Does a Combined Anterior-Posterior Elective Lumbar Fusion Provide More Value than Posterior Only? An Application of the Operative Value Index

Introduction: Lumbar fusion is a common treatment for spinal conditions such as stenosis and deformity. While both anterior-posterior (AP) and posterior-only approaches are used, their cost-effectiveness remains uncertain. This study aims to compare the costs and value of AP and posterior-only lumbar fusions using time-driven activity-based costing (TDABC) and patient-reported outcomes.

Methods: A retrospective review of patients undergoing AP or posterior lumbar fusion from 2017 to 2022 was conducted. TDABC was used to assign intraoperative costs based on resource utilization, and the Oswestry Disability Index (ODI) was collected preoperatively and 3-months postoperatively. The Operative Value Index (OVI) was defined as the percent improvement in ODI per $1000 spent. Kruskal-Wallis analysis and multivariable regression compared costs, operative times, and OVI.

Results: Among 133 analyzed patients, 41 underwent AP fusion and 92 underwent posterior-only fusion. The average cost of AP fusion ($22,964) was significantly higher than posterior-only fusion ($11,112), driven by greater supply and personnel costs (p < 0.001). AP procedures also had longer operative times but showed no significant difference in ODI improvement (p=0.682). Posterior-only fusions demonstrated a significantly higher OVI (p < 0.05).

Conclusion : Both AP and posterior-only fusion provide comparable functional improvements, but AP is associated with higher costs. Posterior-only fusions may be preferable in value-based care models for their cost-effectiveness. Further research is needed to assess long-term outcomes.