title: Preliminary comparison of primary and conversion surgery with magnetically controlled growing rods in children with early onset scoliosis.
abstract: Non-invasive distraction of magnetically controlled growing rods (MCGR) avoids repeated surgical lengthening in patients with early onset scoliosis, but it is not known how effective this technique is in previously operated children.
  
  
  
  In a retrospective, multicentre study, the data were obtained for 27 primary (P) patients [mean age 7.0 (2.4-10.7) years at surgery] and 23 conversion (C) patients [mean age 7.7 (3.6-11.0) years at conversion from standard growing rods] with 1-year follow-up.
  
  
  
  The mean major curve was 63.9° in the P group and 46.5° in the C group at baseline (preoperatively, p = 0.0009) and 39.5° and 39.6°, respectively, at 1-year follow-up (p = 0.99). The mean percentage change of spinal growth from baseline to 1-year follow-up was 18.3 % in the P group and 6.5 % in the C group (p = 0.007). Comparing the spinal growth from postoperative to 1-year follow-up no statistical difference was observed between the study groups (1.8 % P vs -2.2 % C, p = 0.09).
  
  
  
  Scoliosis can be equally controlled after conversion from traditional growing rods into MCGR, but spinal growth from baseline is less in the conversion patients as compared with the primary group.
  
  
  
  III.
authors.affiliation: Department of Paediatric Orthopaedic Surgery, University of Turku and Turku University Hospital, Kiinamyllynkatu 4-8, 20521, Turku, Finland.
authors.forename: Heli
authors.initials: H
authors.lastname: Keskinen
authors.affiliation: Department of Paediatric Orthopaedic Surgery, University of Turku and Turku University Hospital, Kiinamyllynkatu 4-8, 20521, Turku, Finland. ilkka.helenius@utu.fi.
authors.forename: Ilkka
authors.initials: I
authors.lastname: Helenius
authors.affiliation: Spine Unit, Oxford University Hospital, Oxford, UK.
authors.forename: Colin
authors.initials: C
authors.lastname: Nnadi
authors.affiliation: Department of Orthopaedic Surgery, The University of Hong Kong, Pokfulam, Hong Kong.
authors.forename: Kenneth
authors.initials: K
authors.lastname: Cheung
authors.affiliation: Starship Children's Hospital, 2 Park Rod, Grafton, Auckland, New Zealand.
authors.forename: J
authors.initials: J
authors.lastname: Ferguson
authors.affiliation: San Diego Center for Spinal Disorders, La Jolla, CA, USA.
authors.forename: Gregory
authors.initials: G
authors.lastname: Mundis
authors.affiliation: San Diego Center for Spinal Disorders, La Jolla, CA, USA.
authors.forename: Jeff
authors.initials: J
authors.lastname: Pawelek
authors.affiliation: San Diego Center for Spinal Disorders, La Jolla, CA, USA.
authors.forename: Behrooz A
authors.initials: BA
authors.lastname: Akbarnia
mesh_terms: D002648:Child; D002675:Child, Preschool; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D059346:Magnets; D008297:Male; D019857:Osteogenesis, Distraction / Q000295:instrumentation / Q000379:methods*; D012189:Retrospective Studies; D012600:Scoliosis / Q000601:surgery*; D016896:Treatment Outcome
keywords: Deformity correction; Early onset scoliosis; Magnetic growing rods; Revision surgery; Spinal growth