title: Angular malalignment as cause of limitation of forearm rotation: an analysis of prospectively collected data of both-bone forearm fractures in children.
abstract: BACKGROUND
  Although limitation of pronation/supination following both-bone forearm fractures in children is often attributed to an angular malunion, no clinical study has compared pronation/supination and angular malalignment of the same child by analysis of prospectively collected clinical data.
  
  
  OBJECTIVE
  The purpose of this trial is to explore whether limitation of pronation/supination can be predicted by the degree of angular malalignment in children who sustained a both-bone forearm fracture.
  
  
  METHODS
  In four Dutch hospitals, children aged ≤16 years with a both-bone forearm fracture were prospectively followed up consecutive children for 6-9 months. At the final follow-up, pronation/supination and angular malunion on radiographs were determined.
  
  
  RESULTS
  Between January 2006 and August 2010, a total of 410 children were prospectively followed up, of which 393 children were included for analysis in this study. The mean age of the children was 8.0 (±3.5) years, of which 63% were male and 40% fractured their dominant arm. The mean time to final examination was 219 (±51) days. Children with a metaphyseal both-bone fracture of the distal forearm with an angular malalignment of ≤15° had a 9-13% chance of developing a clinically relevant limitation (i.e., <50° of pronation and/or supination), while children with an angular malalignment of ≥16° had a 60% chance. Children with diaphyseal both-bone forearm fractures with ≤5° of angular malalignment had a 13% chance of developing a clinically relevant limitation, which showed no significant increase with a further increase of angular malalignment.
  
  
  CONCLUSIONS
  Children who sustained a both-bone forearm fracture localised in the distal metaphysis have a higher chance of developing a clinically relevant limitation of forearm rotation in case of a more severe angular malalignment, while children with a diaphyseal both-bone forearm fracture had a moderate chance of limitation, irrespective of the severity of the angular malalignment.
authors.affiliation: Erasmus Medical Center, Department of Orthopaedic Surgery, Westzeedijk 361, Postbus 2040, 3000 CA Rotterdam, The Netherlands. Electronic address: j.colaris@erasmusmc.nl.
authors.forename: Joost
authors.initials: J
authors.lastname: Colaris
authors.affiliation: Erasmus Medical Center, Department of Orthopaedic Surgery, Westzeedijk 361, Postbus 2040, 3000 CA Rotterdam, The Netherlands.
authors.forename: Max
authors.initials: M
authors.lastname: Reijman
authors.affiliation: Erasmus Medical Center, Department of Orthopaedic Surgery, Westzeedijk 361, Postbus 2040, 3000 CA Rotterdam, The Netherlands.
authors.forename: Jan Hein
authors.initials: JH
authors.lastname: Allema
authors.affiliation: Erasmus Medical Center, Department of Orthopaedic Surgery, Westzeedijk 361, Postbus 2040, 3000 CA Rotterdam, The Netherlands.
authors.forename: Mark
authors.initials: M
authors.lastname: de Vries
authors.affiliation: Erasmus Medical Center, Department of Orthopaedic Surgery, Westzeedijk 361, Postbus 2040, 3000 CA Rotterdam, The Netherlands.
authors.forename: Ulas
authors.initials: U
authors.lastname: Biter
authors.affiliation: Erasmus Medical Center, Department of Orthopaedic Surgery, Westzeedijk 361, Postbus 2040, 3000 CA Rotterdam, The Netherlands.
authors.forename: Rolf
authors.initials: R
authors.lastname: Bloem
authors.affiliation: Erasmus Medical Center, Department of Orthopaedic Surgery, Westzeedijk 361, Postbus 2040, 3000 CA Rotterdam, The Netherlands.
authors.forename: Cees
authors.initials: C
authors.lastname: van de Ven
authors.affiliation: Erasmus Medical Center, Department of Orthopaedic Surgery, Westzeedijk 361, Postbus 2040, 3000 CA Rotterdam, The Netherlands.
authors.forename: Jan
authors.initials: J
authors.lastname: Verhaar
mesh_terms: D000293:Adolescent; D001696:Biomechanical Phenomena; D002648:Child; D002675:Child, Preschool; D003625:Data Collection; D004185:Disability Evaluation; D004954:Esthetics; D005260:Female; D005543:Forearm Injuries / Q000000981:diagnostic imaging / Q000503:physiopathology*; D005594:Fracture Fixation, Intramedullary / Q000009:adverse effects / Q000379:methods*; D017759:Fractures, Malunited / Q000000981:diagnostic imaging / Q000503:physiopathology* / Q000601:surgery; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008279:Magnetic Resonance Imaging; D008297:Male; D009426:Netherlands; D011403:Pronation; D011446:Prospective Studies; D011885:Radius Fractures / Q000000981:diagnostic imaging / Q000503:physiopathology* / Q000601:surgery; D012399:Rotation; D013484:Supination; D014057:Tomography, X-Ray Computed; D016896:Treatment Outcome; D014458:Ulna Fractures / Q000000981:diagnostic imaging / Q000503:physiopathology* / Q000601:surgery
keywords: Angular malalignment; Both-bone forearm fractures; Children; Limitation of forearm rotation