Inflamed joints will be analysed using region-of-interest (ROI) analysis on mDixon images, to determine the fat fraction (FF) in inflamed bone compared to normal bone. Polygonal ROIs will be hand-drawn across large joints in a standardized fashion. The pixel values derived from these ROIs will be analysed using multiple methods, including simple averaging and histographic analysis. Again, thresholding methods and analysis of skew/kurtosis will be explored as methods of assessing inflamed compared to normal joints.