A Cost-Driver Analysis of Transforaminal Lumbar Interbody Fusions: A 10-Year Single-Center Analysis.

STUDY

DESIGN

Retrospective cohort.

OBJECTIVE

To analyze costs (reimbursements herein "cost") of transforaminal lumbar interbody fusions (TLIF) over a 10-year period at a single academic center.

SUMMARY OF BACKGROUND DATA: Lumbar fusions are responsible for some of the highest charges billed to payers.

METHODS

Three hundred seventy-six patients who underwent single-level TLIF between 2014 and 2024 were reviewed. Costs were obtained from the Value Driven Outcomes framework and stratified by category, including implants. Multivariable fixed-effects regression was used to identify independent predictors of total and implant costs, controlling for patient and procedural factors.

RESULTS

Implants accounted for the largest share of total TLIF cost, comprising 51% on average. Within implant costs, bone graft expenses were stable over time, with implant hardware accounting for most of the variability in cost. Expandable cages were associated with a 25% higher total cost (P=0.023) and a 42% higher implant cost (P=0.031) compared with static cages.

CONCLUSIONS

The primary driver of total cost for single-level TLIF was implant type, with expandable cages costing significantly more than static. Given this finding, the choice of implant may be a viable target for price reduction and optimizing value. Further studies are warranted to determine the impact of cage type on other outcomes.

LEVEL OF EVIDENCE: Level III.