The Seven-Year Cost-Effectiveness of Anterior Cervical Discectomy and Fusion Versus Cervical Disc Arthroplasty

A Markov Analysis

Jun S. Kim, MD; James Dowdell, MD; Zoe B. Cheung, MD, MS; Varun Arvind, BS; Li Sun, DO; Chanakya Jandhyala, MD; Chierika Ukogu, BS; William Ranson, BS; Samantha Jacobs, BS; Steven McAnany, MD; Samuel Kang-Wook Cho, MD


Spine. 2018;43(22):1543-1551. 

In This Article

Abstract and Introduction


Study Design: Markov model analysis.

Objective: The aim of this study was to determine the 7-year cost-effectiveness of single-level anterior cervical discectomy and fusion (ACDF) versus cervical disc replacement (CDR) for the treatment of cervical disc degeneration.

Summary of Background Data: Both ACDF and CDR are acceptable surgical options for the treatment of symptomatic cervical disc degeneration. Past studies have demonstrated at least equal effectiveness of CDR when compared with ACDF in large randomized Investigational Device Exemption (IDE) studies. Short-term cost-effectiveness analyses at 5 years have suggested that CDR may be the preferred treatment option. However, adjacent segment disease and other postoperative complications may occur after 5 years following surgery.

Methods: A Markov model analysis was used to evaluate data from the LDR Mobi-C IDE study, incorporating five Markov transition states and seven cycles with each cycle set to a length of 1 year. Transition state probabilities were determined from complication rates, as well as index and adjacent segment reoperation rates from the IDE study. Raw SF-12 data were converted to health state utility values using the SF-6D algorithm for 174 CDR patients and 79 ACDF patients.

Results: Assuming an ideal operative candidate who is 40-years-old and failed appropriate conservative care, the 7-year cost was $103,924 for ACDF and $105,637 for CDR. CDR resulted in the generation of 5.33 quality-adjusted life-years (QALYs), while ACDF generated 5.16 QALYs. Both ACDF and CDR were cost-effective, but the incremental cost-effectiveness ratio (ICER) was $10,076/QALY in favor of CDR, which was less than the willingness-to-pay (WTP) threshold of $50,000/QALY.

Conclusion: ACDF and CDR are both cost-effective strategies for the treatment of cervical disc degeneration. However, CDR is the more cost-effective procedure at 7 years following surgery. Further long-term studies are needed to validate the findings of this model.


Anterior cervical discectomy and fusion (ACDF), first implemented in 1957, has been considered the "gold standard" for decades for the treatment of cervical degenerative disc disease after conservative options have been exhausted.[1] For patients presenting with neck and radiating arm pain, motor weakness, and sensory loss due to cervical disc herniation or compressive pathologies, ACDF has been shown to be generally well-tolerated and associated with a high clinical success rate.[2–5] Despite the proven long-term radiographic and clinical success of ACDF, however, literature has shown the procedure to be associated with certain drawbacks, including neurological complications, rapid development of adjacent segment disease, and decreased range of motion owing to solid bony arthrodesis.[6–10]

More recently, cervical disc replacement (CDR) has also become an acceptable surgical option for similar cervical spine pathologies as ACDF. CDR was developed as a motion-sparing alternative to ACDF with purported advantages including minimization of adjacent segment disease and obviation of pseudoarthrosis.[11,12] Five large, multicenter, randomized clinical trials and three meta-analyses have examined the clinical outcomes of ACDF versus CDR and demonstrated at least equal effectiveness of CDR compared with ACDF.[11,13–20] These trials reported on a number of different metrics, including the Neck Disability Index, 36-Item Short Form Health Survey (SF-36), SF-12 Physical Component Summary, neurological improvement, and avoidance of secondary surgical procedures. All five clinical trials reported improvement for all outcomes measured with CDR, although only one trial found a statistically significant improvement with CDR compared with ACDF. With multiple large investigational device exemption (IDE) studies showing the noninferiority of CDR, the cost-effectiveness of this procedure has increasingly become a topic of interest.

Previous cost-effectiveness analysis (CEA) of ACDF and CDR at 5 years after surgery has demonstrated that CDR may be the preferred treatment option.[21] However, as adjacent segment disease and other complications following the surgical treatment of cervical disc disease may occur greater than 5 years following operation, analysis of longer term follow-up data is necessary. The purpose of this study is to determine the 7-year cost-effectiveness of single-level ACDF versus CDR for the treatment of cervical disc degeneration.