title: Ulnar styloid process nonunion and outcome in patients with a distal radius fracture: a meta-analysis of comparative clinical trials.
abstract: OBJECTIVE
  There is no consensus on the relation between ulnar styloid process nonunion and outcome in patients with distal radius fractures. The aim of this study was to analyze whether patient-reported outcome is influenced by the nonunion of the accompanying ulnar styloid fracture in distal radius fracture patients.
  
  
  METHODS
  A meta-analysis of published studies comparing outcomes after distal radius fractures with a united versus a non-united ulnar styloid process was performed. In addition, if provided by the authors, the raw data of these studies were pooled and analysed as one study. The outcome measures of the analyses included patient-reported outcome, functional outcome, grip-strength, pain, and distal radioulnar joint (DRUJ) instability.
  
  
  RESULTS
  Data from six comparative studies were included, concerning 365 patients with a distal radius fracture. One hundred and thirty-five patients with an ulnar styloid union were compared with 230 patients with a nonunion of the ulnar styloid. No significant differences were found between groups regarding any outcome measure.
  
  
  CONCLUSIONS
  Based on this meta-analysis, there is no relation between the nonunion of the ulnar styloid process and function in patients with a distal radius fracture.
authors.affiliation: Department of Surgery-Traumatology, Leiden University Medical Center, Leiden, The Netherlands. Electronic address: M.M.E.Wijffels@lumc.nl.
authors.forename: M M E
authors.initials: MM
authors.lastname: Wijffels
authors.affiliation: Department of Surgery-Traumatology, Leiden University Medical Center, Leiden, The Netherlands.
authors.forename: J
authors.initials: J
authors.lastname: Keizer
authors.affiliation: Department of Orthopedic Surgery, Academic Medical Center, Amsterdam, The Netherlands.
authors.forename: G A
authors.initials: GA
authors.lastname: Buijze
authors.affiliation: Department of Orthopaedic Surgery, University of Occupational and Environmental Health, Fukuoka, Japan.
authors.forename: Y
authors.initials: Y
authors.lastname: Zenke
authors.affiliation: Department of Surgery-Traumatology, Leiden University Medical Center, Leiden, The Netherlands.
authors.forename: P
authors.initials: P
authors.lastname: Krijnen
authors.affiliation: Department of Surgery, Academic Medical Center Amsterdam, Amsterdam, The Netherlands.
authors.forename: N W L
authors.initials: NW
authors.lastname: Schep
authors.affiliation: Department of Surgery-Traumatology, Leiden University Medical Center, Leiden, The Netherlands.
authors.forename: I B
authors.initials: IB
authors.lastname: Schipper
mesh_terms: D002986:Clinical Trials as Topic; D005593:Fracture Fixation, Internal; D017102:Fracture Healing; D017759:Fractures, Malunited / Q000503:physiopathology / Q000601:surgery*; D006801:Humans; D007593:Joint Instability / Q000473:pathology*; D010147:Pain Measurement; D011885:Radius Fractures / Q000503:physiopathology / Q000601:surgery*; D016059:Range of Motion, Articular; D020127:Recovery of Function; D016896:Treatment Outcome; D014458:Ulna Fractures / Q000503:physiopathology / Q000601:surgery*; D014955:Wrist Joint / Q000503:physiopathology*
keywords: Distal radioulnar joint instability; Distal radius fracture; Nonunion; Outcome; Ulnar styloid process; Wrist fracture