title: The Incidence of Durotomy and its Clinical and Economic Impact in Primary, Short-segment Lumbar Fusion: An Analysis of 17,232 Cases.
abstract: METHODS
  Retrospective database analysis.
  
  
  OBJECTIVE
  To determine the incidence of durotomy in primary short-segment lumbar fusion and assess its clinical and economic impacts.
  
  
  BACKGROUND
  The incidence of durotomy during primary lumbar fusion and its economic impact are not well described.
  
  
  METHODS
  The Nationwide Inpatient Sample was queried for all primary 1- or 2-level lumbar fusions performed in adults for lumbar spinal stenosis between 2009 and 2011; only elective cases without concurrent diagnoses of vertebral infection, fracture, or tumor were included. χ and t-tests were used as appropriate to compare categorical and continuous variables, respectively. Multivariate regression analysis was performed to identify factors independently associated with incidental durotomy, as well as total hospital charges, costs, and length of stay.
  
  
  RESULTS
  Among 17,232 cases, 802 incidental durotomies were identified (rate 4.65%). The multivariate odds of durotomy in the oldest patients (age ≥ 73) were 2.4 times greater than the odds of durotomy in the youngest patients (age ≤ 56; P < 0.0001). Durotomy was associated with increased neurological complications and longer hospital stay. Length of stay was a significant driver of cost. The multivariate odds of dural tears in teaching hospitals was significantly higher compared with nonteaching hospitals (odds ratio 1.27; 95% confidence interval, 1.06-1.52; P < 0.005). Durotomy was associated with a $10,885 increase in total hospital charges, and a $3,873 increase in estimated total costs (compared with no durotomy group with P < 0.0001).
  
  
  CONCLUSIONS
  Increasing age is a risk factor for durotomy in primary lumbar fusion. Durotomy is associated with neurological complications, increased length of stay, greater healthcare costs, and is more common in teaching hospitals. Length of stay is an independent driver of cost and complications.
  
  
  METHODS
  3.
authors.affiliation: *Emory University School of Medicine; and †Department of Orthopaedic Surgery, Emory University School of Medicine, Atlanta, GA.
authors.forename: J Stewart
authors.initials: JS
authors.lastname: Buck
authors.forename: S Tim
authors.initials: ST
authors.lastname: Yoon
mesh_terms: D000293:Adolescent; D000328:Adult; D000367:Age Factors; D000368:Aged; D016009:Chi-Square Distribution; D016208:Databases, Factual; D005260:Female; D017722:Hospital Charges; D017721:Hospital Costs; D006801:Humans; D015994:Incidence; D007902:Length of Stay / Q000191:economics; D016015:Logistic Models; D008159:Lumbar Vertebrae / Q000601:surgery*; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D016017:Odds Ratio; D011183:Postoperative Complications / Q000175:diagnosis / Q000191:economics* / Q000453:epidemiology*; D012189:Retrospective Studies; D012307:Risk Factors; D013123:Spinal Fusion / Q000009:adverse effects* / Q000191:economics*; D013130:Spinal Stenosis / Q000175:diagnosis / Q000191:economics* / Q000601:surgery*; D013997:Time Factors; D016896:Treatment Outcome; D014481:United States / Q000453:epidemiology; D055815:Young Adult