title: A Cost-Effectiveness Comparison Between Open Transforaminal and Minimally Invasive Lateral Lumbar Interbody Fusions Using the Incremental Cost-Effectiveness Ratio at 2-Year Follow-up.
abstract: BACKGROUND
  Direct cost comparisons between minimally invasive spine surgeries and the open options are rare.
  
  
  OBJECTIVE
  To compare healthcare costs associated with open transforaminal lumbar interbody fusion (TLIF) and minimally invasive lateral lumbar interbody fusion (LLIF) by calculating the incremental cost-effectiveness ratio (ICER) and to calculate the thresholds for minimum clinically important difference and minimum cost-effective difference for patient-reported outcome measures at the 2-year follow-up.
  
  
  METHODS
  Forty-five patients who underwent single-level TLIF and 29 patients who underwent single-level stand-alone LLIF were included in the comparison. All costs from diagnosis through the 2-year follow-up were available from a comprehensive single-center data bank within a unified hospital system. Payment provided for all spine-related medical resource use from the time of diagnosis through 2 years was recorded. A 0% discount rate was applied. Quality-adjusted life-years (QALYs) were calculated from the EuroQol-5D collected in an unbiased manner. Difference in total cost per QALY gained for LLIF minus that for TLIF was assessed as the estimate of the ICER from a US perspective.
  
  
  RESULTS
  Significant improvements were observed at the 2-year follow-up for both TLIF and LLIF with the Short Form-36 physical component summary, Oswestry Disability Index, visual analog scale back pain and leg pain scores, and EuroQol-5D. ICER calculations revealed similar mean cumulative QALYs gained at the 2-year interval (0.67 for TLIF and 0.60 for LLIF; P = .33). Median total costs of care after TLIF and LLIF were $44 068 and $45 574, respectively (P = .96). Minimum cost-effective difference thresholds with an anchor of <$50 000 per QALY were higher than minimum clinically important difference thresholds for all patient-reported outcome measures. Total mean cost and EuroQol-5D were statistically equivalent between the 2 treatment groups.
  
  
  CONCLUSIONS
  TLIF and LLIF produced equivalent 2-year patient outcomes at an equivalent cost-effectiveness profile.
authors.affiliation: Department of Neurological Surgery, University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania.
authors.forename: Gurpreet S
authors.initials: GS
authors.lastname: Gandhoke
authors.forename: Han Moe
authors.initials: HM
authors.lastname: Shin
authors.forename: Yue-Fang
authors.initials: YF
authors.lastname: Chang
authors.forename: Zachary
authors.initials: Z
authors.lastname: Tempel
authors.forename: Peter C
authors.initials: PC
authors.lastname: Gerszten
authors.forename: David O
authors.initials: DO
authors.lastname: Okonkwo
authors.forename: Adam S
authors.initials: AS
authors.lastname: Kanter
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001416:Back Pain / Q000453:epidemiology / Q000601:surgery; D003362:Cost-Benefit Analysis; D004185:Disability Evaluation; D005260:Female; D005500:Follow-Up Studies; D017048:Health Care Costs; D006801:Humans; D008159:Lumbar Vertebrae / Q000601:surgery*; D008297:Male; D008875:Middle Aged; D019060:Minimally Invasive Surgical Procedures / Q000191:economics* / Q000379:methods*; D019635:Neurosurgical Procedures / Q000191:economics* / Q000379:methods*; D010147:Pain Measurement; D011788:Quality of Life; D019057:Quality-Adjusted Life Years; D013123:Spinal Fusion / Q000191:economics* / Q000379:methods*; D016896:Treatment Outcome