Associations of Popliteal Artery Wall Morphology at MRI and Knee Osteoarthritis in the Osteoarthritis Initiative.

Abstract

Background Vascular factors have been associated with osteoarthritis (OA), but the association between popliteal artery wall morphology and symptomatic and radiographic knee OA outcomes over time remains unclear. Purpose To evaluate the associations between MRI-derived measures of popliteal artery wall morphology (localized wall thickening and global wall burden) and symptomatic and radiographic knee OA outcomes. Materials and Methods In this secondary analysis of the Osteoarthritis Initiative (February 2004 to October 2015), baseline knee MRI scans were analyzed to quantify maximum wall thickness and normalized wall index (NWI). Symptomatic OA was assessed using Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) pain scores, and radiographic OA using Kellgren-Lawrence (KL) grade. Cross-sectional and longitudinal associations were assessed using linear regression and Cox proportional hazards models, respectively, adjusted for demographic and clinical covariates. Results A total of 9333 knees from 4710 participants (mean age, 61.1 years ± 9.2 [SD]; 2753 female) were included. Each 1-mm increase in maximum wall thickness was associated with higher WOMAC pain scores (β = 2.0; P < .001) and KL grades (β = 0.1; P < .001), as well as symptomatic worsening (hazard ratio = 1.10 [95% CI: 1.02, 1.19]; P = .02) and incident radiographic OA (hazard ratio = 1.21 [95% CI: 1.02, 1.44]; P = .044). Each 10% increase in NWI was associated with higher WOMAC pain scores (β = 6.7; P < .001) and symptomatic worsening (hazard ratio = 1.38 [95% CI: 1.20, 1.58]; P < .001) but was inversely associated with KL grade (β = -0.1; P = .001) and incident radiographic OA (hazard ratio = 0.60 [95% CI: 0.43, 0.83]; P = .004). Conclusion Localized popliteal arterial wall thickening was associated with symptomatic OA worsening and incident radiographic OA, whereas diffuse wall remodeling was associated with symptomatic OA worsening and was inversely associated with radiographic outcomes. Clinical trial registration no. NCT00080171 © RSNA, 2026 Supplemental material is available for this article. See also the editorial by Jarraya and Harandi in this issue.