title: Bone health of patients with juvenile idiopathic arthritis: a comparison between dual-energy X-ray absorptiometry and digital X-ray radiogrammetry.
abstract: OBJECTIVE
  Juvenile idiopathic arthritis (JIA) affects bone mineral density (BMD). Dual-energy X-ray absorptiometry (DXA) is the most widely used technique to determine BMD. Digital X-ray radiogrammetry (DXR) is a feasible method for determination of cortical BMD on hand radiographs. This study aimed to compare DXR and DXA in the assessment of BMD in JIA patients.
  
  
  METHODS
  Thirty-five JIA patients with available DXA and hand radiograph within the same time period were included from the Dutch Arthritis and Biologicals in Children register. Outcome measures for BMD were Bone Health Index from DXR and BMD total body, BMD lumbar spine and Bone Mineral Apparent Density from DXA. All measures were transformed to Z-scores. Correlations were assessed with Pearson correlation coefficients.
  
  
  RESULTS
  Median age of the patients (60% female) was 11.7 years. Pearson correlation coefficient was significant for the absolute scores: 0.568-0.770 (p<0.001). No significant correlation was found between the Z-scores of DXA and DXR.
  
  
  CONCLUSIONS
  The BMD assessment from the DXR was correlated to DXA measures in a cohort of JIA patients, although only in absolute scores. Future steps for implementation of DXR in clinical practice include evaluation of responsiveness to change, predictive value and comparison with other imaging techniques.
authors.affiliation: Department of Radiology, Academic Medical Center, Meibergdreef 9, Amsterdam, The Netherlands; Department of Paediatric Haematology, Immunology, Rheumatology and Infectious Disease, Emma Children's Hospital, Academic Medical Center, Meibergdreef 9, Amsterdam, The Netherlands. Electronic address: c.m.nusman@amc.nl.
authors.forename: Charlotte M
authors.initials: CM
authors.lastname: Nusman
authors.affiliation: Department of Paediatrics/Paediatric Rheumatology, Sophia Children's Hospital, Erasmus MC, Wytemaweg 80, Rotterdam, The Netherlands.
authors.forename: Janneke
authors.initials: J
authors.lastname: Anink
authors.affiliation: Department of Paediatrics/Paediatric Rheumatology, Sophia Children's Hospital, Erasmus MC, Wytemaweg 80, Rotterdam, The Netherlands.
authors.forename: Marieke H
authors.initials: MH
authors.lastname: Otten
authors.affiliation: Department of Paediatric Haematology, Immunology, Rheumatology and Infectious Disease, Emma Children's Hospital, Academic Medical Center, Meibergdreef 9, Amsterdam, The Netherlands; Department of Paediatric Rheumatology, Reade Institute, Dr. Jan van Breemenstraat 2, Amsterdam, The Netherlands.
authors.forename: Marion A J
authors.initials: MA
authors.lastname: van Rossum
authors.affiliation: Department of Radiology, Academic Medical Center, Meibergdreef 9, Amsterdam, The Netherlands.
authors.forename: Rick R
authors.initials: RR
authors.lastname: van Rijn
authors.affiliation: Department of Radiology, Academic Medical Center, Meibergdreef 9, Amsterdam, The Netherlands.
authors.forename: Mario
authors.initials: M
authors.lastname: Maas
authors.affiliation: Department of Paediatrics/Paediatric Rheumatology, Sophia Children's Hospital, Erasmus MC, Wytemaweg 80, Rotterdam, The Netherlands.
authors.forename: Lisette W A
authors.initials: LW
authors.lastname: van Suijlekom-Smit
mesh_terms: D015502:Absorptiometry, Photon / Q000379:methods* / Q000706:statistics & numerical data; D000365:Age Determination by Skeleton / Q000379:methods; D001171:Arthritis, Juvenile / Q000000981:diagnostic imaging*; D015519:Bone Density / Q000502:physiology*; D002648:Child; D002675:Child, Preschool; D015331:Cohort Studies; D005260:Female; D006801:Humans; D008159:Lumbar Vertebrae / Q000000981:diagnostic imaging; D008297:Male; D050279:Metacarpal Bones / Q000000981:diagnostic imaging; D011237:Predictive Value of Tests; D011856:Radiographic Image Enhancement / Q000379:methods*; D051598:Whole Body Imaging / Q000379:methods
keywords: Bone density; Dual-energy X-ray absorptiometry; Etanercept; Juvenile idiopathic arthritis; Radiography