OBJECTIVE: To investigate the two-year association of varus knee thrust observed during walking to the odds of worsening WOMAC knee pain in older adults with or at risk of OA. METHODS: Video recordings of self-paced walking trials of Multicenter Osteoarthritis Study (MOST) participants were assessed for the presence of varus thrust at baseline. Knee pain was assessed using the WOMAC questionnaire at baseline and at two years. Logistic regression was used to estimate the odds of worsening (defined as either any increase in WOMAC score or clinically-important worsening) knee pain, adjusting for age, sex, race, BMI, clinic site, gait speed, and static knee aligment. Analyses were repeated stratified by baseline radiographic OA status and among the subset of knees without baseline WOMAC pain. RESULTS: 1623 participants contributed 3204 knees. Varus thrust was observed in 31.5% of knees. Knees with varus thrust had 1.44 times (95% CI: 1.19, 1.73) the odds of any and 1.37 times (95% CI: 1.11, 1.69) the odds of clinically-important worsening WOMAC pain compared to knees without thrust. Knees with thrust without baseline WOMAC pain had 2.01 (95% CI: 1.47, 2.74) times the odds of incident total pain. CONCLUSION: Results indicate that varus thrust is a risk factor for worsening and incident knee pain. Targeting varus thrust through non-invasive therapies could prevent development or worsening of knee pain in older adults with or at risk for knee OA. This article is protected by copyright. All rights reserved.