title: Traumatic L4-5 bilateral locked facet joints.
abstract: Traumatic bilateral locked facet joints occur with extreme rarity in the lumbar spine. A careful review of the literature revealed only three case reports.
  
  
  
  We present the case of a 36 year-old male who suffered bilateral L4-5 facet fracture dislocations following a motor vehicle collision. The dislocation was associated with disruption of the posterior elements and a Grade II anterolisthesis of L4 on L5 as well as an epidural hematoma resulting in severe canal narrowing, with the patient remaining neurologically intact on presentation. The patient underwent open reduction with L3 to S1 pedicle screw fixation and arthrodesis to treat this highly unstable injury.
  
  
  
  The existing literature and a biomechanics review of the lumbar spine are described in the context of the presented case in addition to a proposed mechanism for such dislocations.
authors.affiliation: Department of Neurological Surgery, University of Pittsburgh Medical Center, Suite B-400, 200 Lothrop Street, Pittsburgh, PA, 15213, USA.
authors.forename: Georgios A
authors.initials: GA
authors.lastname: Zenonos
authors.affiliation: Department of Neurological Surgery, University of Pittsburgh Medical Center, Suite B-400, 200 Lothrop Street, Pittsburgh, PA, 15213, USA.
authors.forename: Nitin
authors.initials: N
authors.lastname: Agarwal
authors.affiliation: Department of Neurological Surgery, University of Pittsburgh Medical Center, Suite B-400, 200 Lothrop Street, Pittsburgh, PA, 15213, USA.
authors.forename: Edward A
authors.initials: EA
authors.lastname: Monaco
authors.affiliation: Department of Neurological Surgery, University of Pittsburgh Medical Center, Suite B-400, 200 Lothrop Street, Pittsburgh, PA, 15213, USA.
authors.forename: David O
authors.initials: DO
authors.lastname: Okonkwo
authors.affiliation: Department of Neurological Surgery, University of Pittsburgh Medical Center, Suite B-400, 200 Lothrop Street, Pittsburgh, PA, 15213, USA. kanteras@upmc.edu.
authors.forename: Adam S
authors.initials: AS
authors.lastname: Kanter
mesh_terms: D000063:Accidents, Traffic; D000328:Adult; D000072039:Fracture Dislocation / Q000209:etiology* / Q000601:surgery; D046748:Hematoma, Epidural, Spinal / Q000209:etiology / Q000601:surgery; D006801:Humans; D008159:Lumbar Vertebrae / Q000293:injuries* / Q000601:surgery; D008297:Male; D021801:Zygapophyseal Joint / Q000293:injuries* / Q000601:surgery
keywords: Bilateral locked facet joints; Pedicle screw fixation; Spinal biomechanics