Fig. 2

Concordance and discordance between clinical joint swelling at PE and findings at MRI, for all 1759 MTP joints (a) and for non-swollen (b) and swollen MTP joints (c, d) separately. The number of joints per group are as follows: PE-MRI− n = 1325 joints, PE-MRI+ n = 281, PE+MRI− n = 79, and PE+MRI+ n = 74 joints. a Frequency of all 1759 MTP joints per category of PE/MRI. b 1606 non-swollen (PE−) MTP joints. c 153 swollen (PE+) MTP joints. d The same 153 PE+ joints as in c; in addition to the frequency of MRI inflammation, the frequency of intermetatarsal bursitis (IMB) is presented in swollen joints that had no MRI inflammation. MTP metatarsophalangeal joints, PE physical joint examination, PE− not swollen, PE+ swollen, MRI magnetic resonance imaging, MRI− absence of MRI-detected inflammation defined as synovitis, tenosynovitis, and osteitis, MRI+ presence of MRI-detected inflammation, IMB intermetatarsal bursitis, either present (+) or absent (−)