title: Perioperative Complications Associated With Posterolateral Spine Fusions: A Study of Elderly Medicare Beneficiaries.
abstract: METHODS
  A retrospective database review.
  
  
  OBJECTIVE
  The aim of this study was to compare the occurrence of complications in patients treated with one to two-level, three to seven-level, and more than eight level fusions.
  
  
  BACKGROUND
  Elderly patients constitute a rapidly growing demographic with an increasing need for spinal procedures. Complication rates for spinal surgery in elderly patients range from 37% to 80% with major complications occurring in 12% to 21% of patients.
  
  
  METHODS
  The PearlDiver database (2005-2012) was utilized to compare perioperative complication rates in patients aged 65 years and older undergoing posterolateral fusion of one to two (n = 90,527); three to seven (n = 23,827), and more than eight (n = 2758) thoracolumbar levels. Cohorts were matched by demographics and comorbidities. Ninety-day medical and surgical complication and mortality rates were determined.
  
  
  RESULTS
  In the full, unmatched cohort, the major complication rate was 15.9%, with matched cohorts of one to two, three to seven, and eight-level fusions associated with major complication rates of 12.5%, 20.5%, and 35.4%, respectively. Patients treated with 8+ level fusions had 3.8 and 2.1 times greater odds of developing a major complication than patients treated with 1 to 2 and 3 to 7-level fusions, respectively (P < 0.0001). Patients treated with more than eight-level fusions had 3.9 and 10.8 times increased odds of experiencing mortality than those treated with three to seven-level and one to two-level fusions, respectively.
  
  
  CONCLUSIONS
  Elderly patients treated with spine fusions spanning more than eight levels experience significantly increased complication rates when compared with patients treated with fusions of shorter length.
  
  
  METHODS
  3.
authors.affiliation: Department of Orthopaedic Surgery, Johns Hopkins University, Baltimore, MD.
authors.forename: Varun
authors.initials: V
authors.lastname: Puvanesarajah
authors.affiliation: Department of Orthopaedic Surgery, University of Virginia, Charlottesville, VA.
authors.forename: Jourdan M
authors.initials: JM
authors.lastname: Cancienne
authors.affiliation: Department of Orthopaedic Surgery, University of Virginia, Charlottesville, VA.
authors.forename: Brian C
authors.initials: BC
authors.lastname: Werner
authors.affiliation: Department of Orthopaedic Surgery, Johns Hopkins University, Baltimore, MD.
authors.forename: Amit
authors.initials: A
authors.lastname: Jain
authors.affiliation: Department of Orthopaedic Surgery, University of Virginia, Charlottesville, VA.
authors.forename: Anuj
authors.initials: A
authors.lastname: Singla
authors.affiliation: Department of Orthopaedic Surgery, University of Virginia, Charlottesville, VA.
authors.forename: Adam L
authors.initials: AL
authors.lastname: Shimer
authors.affiliation: Department of Orthopaedic Surgery, University of Virginia, Charlottesville, VA.
authors.forename: Francis H
authors.initials: FH
authors.lastname: Shen
authors.affiliation: Department of Orthopaedic Surgery, University of Virginia, Charlottesville, VA.
authors.forename: Hamid
authors.initials: H
authors.lastname: Hassanzadeh
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D015331:Cohort Studies; D016208:Databases, Factual; D005260:Female; D006801:Humans; D007431:Intraoperative Complications / Q000209:etiology*; D008297:Male; D006278:Medicare; D011183:Postoperative Complications / Q000209:etiology*; D012189:Retrospective Studies; D013123:Spinal Fusion / Q000009:adverse effects* / Q000379:methods; D014481:United States