There is no "Value Penalty" for revision spine surgery: an application of the operative value index for primary versus revision lumbar fusions

The increasing prevalence of elective lumbar fusions has been accompanied by a steady rise in revision procedures. Few studies have identified the relative cost-effectiveness of revision lumbar fusion using detailed costing methodology. Here, we aim to compare the "value" (outcomes achieved per dollar spent) of primary versus revision lumbar fusion by integrating time-driven activity-based costing (TDABC) with patient-reported outcomes (PROs). 292 patients were prospectively enrolled to undergo elective lumbar fusion. Revision surgery was defined as any case of lumbar fusion after a previous lumbar spine surgery. TDABC was employed to identify intraoperative costs for all cases. Oswestry Disability Index (ODI) scores were collected both preoperatively and at 6-months postoperatively. "Value" was measured through the Operative Value Index (OVI), defined as the percent improvement in ODI per $1,000 spent intraoperatively. Multivariable linear regression, accounting for confounders, was performed to assess whether revision surgery was significantly associated with total cost and OVI. Secondary analyses were performed to compare costs and OVI between primary fusions, revisions for prior decompression and fusion, and revisions for prior decompression alone. The average total cost of a revision fusion was $18,252 +/- $8,496, compared to $18,073 +/- $8,894 for a primary fusion. The average OVI for these groups were 1.79 and 1.65, respectively. On multivariable regression analysis, there were no significant differences in OVI (p = 0.423) or total cost (p = 0.841) between primary and revision cohorts.In the era of value-based care, it is increasingly important for hospitals to identify drivers of variation in the cost-effectiveness of neurosurgical care. By integrating PROs with detailed cost data, we demonstrate that revision lumbar fusions may not significantly differ in cost or value compared to primary fusions.