title: Association between joint hypermobility, scoliosis, and cranial base anomalies in paediatric Osteogenesis imperfecta patients: a retrospective cross-sectional study.
abstract: BACKGROUND
  Joint hypermobility is a common clinical characteristic of patients with Osteogenesis imperfecta (OI), a disorder with serious comorbidities of scoliosis and cranial base anomalies. This study aimed at evaluating how prevalent joint hypermobility is in paediatric OI patients, and to find out whether it serves as a potential predictive marker of the different spinal complications; scoliosis and craniovertebral anomalies (basilar impression and basilar invagination).
  
  
  METHODS
  In this cross-sectional one-center study we analysed retrospectively clinical patient records and radiographs of 47 OI patients, aged 1-19 years, some of whom were treated with bisphosphonates. Presence of joint hypermobility, scoliosis, and craniovertebral anomalies was recorded and possible connections between the phenomena were explored with correlation analysis.
  
  
  RESULTS
  Joint hypermobility was found in 70% of the patients. Scoliosis and cranial base anomalies had developed in 26%. The presence of spinal complications was independent of the bisphosphonate treatment status and joint hypermobility.
  
  
  CONCLUSIONS
  Scoliosis and craniovertebral anomalies are strongly associated in paediatric OI patients. Joint hypermobility that is much more common appears, however, to be a poor predictor.
authors.affiliation: Department of Orthodontics, Institute of Dentistry, University of Helsinki, PO Box 41, FI-00014 Helsinki, Finland. heidi.arponen@fimnet.fi.
authors.forename: Heidi
authors.initials: H
authors.lastname: Arponen
authors.forename: Outi
authors.initials: O
authors.lastname: Mäkitie
authors.forename: Janna
authors.initials: J
authors.lastname: Waltimo-Sirén
mesh_terms: D000293:Adolescent; D002648:Child; D002675:Child, Preschool; D003430:Cross-Sectional Studies; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D007593:Joint Instability / Q000175:diagnosis / Q000453:epidemiology*; D008137:Longitudinal Studies; D008297:Male; D010013:Osteogenesis Imperfecta / Q000175:diagnosis / Q000453:epidemiology*; D012189:Retrospective Studies; D012600:Scoliosis / Q000175:diagnosis / Q000453:epidemiology*; D019291:Skull Base / Q000002:abnormalities* / Q000473:pathology