Cost-Effectiveness of Operative vs Nonoperative Treatment of Adult Symptomatic Lumbar Scoliosis an Intent-to-Treat Analysis at Five Year Follow-Up

Leah Y. Carreon MD, MSc; Steven D. Glassman MD; Jon Lurie MD, MS; Christopher I. Shaffrey MD; Michael P. Kelly MD, MSc; Christine R. Baldus RN, MHA; Kelly R. Bratcher RN; Charles H. Crawford III; Elizabeth L. Yanik PhD; Keith H. Bridwell MD


Spine. 2019;44(21):1499-1506. 

In This Article

Abstract and Introduction


Study Design: Secondary analysis using data from the NIH-sponsored study on adult symptomatic lumbar scoliosis (ASLS) that included randomized and observational arms.

Objective: To perform an intent-to-treat cost-effectiveness study comparing operative versus non-operative care for ASLS.

Summary of Background Data: The appropriate treatment approach for ASLS continues to be ill-defined. Nonoperative care has not been shown to improve outcomes. Surgical treatment has been shown to improve outcomes, but is costly with high revision rates.

Methods: Patients with at least five-year follow-up data were included. Data collected every three months included use of nonoperative modalities, medications and employment status. Costs for index and revision surgeries and non-operative modalities were determined using Medicare Allowable rates. Medication costs were determined using the RedBook and indirect costs were calculated based on reported employment status and income. Quality Adjusted Life Years (QALY) was determined using the SF6D.

Results: There were 81 of 95 cases in the Operative (Op) and 81 of 95 in the Non-operative (Non-Op) group with complete five-year follow-up data. Not all patients were eligible for five year follow-up at the time of the analysis. All patients in the Op and 24 (30%) in the NonOp group had surgery by five years. At five years, the cumulative cost for Op was $96,000 with a QALY gain of 2.44 and for Non-Op the cumulative cost was $49,546 with a QALY gain of 0.75 with an Incremental Cost-effectiveness Ratio (ICER) of $27,480 per QALY gain.

Conclusion: In an intent-to-treat analysis, neither treatment was dominant, as the greater gains in QALY in the surgery group come at a greater cost. The ICER for operative compared to non-operative treatment was above the threshold generally considered costeffective in the first three years of the study but improved over time and was highly costeffective at four and five years.

Level of Evidence: 2


There continues to be uncertainty regarding the appropriate treatment approach for patients with Adult Spinal Deformity.[1,2] Similar to patients with lumbar degenerative disorders, patients are initially managed with non-operative treatments such as physical therapy, manipulation, injections and medication. However, there is no firm evidence that these non-operative interventions are effective. A systematic review found only level II evidence for the use of injections and level IV evidence for physical therapy and bracing.[3] Another study showed that non-operative care does not improve a patient's quality of life[4] as measured by the Short Form 12 (SF-12),[5] the Scoliosis Research Society 22R (SRS22R)[6] or the Oswestry Disability Index (ODI).[7,8] While non-operative treatment did not change health status, it is unknown if these patients would have worsened without treatment.[1,4]

Surgical treatment is usually considered when non-operative treatment has failed to improve pain and function. The surgeon, the patient, the patient's caregiver and the payer all contribute to the decision of whether the risk of surgery outweighs the potential benefits. Several studies have shown that surgical treatment improves a patient's quality of life but is costly with high complication[1] and revision rates.[9]

The purpose of this study is to perform cost-effectiveness analysis comparing operative to non-operative treatment using data from subjects enrolled in the National Institutes of Health (NIH) sponsored study on Adult Symptomatic Lumbar Scoliosis (ASLS) using an intent-to-treat analysis.