Patients with RA often develop multi-level symmetrical and correlated joint damages in both hands and feet. In fact, through analyzing total joint damage scores at the image level, we observed medium to high Pearson’s correlations at three aspects: (1) between joint space narrowing and bone erosion, (2) between the left side and right side, and (3) between hands and feet (Table 1). We also calculated the cross-patient pairwise correlations among all joints and found ubiquitous correlations shown as heatmaps in Fig. 7.