title: Risk factors for spinal epidural hematoma after spinal surgery.
abstract: METHODS
  A case-control retrospective analysis comparing patients who developed a postoperative spinal epidural hematoma with patients who did not develop this complication.
  
  
  OBJECTIVE
  To identify risk factors for the development of an epidural hematoma following spinal surgery.
  
  
  BACKGROUND
  Neurologic deterioration following spinal surgery is a rare but devastating complication. Epidural hematomas should be suspected in the patient who demonstrates a new postoperative neurologic deficit. The risk factors that predispose a patient to a postoperative spinal epidural hematoma have not been identified.
  
  
  METHODS
  Patients who underwent spinal surgery at a single institution over a 10-year period were retrospectively reviewed. Twelve patients who demonstrated neurologic deterioration after surgery and required surgical decompression because of an epidural hematoma were identified. All cases involved lumber laminectomies. A total of 404 consecutive patients that underwent lumbar decompression and did not develop an epidural hematoma formed the control group. Factors postulated to increase the risk of postoperative spinal epidural hematoma were compared between the two groups using logistic regression.
  
  
  RESULTS
  Multilevel procedures (P = 0.037) and the presence of a preoperative coagulopathy (P < 0.001) were significant risk factors. Age, body mass index, perioperative durotomies, and postoperative drains were not statistically significant risk factors.
  
  
  CONCLUSIONS
  Patients who require multilevel lumbar procedures and/or have a preoperative coagulopathy are at a significantly higher risk for developing a postoperative epidural hematoma.
authors.affiliation: Department of Orthopaedic Surgery, William Beaumont Hospital, Royal Oak, Michigan, USA.
authors.forename: J
authors.initials: J
authors.lastname: Kou
authors.forename: J
authors.initials: J
authors.lastname: Fischgrund
authors.forename: A
authors.initials: A
authors.lastname: Biddinger
authors.forename: H
authors.initials: H
authors.lastname: Herkowitz
mesh_terms: D001778:Blood Coagulation Disorders / Q000453:epidemiology; D016022:Case-Control Studies; D015984:Causality; D015897:Comorbidity; D006407:Hematoma, Epidural, Cranial / Q000453:epidemiology / Q000209:etiology*; D006801:Humans; D015994:Incidence; D007796:Laminectomy / Q000009:adverse effects*; D016015:Logistic Models; D008161:Lumbosacral Region; D016017:Odds Ratio; D011183:Postoperative Complications / Q000453:epidemiology; D012189:Retrospective Studies; D018570:Risk Assessment; D012307:Risk Factors; D013118:Spinal Cord Diseases / Q000453:epidemiology / Q000209:etiology*; D013131:Spine / Q000601:surgery*