A Study of FolateScan in Patients With Knee Osteoarthritis

The purpose of this study is to evaluate 99mTc - EC20 imaging (FolateScan), a Nuclear Medicine imaging technology that enables localization of activated macrophages in the joints of participants with knee osteoarthritis (OA). Twenty five participants with symptomatic unilateral or bilateral knee OA will undergo a one-time evaluation of the knee as follows: knee radiography, FolateScan of the knees and whole body, musculoskeletal exam, questionnaires, sampling of blood, urine and synovial fluid for analysis of inflammatory markers. Data analysis will be cross-sectional and include a comparison of the location and intensity of EC20 uptake with the following: radiographic knee OA severity, clinical measures of disease severity, cytokine expression, and synovial fluid cell count.