title: Significance of clinical evaluation of the metacarpophalangeal joint in relation to synovial/bone pathology in rheumatoid and psoriatic arthritis detected by magnetic resonance imaging.
abstract: OBJECTIVE
  Rheumatologists base many clinical decisions regarding the management of inflammatory joint diseases on joint counts performed at clinic. We investigated the reliability and accuracy of physically examining the metacarpophalangeal (MCP) joints to detect inflammatory synovitis using magnetic resonance imaging (MRI) as the gold standard.
  
  
  METHODS
  MCP joints 2 to 5 in both hands of 5 patients with rheumatoid arthritis (RA) and 5 with psoriatic arthritis (PsA) were assessed by 5 independent examiners for joint-line swelling (visually and by palpation); joint-line tenderness by palpation (tender joint count, TJC) and stress pain; and by MRI (1.5 Tesla superconducting magnet). Interrater reliability was assessed using kappa statistics, and agreement between examination and corresponding MRI assessment was assessed by Fisher's exact tests (p < 0.05 considered statistically significant).
  
  
  RESULTS
  Interrater agreement was highest for visual assessment of swelling (kappa = 0.55-0.63), slight-fair for assessment of swelling by palpation (kappa = 0.19-0.41), and moderate (kappa = 0.41-0.58) for assessment of joint tenderness. In patients with RA, TJC, stress pain, and visual swelling assessment were strongly associated with MRI evaluation of synovitis. Visual swelling assessment demonstrated high specificity (> 0.8) and positive predictive value (= 0.8). For PsA, significant associations exist between TJC and MRI synovitis scores (p < 0.01) and stress pain and MRI edema scores (p < 0.04). Assessment of swelling by palpation was not significantly associated with synovitis or edema as determined by MRI in RA or PsA (p = 0.54-1.0).
  
  
  CONCLUSIONS
  In inflammatory arthritis, disease activity in MCP joints can be reliably assessed at the bedside by examining for joint-line tenderness (TJC) and visual inspection for swelling. Clinical assessment may have to be complemented by other methods for evaluating disease activity in the joint, such as MRI, particularly in patients with PsA.
authors.affiliation: University of Toronto, Mount Sinai Hospital, Toronto, Ontario, Canada.
authors.forename: Millicent A
authors.initials: MA
authors.lastname: Stone
authors.forename: Lawrence M
authors.initials: LM
authors.lastname: White
authors.forename: Dafna D
authors.initials: DD
authors.lastname: Gladman
authors.forename: Robert D
authors.initials: RD
authors.lastname: Inman
authors.forename: Sam
authors.initials: S
authors.lastname: Chaya
authors.forename: Matthew
authors.initials: M
authors.lastname: Lax
authors.forename: David
authors.initials: D
authors.lastname: Salonen
authors.forename: Deborah A
authors.initials: DA
authors.lastname: Weber
authors.forename: Judy A
authors.initials: JA
authors.lastname: Guthrie
authors.forename: Emma
authors.initials: E
authors.lastname: Pomeroy
authors.forename: Dominik
authors.initials: D
authors.lastname: Podbielski
authors.forename: Edward C
authors.initials: EC
authors.lastname: Keystone
mesh_terms: D015535:Arthritis, Psoriatic / Q000276:immunology / Q000473:pathology*; D001172:Arthritis, Rheumatoid / Q000276:immunology / Q000473:pathology*; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods; D008662:Metacarpophalangeal Joint / Q000473:pathology*; D013585:Synovitis / Q000276:immunology / Q000473:pathology*