title: Avascular necrosis of lumbar facet joints associated with bilateral facet fractures.
abstract: BACKGROUND
  Avascular necrosis is a commonly described condition caused by a disruption of blood supply to the bones, resulting in necrosis. Although common in joints of the extremities, it is seen less often in the spine. Risk factors for avascular necrosis include steroid use, alcohol consumption, smoking, scuba diving, thrombosis, hypercoagulability, and hypertension.
  
  
  OBJECTIVE
  The purpose was to report an unprecedented case of avascular necrosis of the lumbar facet joints and bilateral facet fractures.
  
  
  METHODS
  This is a case report.
  
  
  METHODS
  The patient underwent L3-S1 decompression and L5-S1 discectomy, during which time avascular necrosis of the superior articular process of the L3-L4 facet joints was discovered. The patient then underwent spinal fusion with pedicle screw instrumentation. Pathologic examination of both right and left facet joints confirmed the diagnosis of avascular necrosis.
  
  
  RESULTS
  At 19-month follow up, the patient's leg and back pain had significantly improved. His spine appeared fused with no instability or implant failure.
  
  
  CONCLUSIONS
  We have presented a case of avascular necrosis of L3-L4 facet joints resulting in fracture and instability at the L3-L4 level of the spine, which was stabilized with an L3-L4 pedicle screw spinal fusion.
authors.affiliation: Texas Back Institute and Texas Back Institute Research Foundation, Plano, 6020 West Parker Road #200, Plano, TX 75093, USA. rbosita@texasback.com
authors.forename: Renato V
authors.initials: RV
authors.lastname: Bosita
authors.forename: Tiffany
authors.initials: T
authors.lastname: Hong
authors.forename: Donna D
authors.initials: DD
authors.lastname: Ohnmeiss
mesh_terms: D000328:Adult; D017586:Diskectomy; D006801:Humans; D007593:Joint Instability / Q000000981:diagnostic imaging* / Q000209:etiology / Q000601:surgery; D017116:Low Back Pain / Q000000981:diagnostic imaging* / Q000209:etiology / Q000601:surgery; D008159:Lumbar Vertebrae / Q000000981:diagnostic imaging* / Q000601:surgery; D008297:Male; D010020:Osteonecrosis / Q000150:complications / Q000000981:diagnostic imaging* / Q000601:surgery; D011859:Radiography; D016103:Spinal Fractures / Q000000981:diagnostic imaging* / Q000209:etiology / Q000601:surgery; D013123:Spinal Fusion