title: Iatrogenic fractures in ankylosing spondylitis--a report of two cases.
abstract: METHODS
  Two cases of intraoperative, iatrogenic cervical spine fractures in patients with ankylosing spondylitis are reported.
  
  
  OBJECTIVE
  To describe the uncommon complication of iatrogenic cervical spine fractures occurring during spine surgery in patients with ankylosing spondylitis.
  
  
  BACKGROUND
  To our knowledge, this is the first report on this rare complication.
  
  
  METHODS
  A 39-year-old patient (1) with ankylosing spondylitis was operated on for cervical stenosis due to C1/2 anterolisthesis. Fifteen hours postoperatively, he developed acute quadriplegia. MRI revealed a fracture/dislocation of C6 on C7 and compression of the spinal cord at this level. Revision was performed with decompression and instrumentation from the occiput to T3. A 55-year-old patient (2) with ankylosing spondylitis and thoracic hyperkyphosis underwent a correction procedure consisting of costotransversectomy, anterior cage implantation at T8/9, and posterior instrumentation from T4 to L1. Halo traction was temporarily applied for correction. At the end of the operation, with the patient still under anesthesia, increased mobility of the cervical spine was noticed. Emergent MRI revealed a fracture of the anterior structures of C6/7. Posterior instrumentation from C5 to T1 was then performed.
  
  
  RESULTS
  Quadriplegia persisted in patient 1 until his death secondary to further complications. Patient 2 was mobilized without any neurologic deficits. The fracture healed in good alignment.
  
  
  CONCLUSIONS
  Iatrogenic fractures of the cervical spine during surgery in ankylosing spondylitis patients are a rare but potentially severe complication. Early diagnosis and therapy are necessary before dislocation, cord compression, and subsequent neurologic impairment occur.
authors: Department of Orthopedics and Traumatology, Center for Spinal Surgery, Klinikum Karlsbad-Langensteinbach, Guttmannstr. 1, 76307 Karlsbad, Germany. michael.ruf@kkl.srh.de
authors: Michael
authors: M
authors: Ruf
authors: Sascha
authors: S
authors: Rehm
authors: Christiane
authors: C
authors: Poeckler-Schoeniger
authors: Harry R
authors: HR
authors: Merk
authors: Juergen
authors: J
authors: Harms
mesh_terms: D000328:Adult; D002574:Cervical Vertebrae; D019299:Decompression, Surgical / Q000379:methods*; D005500:Follow-Up Studies; D006801:Humans; D007049:Iatrogenic Disease; D007431:Intraoperative Complications / Q000175:diagnosis / Q000601:surgery; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D012086:Reoperation; D018570:Risk Assessment; D012720:Severity of Illness Index; D016103:Spinal Fractures / Q000175:diagnosis / Q000209:etiology* / Q000601:surgery; D013130:Spinal Stenosis / Q000175:diagnosis / Q000209:etiology / Q000601:surgery*; D013167:Spondylitis, Ankylosing / Q000150:complications* / Q000175:diagnosis; D016896:Treatment Outcome