title: Musculoskeletal ultrasonography in healthy subjects and ultrasound criteria for early arthritis (the ESPOIR cohort).
abstract: OBJECTIVE
  To confirm the occurrence of bone erosions and synovitis in healthy subjects detectable by ultrasound (US) and to establish US criteria for early arthritis.
  
  
  METHODS
  Our study involved 127 healthy subjects matched with a cohort of patients with early arthritis (the ESPOIR cohort). The second and fifth metacarpophalangeal (MCP) joints and the fifth metatarsophalangeal (MTP) joint of both hands and feet were assessed with US to detect bone erosion; and the second, third, fourth, and fifth MCP and the fifth MTP were evaluated for synovial thickening in B-mode US and synovial vascularity in power Doppler. Bone erosion and synovitis were defined according to the Outcome Measures in Rheumatology Clinical Trials consensus.
  
  
  RESULTS
  Bone erosion and grade 2-3 synovial thickening in B-mode were detected in 11% and 9% of healthy subjects. To consider the diagnosis of early arthritis, a cutoff at 1 case of synovial thickening in B-mode enabled discrimination between patients with early arthritis and healthy subjects, with a good sensitivity of 74.8% (95% CI 67.2%-82.3%) and a high specificity of 90.5% (95% CI 85.4%-95.6%). If higher specificity is required to confirm the diagnosis of early arthritis, cutoff at 2 cases of synovial thickening in B-mode or at 2 cases of bone erosion gave optimal results, with specificity of 98.4% (95% CI 96.2%-100%) and 100%, respectively, and lower sensitivity of 59.8% (95% CI 51.2%-68.3%) and 17% (95% CI 10.5%-23.5%) (area under the curve = 0.85 for synovitis and 0.63 for bone erosion). Neither the combination of power Doppler signal plus bone erosion, nor bone erosions plus synovial thickening on the same joint, were seen in healthy subjects.
  
  
  CONCLUSIONS
  A single case of bone erosion or synovial thickening in B-mode is common in healthy subjects. However, more than 1 case of synovial thickening in B-mode or bone erosion is a strong argument for the diagnosis of early inflammatory arthritis.
authors.affiliation: CHU Amiens - Rheumatology, Place Victor Pauchet, Amiens 80000, France. millot.florence@chu-amiens.fr
authors.forename: Florence
authors.initials: F
authors.lastname: Millot
authors.forename: Gaëlle
authors.initials: G
authors.lastname: Clavel
authors.forename: Fabien
authors.initials: F
authors.lastname: Etchepare
authors.forename: Frédérique
authors.initials: F
authors.lastname: Gandjbakhch
authors.forename: Franck
authors.initials: F
authors.lastname: Grados
authors.forename: Alain
authors.initials: A
authors.lastname: Saraux
authors.forename: Anne-Christine
authors.initials: AC
authors.lastname: Rat
authors.forename: Bruno
authors.initials: B
authors.lastname: Fautrel
authors.forename: Pierre
authors.initials: P
authors.lastname: Bourgeois
authors.forename: Patrice
authors.initials: P
authors.lastname: Fardellone
mesh_terms: D001168:Arthritis / Q000175:diagnosis / Q000000981:diagnostic imaging* / Q000473:pathology; D001842:Bone and Bones / Q000000981:diagnostic imaging / Q000473:pathology; D016022:Case-Control Studies; D002986:Clinical Trials as Topic; D005260:Female; D005528:Foot / Q000033:anatomy & histology; D006225:Hand / Q000033:anatomy & histology; D006801:Humans; D007596:Joints / Q000000981:diagnostic imaging* / Q000473:pathology; D008297:Male; D008875:Middle Aged; D012372:ROC Curve; D011859:Radiography; D013585:Synovitis / Q000175:diagnosis / Q000000981:diagnostic imaging* / Q000473:pathology; D014463:Ultrasonography