PMD42 Cost-Effectiveness of Coflex® Interlaminar Stabilization Compared with Instrumented Posterior Spinal Fusion for Spinal Stenosis and Spondylolisthesis

Abstract

BACKGROUND CONTEXT: In recent years, surgicalmanagement of vertebral compression fractures (VCFs) has become controversial, due largely to inconsistent outcomes reported from vertebroplasty randomized trials. PURPOSE: To characterize the cost to Medicare for treating VCF diagnosed patients by nonsurgical management, vertebroplasty (VP), or balloon kyphoplasty (BKP). We hypothesized that surgical treatments for VCFs using VP or BKP would be a cost-effective alternative to nonsurgical management for the Medicare patient population. STUDY DESIGN/SETTING: The study utilized the 100% and 5% U.S. Medicare national claims data from 2005-2008. PATIENT SAMPLE: BKP and VP patients were identified using ICD-9CM and CPT-4 codes. Life expectancy was based on a cohort of 858,978 VCF patients in the 100% Medicare data, while payer costs were based on 67,018 VCF patients in the 5% Medicare data. OUTCOME MEASURES: Cost per life year gained (LYG). METHODS: Cost per LYG for VCF patients was compared between operated (BKP and VP) and non-operated patients and between BKP and VP patients, all as a function of age and gender. Life expectancy was estimated using a parametric Weibull survival model (adjusted for comorbidities). Median payer costs were identified for each treatment group for up to 3 years following VCF diagnosis. A discount rate of 3% was used for the base case in the cost-effectiveness analysis, with 0% and 5% discount rates used in sensitivity analyses. RESULTS: After accounting for the differences in median costs and using a discount rate of 3%, the cost per LYG for BKP and VP patients ranged from $1,863 to $6,687 and from $2,452 to $13,543, respectively, compared with non-operated patients. The cost per LYG for BKP compared with VP ranged from -$4,878 to $2,763. CONCLUSIONS: Among patients for whom surgical treatment was indicated, BKP was found to be cost-effective, and perhaps even cost saving, compared to VP. Both interventions would be considered cost-effective in terms of cost per LYG. FDA DEVICE/DRUG STATUS: Vertebroplasty (Approved for this indication), Kyphoplasty (Approved for this indication).