title: Cost-utility analysis of minimally invasive versus open multilevel hemilaminectomy for lumbar stenosis.
abstract: METHODS
  Two-year cost-utility study comparing minimally invasive (MIS) versus open multilevel hemilaminectomy in patients with degenerative lumbar spinal stenosis.
  
  
  OBJECTIVE
  The objective of the study was to determine whether MIS versus open multilevel hemilaminectomy for degenerative lumbar spinal stenosis is a cost-effective advancement in lumbar decompression surgery.
  
  
  BACKGROUND
  MIS-multilevel hemilaminectomy for degenerative lumbar spinal stenosis allows for effective treatment of back and leg pain while theoretically minimizing blood loss, tissue injury, and postoperative recovery. No studies have evaluated comprehensive healthcare costs associated with multilevel hemilaminectomy procedures, nor assessed cost-effectiveness of MIS versus open multilevel hemilaminectomy.
  
  
  METHODS
  Fifty-four consecutive patients with lumbar stenosis undergoing multilevel hemilaminectomy through an MIS paramedian tubular approach (n=27) versus midline open approach (n=27) were included. Total back-related medical resource utilization, missed work, and health state values [quality adjusted life years (QALYs), calculated from EuroQuol-5D with US valuation] were assessed after 2-year follow-up. Two-year resource use was multiplied by unit costs based on Medicare national allowable payment amounts (direct cost) and work-day losses were multiplied by the self-reported gross-of-tax wage rate (indirect cost). Difference in mean total cost per QALY gained for MIS versus open hemilaminectomy was assessed as incremental cost-effectiveness ratio (ICER: COST(MIS)-COST(OPEN)/QALY(MIS)-QALY(OPEN)).
  
  
  RESULTS
  MIS versus open cohorts were similar at baseline. MIS and open hemilaminectomy were associated with an equivalent cumulative gain of 0.72 QALYs 2 years after surgery. Mean direct medical costs, indirect societal costs, and total 2-year cost ($23,109 vs. $25,420; P=0.21) were similar between MIS and open hemilaminectomy. MIS versus open approach was associated with similar total costs and utility, making it a cost equivalent technology compared with the traditional open approach.
  
  
  CONCLUSIONS
  MIS versus open multilevel hemilaminectomy was associated with similar cost over 2 years while providing equivalent improvement in QALYs. In our experience, MIS versus open multilevel hemilaminectomy is a cost equivalent technology for patients with lumbar stenosis-associated radicular pain.
authors.affiliation: Department of Neurosurgery, Vanderbilt University Medical Center, Nashville, TN, USA.
authors.forename: Scott L
authors.initials: SL
authors.lastname: Parker
authors.forename: Owoicho
authors.initials: O
authors.lastname: Adogwa
authors.forename: Brandon J
authors.initials: BJ
authors.lastname: Davis
authors.forename: Erin
authors.initials: E
authors.lastname: Fulchiero
authors.forename: Oran
authors.initials: O
authors.lastname: Aaronson
authors.forename: Joseph
authors.initials: J
authors.lastname: Cheng
authors.forename: Clinton J
authors.initials: CJ
authors.lastname: Devin
authors.forename: Matthew J
authors.initials: MJ
authors.lastname: McGirt
mesh_terms: D003362:Cost-Benefit Analysis; D005260:Female; D017048:Health Care Costs / Q000706:statistics & numerical data*; D006801:Humans; D007796:Laminectomy / Q000191:economics* / Q000706:statistics & numerical data; D008159:Lumbar Vertebrae / Q000601:surgery*; D008297:Male; D008875:Middle Aged; D019060:Minimally Invasive Surgical Procedures / Q000191:economics* / Q000706:statistics & numerical data; D015995:Prevalence; D012307:Risk Factors; D013130:Spinal Stenosis / Q000191:economics* / Q000453:epidemiology*; D013714:Tennessee / Q000453:epidemiology; D016896:Treatment Outcome