title: Magnetic resonance imaging of wrist and finger joints in healthy subjects occasionally shows changes resembling erosions and synovitis as seen in rheumatoid arthritis.
abstract: OBJECTIVE
  To explore the presence of changes resembling rheumatoid arthritis erosions and synovitis in metacarpophalangeal (MCP) and wrist joints of healthy individuals on magnetic resonance imaging (MRI) and to compare the MRI findings with conventional radiographic, clinical, and biochemical findings.
  
  
  METHODS
  Twenty-eight healthy individuals were studied. Contrast-enhanced MRI and conventional radiography of the dominant wrist and second through fifth MCP joints were performed, coupled with standard clinical assessments and biochemical analyses. MR images were evaluated according to the latest OMERACT (Outcome Measures in Rheumatology Clinical Trials) recommendations with respect to synovitis, erosions, and bone marrow edema.
  
  
  RESULTS
  Conventional radiography revealed erosion-like changes in 1 of 224 MCP joint bones (0.4%) and in 1 of 420 wrist joint bones (0.2%). MRI depicted low-grade erosion-like changes in 5 of 224 MCP joint bones (2.2%) and in 7 of 420 wrist joint bones (1.7%), but postcontrast enhancement within the lesion was detected in only 8.3% of these. MRI depicted low-grade synovitis-like changes in 10 of 112 MCP joints (8.9%) and in 8 of 84 assessed wrist areas (9.5%), while only minimal early synovial enhancement was detected by dynamic MRI. Three subjects had elevated serum levels of C-reactive protein, and these subjects displayed 44.5% of the synovitis-like changes and 41.7% of the erosion-like changes. Bone marrow edema-like changes were not found in any joints.
  
  
  CONCLUSIONS
  Changes resembling mild synovitis or small bone erosions are occasionally found in the MCP and wrist joints of healthy controls. Signs of synovitis on dynamic MRI, enhancement within bone erosion-like changes, and signs of bone marrow edema appear rarely or are absent in healthy controls. These signs may thus prove to be very specific in the distinction between arthritic and normal joints.
authors.affiliation: Department of Radiology, Copenhagen University Hospital at Hvidovre, Hvidovre, Denmark. ejbjerg@dadlnet.dk
authors.forename: Bo
authors.initials: B
authors.lastname: Ejbjerg
authors.forename: Eva
authors.initials: E
authors.lastname: Narvestad
authors.forename: Egill
authors.initials: E
authors.lastname: Rostrup
authors.forename: Marcin
authors.initials: M
authors.lastname: Szkudlarek
authors.forename: Søren
authors.initials: S
authors.lastname: Jacobsen
authors.forename: Henrik S
authors.initials: HS
authors.lastname: Thomsen
authors.forename: Mikkel
authors.initials: M
authors.lastname: Østergaard
mesh_terms: D000328:Adult; D000368:Aged; D001172:Arthritis, Rheumatoid / Q000000981:diagnostic imaging / Q000473:pathology*; D001853:Bone Marrow / Q000000981:diagnostic imaging / Q000473:pathology; D004487:Edema / Q000473:pathology; D005260:Female; D005384:Finger Joint / Q000000981:diagnostic imaging / Q000473:pathology*; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000592:standards; D008297:Male; D008875:Middle Aged; D011859:Radiography; D012016:Reference Values; D013585:Synovitis / Q000000981:diagnostic imaging / Q000473:pathology*; D014955:Wrist Joint / Q000000981:diagnostic imaging / Q000473:pathology*