Can We Finally Quantify Value for Lumbar Fusions? Introducing the Operative Value Index (OVI)

This is a retrospective analysis of 142 consecutive single-level transforaminal lumbar interbody fusions (TLIFs) performed by neurosurgeons at a large academic center.

To integrate patient-reported outcomes (PROs) with time-driven activity-based costing (TDABC) to quantify value at the surgeon-level and procedure-level.

PRO and cost analyses have become mainstays of clinical research for spine surgery in recent years. To our knowledge, however, few attempts have been made to merge PROs with TDABC to quantify the value of surgical care.

Intraoperative TDABC was used to estimate both direct and indirect costs. Individual costs were obtained by direct observation, electronic medical records, and through querying multiple departments (business operations, sterile processing, plant operations, and pharmacy). Oswestry Disability Index (ODI) scores were collected at baseline and 3-months after surgery. The operative value index (OVI) was defined as the percent improvement in ODI per $1000 spent intraoperatively. We also divided the total intraoperative cost by the absolute ODI point-change for each case to calculate a unit price for outcomes (UPO). Generalized linear mixed models (GLMM) were built to assess surgeon-level variability in OVI. Three distinct surgeon cohorts were created: surgeon A (n=75 cases), surgeon B (n=39 cases), and "other surgeons" (n=7 surgeons and 28 cases).

One hundred forty-two single-level TLIFs were performed by 9 surgeons from 2017 to 2022. The average total cost of a one-level TLIF was $11,984±$3312. The average OVI and UPO for all cases was 3.2±4.3 and $643±$3929, respectively. On GLMM, "other surgeons" were associated with significantly decreased OVI (P<0.05) compared with Surgeon A, though there was no significant difference in OVI between Surgeon A and Surgeon B (P=0.56).

We present novel metrics that quantify value for single-level TLIF by combining a diagnosis-specific PRO with TDABC. Metrics such as these can help stakeholders identify drivers of variation in the value provided by spine surgeons.