Association Between Popliteal Artery Wall Thickness and Knee Structure in Adults Without Clinical Disease of the Knee

Objective. There is evidence of a vascular contribution to the pathogenesis of osteoarthritis (OA). The aim of this study was to examine the association between popliteal artery wall thickness, which was previously shown to be associated with the risk of OA, and structural changes in the knee in an asymptomatic cohort. Methods. A total of 297 adults with no significant knee pain, injury, or history of clinical knee disease were recruited. Participants underwent magnetic resonance imaging of the knee at baseline and 2 years later. Popliteal artery wall thickness, knee cartilage volume, and bone marrow lesions (BMLs) were assessed. Results. Of 278 participants with valid popliteal artery wall thickness measurements, 254 (91.4%) completed the 2-year followup assessment. After adjusting for age, sex, body mass index, and tibial bone area, increased popliteal artery wall thickness was found to be associated with a reduced medial tibial cartilage volume (B = -6.7 [95% confidence interval (95% CI) -12.9, -0.6], P = 0.03) and an increased rate of medial tibial cartilage volume loss (B = 0.06 [95% CI 0.01, 0.12], P = 0.03). There was a trend toward worsening of medial tibiofemoral BMLs in relation to increased popliteal artery wall thickness (odds ratio 1.07 [95% CI 0.99, 1.15]; P = 0.07). No significant associations with the lateral tibiofemoral compartment were observed. Conclusion. Increased popliteal artery wall thickness was associated with adverse changes in knee structure, as evidenced by reduced medial tibial cartilage volume, increased rate of cartilage volume loss, and a trend toward worsening of BMLs over 2 years. These findings suggest an association between vascular pathology and early structural changes in the knee, which supports the hypothesis that vascular health may play a role in the development of knee OA.