title: Stress fracture of bilateral posterior facet after insertion of interspinous implant.
abstract: METHODS
  A case report of stress fracture of bilateral lumbar posterior facet after implantation of interspinous process device is reported and the literature reviewed. OBJECTIVE.: To report the rare case of stress fracture of bilateral lumbar posterior facet after implantation of interspinous process device.
  
  
  BACKGROUND
  A 64-year-old woman presented with severe back pain and radiating pain in both legs. In her history, she had undergone implantation of L4-L5 interspinous process device (Coflex, Paradigm Spine, Wurmlingen, Germany) for her neurogenic claudication at 6 years ago. Magnetic resonance image demonstrated signal change suggesting bilateral L4 inferior process. To the best of the authors' knowledge, there has been no report stress fracture of posterior facet after implantation of interspinous process device.
  
  
  METHODS
  This study reviewed the patient's medical record, her imaging studies, and related literatures.
  
  
  RESULTS
  In the reported case, stress fracture of bilateral posterior facet was documented with MRI and confirmed with surgical treatment for the surgical treatment of spinal stenosis. The involved facet joint was at the site affected by previously implanted interspinous process device.
  
  
  CONCLUSIONS
  Posterior facet fracture can occur as a complication of interspinous process device.
authors.affiliation: Department of Orthopaedic Surgery, Kangnam Sacred Heart Hospital, Hallym University, Seoul, Korea. chungkjmd@dreamwiz.com
authors.forename: Kook Jin
authors.initials: KJ
authors.lastname: Chung
authors.forename: Yoon Sub
authors.initials: YS
authors.lastname: Hwang
authors.forename: Sung Hye
authors.initials: SH
authors.lastname: Koh
mesh_terms: D001416:Back Pain / Q000209:etiology; D015984:Causality; D005260:Female; D015775:Fractures, Stress / Q000000981:diagnostic imaging / Q000209:etiology* / Q000473:pathology; D007839:Functional Laterality / Q000502:physiology; D006801:Humans; D007383:Intermittent Claudication / Q000209:etiology / Q000601:surgery; D016268:Internal Fixators / Q000009:adverse effects*; D008159:Lumbar Vertebrae / Q000000981:diagnostic imaging / Q000293:injuries* / Q000473:pathology; D008875:Middle Aged; D011128:Polyradiculopathy / Q000209:etiology / Q000503:physiopathology / Q000601:surgery; D011183:Postoperative Complications / Q000000981:diagnostic imaging / Q000209:etiology / Q000473:pathology; D019736:Prostheses and Implants / Q000009:adverse effects; D011859:Radiography; D016103:Spinal Fractures / Q000000981:diagnostic imaging / Q000209:etiology* / Q000473:pathology; D013123:Spinal Fusion / Q000009:adverse effects* / Q000295:instrumentation / Q000379:methods; D013126:Spinal Nerve Roots / Q000293:injuries / Q000473:pathology / Q000503:physiopathology; D013130:Spinal Stenosis / Q000150:complications / Q000503:physiopathology / Q000601:surgery; D013314:Stress, Mechanical; D016474:Weight-Bearing / Q000502:physiology; D021801:Zygapophyseal Joint / Q000293:injuries* / Q000473:pathology