title: MRI of the wrist in juvenile idiopathic arthritis: erosions or normal variants? A prospective case-control study.
abstract: BACKGROUND
  Bony depressions at the wrist resembling erosions are frequently seen on MRI in healthy children. The accuracy of MRI in detecting early bony destruction is therefore questionable. We compared findings on MRI of the wrist in healthy children and those with juvenile idiopathic arthritis (JIA) to investigate markers for true disease.
  
  
  METHODS
  We compared the number and localisation of bony depressions at the wrist in 85 healthy children and 68 children with JIA, ages 5-15 years. The size of the wrist was assessed from a radiograph of the wrist performed on the same day as the MRI.
  
  
  RESULTS
  No significant difference in the number of bony depressions in the carpal bones was seen between healthy children and children with JIA at any age. Depressions are found in similar locations in the two groups, except for a few sites, where bony depressions were seen exclusively in the JIA group, particularly at the CMC joints. The wrist was significantly smaller in children with JIA (P < 0.001).
  
  
  CONCLUSIONS
  Using adult scoring systems and standard MR sequences in the assessment of bone destruction in children may lead to overstaging or understaging of disease. At present, standard MRI sequences cannot easily be used for assessment of early signs of erosions in children.
authors.affiliation: Department of Radiology, University Hospital North Norway, Tromsø, Norway. lil-sofie.ording@unn.no
authors.forename: Lil-Sofie
authors.initials: LS
authors.lastname: Ording Muller
authors.forename: Peter
authors.initials: P
authors.lastname: Boavida
authors.forename: Derk
authors.initials: D
authors.lastname: Avenarius
authors.forename: Beatrice
authors.initials: B
authors.lastname: Damasio
authors.forename: Odd Petter
authors.initials: OP
authors.lastname: Eldevik
authors.forename: Clara
authors.initials: C
authors.lastname: Malattia
authors.forename: Karen
authors.initials: K
authors.lastname: Lambot-Juhan
authors.forename: Laura
authors.initials: L
authors.lastname: Tanturri
authors.forename: Catherine M
authors.initials: CM
authors.lastname: Owens
authors.forename: Karen
authors.initials: K
authors.lastname: Rosendahl
mesh_terms: D000293:Adolescent; D001171:Arthritis, Juvenile / Q000453:epidemiology* / Q000473:pathology*; D016022:Case-Control Studies; D002648:Child; D002675:Child, Preschool; D003937:Diagnosis, Differential; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods* / Q000706:statistics & numerical data*; D008297:Male; D009664:Norway / Q000453:epidemiology; D015995:Prevalence; D011446:Prospective Studies; D012016:Reference Values; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D014955:Wrist Joint / Q000002:abnormalities* / Q000473:pathology*