SF-36 PCS benefit-cost ratio of lumbar fusion comparison to other surgical interventions: a thought experiment

Abstract

Study design: A retrospective review of prospectively collected data.

Objectives: To review systematically the SF-36 PCS outcomes of a large data set, including several randomized clinical trials for lumbar spine fusion at 1 and 2 years after surgery. We also present for comparison a review of typical changes in SF-36 PCS in other surgical interventions (total knee replacement, total hip replacement, and coronary artery bypass surgery) to define the average reimbursement costs per PCS improvement with each of these interventions.

Summary and background data: Data from 11 prospective multicenter studies (9 Food and Drug Administration Investigational Device Exemption, Randomized Prospective Clinical Trials, class 1 data) accounted for the lumbar spine fusion group (n = 1826). Data for total knee replacement, total hip replacement, and coronary artery bypass surgery were obtained from a comprehensive review of the literature.

Methods: Comparisons of SF-36 PCS improvements were made at defined postoperative time points and with published study findings of other medical conditions. Reimbursement estimates (not including estimated physician and rehabilitation fees) for each surgical intervention were based on Centers for Medicare and Medicaid Services Medicare Provider Analysis and Review and All Payer Data (2002). Cost estimates were calculated for a minimal clinical important improvement (reimbursement dollars/mean PCS change *5.42 point PCS improvement).

Results: SF-36 PCS significantly improved at both 1 and 2 years following lumbar spine fusion surgery (P < 0.0001), and was comparable to the control surgical outcomes. With the use of data from Centers for Medicare and Medicaid Services Medicare Provider Analysis and Review and All Payer Data, hospital reimbursement averaged $15.2-18.2K for lumbar spine fusion, $9.8-11.3K for total knee replacement, $9.6-11.3K for total hip replacement, and $9.8-11.3K for coronary artery bypass surgery. Calculations of reimbursement dollars to elicit minimum clinically important change in PCS of 5.42 points following surgery ranged from $6.1 to $7.3K for lumbar spine fusion, $5.7 to $6.6K for total knee arthroplasty, $3.9 to $4.5K for total hip replacement, and $18.2 to $22.5K for coronary artery bypass surgery.

Conclusion: While the exact numbers may vary for each treatment based on the population studied and the cost estimates used, lumbar fusion cost per benefit achieved was very comparable to other well-accepted medical interventions (total hip replacement, total knee replacement, and coronary artery bypass surgery).