title: Lumbar chance fracture in an adult snowboarder: unusual mechanism of a chance fracture.
abstract: METHODS
  A case of a Chance fracture in an adult snowboarder following a fall is presented. The mechanism of this fracture is reported.
  
  
  OBJECTIVE
  To increase awareness of the spinal injuries in snowboarders and to propose the mechanism of this unusual fracture.
  
  
  BACKGROUND
  Chance fractures rarely occur in adults and are very unusual in children. Nearly all of the reported cases are in conjunction with lap-type seat belt injuries. To the authors' knowledge, this is the first reported case of a lumbar Chance fracture in an adult snowboarder.
  
  
  METHODS
  A 25-year-old snowboarder sustained an L1 Chance fracture following a fall backward. The patient was placed in a hyperextension cast, and the cast was changed to a thoracolumbar orthosis after 12 weeks.
  
  
  RESULTS
  Complete bony union was obtained with body cast immobilization, and an excellent functional restoration was obtained.
  
  
  CONCLUSIONS
  Chance fractures are horizontal splitting fractures of the posterior elements of the vertebrae, and the mechanism of the injury is that of a hyperflexion of the spine over a fulcrum. A Chance-type fracture can be seen in an adult snowboarder, when acute hyperflexion of the spine occurs following a fall backward.
authors.affiliation: Department of Orthopedic Surgery, Kanebo Memorial Hospital, Japan.
authors.forename: Koji
authors.initials: K
authors.lastname: Okamoto
authors.forename: Minoru
authors.initials: M
authors.lastname: Doita
authors.forename: Masaho
authors.initials: M
authors.lastname: Yoshikawa
authors.forename: Michihiko
authors.initials: M
authors.lastname: Manabe
authors.forename: Norihide
authors.initials: N
authors.lastname: Sha
authors.forename: Shinichi
authors.initials: S
authors.lastname: Yoshiya
mesh_terms: D000058:Accidental Falls; D000328:Adult; D001265:Athletic Injuries / Q000000981:diagnostic imaging / Q000209:etiology* / Q000628:therapy; D002370:Casts, Surgical; D005596:Fractures, Closed / Q000000981:diagnostic imaging / Q000209:etiology* / Q000628:therapy; D006801:Humans; D007103:Immobilization; D008159:Lumbar Vertebrae / Q000000981:diagnostic imaging / Q000293:injuries*; D008297:Male; D038161:Snow Sports / Q000293:injuries*; D016103:Spinal Fractures / Q000000981:diagnostic imaging / Q000209:etiology* / Q000628:therapy; D014057:Tomography, X-Ray Computed; D016896:Treatment Outcome