (prevalence ratio [PR] 1.02, 95% CI 0.93-1.11). However, presence of chondrocalcinosis in a particular TF compartment was associated with higher prevalence of cartilage lesions in the same compartment (PR 1.25, 95% CI 1.05-1.49).
Conclusion: Radiographic chondrocalcinosis was cross-sectionally associated with higher prevalence of cartilage lesions on MRI in the same compartment. These findings support a role of IA mineralization (visualized on radiographs as chondrocalcinosis) in the pathogenesis of knee OA, and localized effects of calcium crystal deposition on cartilage damage.
Disclosures: J. Liew, None; A. Guermazi, AstraZeneca, Merck/MSD, Pfizer, Novartis; M. Jarraya, None; N. Wang, None; D. Felson, None; C. Lewis, None; M. Nevitt, None; J. Torner, None; J. Lynch, None; T. Neogi, Novartis, Pfizer/Lilly, Regeneron.
