Letter Posted: Medical Policy Number 0016 “Back Pain—Invasive Procedures”


Via email:
SUBJECT: Medical Policy Number 0016 “Back Pain—Invasive Procedures”

Dear Mr. Kane and Drs. Moffitt and McDonough,

On behalf of the American Association of Neurological Surgeons (AANS), Congress of Neurological Surgeons (CNS) and the AANS/CNS Joint Section on Disorders of the Spine and Peripheral Nerves (DSPN), we write to express our grave concerns regarding Aetna’s coverage policy for CPT code 22853, which governs the use of spine cages in anterior cervical diskectomy and fusion (ACDF) surgery.

While every other commercial payer empowers surgeons and their patients to decide what implants are best suited for their cervical fusion surgery, Aetna remains the sole major commercial insurer that does precisely the opposite. The current Aetna coverage determination policy deprives patients and their surgeons of the ability to choose from various cervical interbody graft options that are either equivalent to or have superior surgical outcomes. After a comprehensive review of the current literature, it has become apparent to the AANS, CNS and DSPN that there is an immediate need for Aetna to reexamine and update its coverage determination policy that currently precludes the use of interbody cages in ACDF cases.

The offending policy is in Section H (Intervertebral body fusion devices), paragraph 2 of Aetna’s Medical Policy Number 0016, “Back Pain—Invasive Procedures,” which delineates the exclusion of spine cage usage for routine cervical fusion, and states “[s]pine cages are otherwise not considered medically necessary for cervical fusion because they have not been proven more effective than bone graft for this indication” (Emphasis added). Aetna remains the lone major commercial payer that limits polymer or metallic interbody spacers to neoplastic, adjacent segment levels or trauma cases requiring corpectomy, which represent the vast minority of circumstances. A blanket denial of the 22853 in routine ACDFs detrimentally impacts 85-90% of anterior cervical cases.
The AANS, CNS and DSPN strongly contend that this policy unduly confines patient options, particularly in the light of innovations in cage design, material science and biomechanical understanding.

  1. Spine cages from earlier generations, utilizing materials like poly-ether-ether-ketone (PEEK) or titanium, have demonstrated comparable outcomes to structural allografts when used in ACDF cases.1 In recent years, significant advancements have been achieved in the field of material science regarding cervical cage design. A prime example of this progress is the emergence of 3D-printed porous titanium cages. These porous titanium cages not only expedite bone conduction but also promote osteogenesis by stimulating bone formation and expediting bone integration, thereby enhancing the likelihood of successful implantation. The textured, roughened surface texture of the porous titanium cages encourages bone cells to integrate with and envelop the cage, facilitating fusion.2,3
    Additionally, the ability to tailor porous titanium cages to conform to vertebral endplate curvature diminishes the risk of subsidence. Furthermore, these cages can be optimized to align with the available vertebral endplate dimensions after cervical diskectomy. The research underscores that an increased implant-to-bone ratio within the anterior cervical spine interbody spaces substantially diminishes the likelihood of implant subsidence.4,5 The assortment of choices, spanning large to standard sizes of the customized spine cages, empowers surgeons to select an appropriate match for the patient’s anatomy, which ensures optimal coverage of bony endplates, thereby minimizing subsidence while fostering osseointegration. Moreover, porous titanium cages have modulus of elasticity that is closer to the cortical bone, further decreasing its risk of subsidence.6
    Biomechanical analyses confirmed that porous titanium cages mitigate the risk of subsidence and enhance stability by incorporating bone, leading to enhanced fusion outcomes.7 Recent clinical studies have also confirmed the benefit of 3D-printed titanium cages. A study by Singh et al. compared 3D-printed titanium cages and allografts in ACDF patients, revealing that the 3D titanium cage exhibited significantly lower subsidence rates and maintained superior segmental lordosis compared to allograft cages.8
  2. The employment of allografts carries inherent risks, including the potential transmission of life-threatening pathogens such as Creutzfeldt-Jakob disease. McVeigh et al. published a recent report of six patients infected with tuberculosis transmitted from cadaveric bone grafts.9 Moreover, processed cadaveric bone tends to be brittle, increasing the likelihood of fractures during insertion, particularly in cases of compressed disc spaces. Additionally, patients might harbor reservations about incorporating cadaveric bone into their bodies based on religious or cultural beliefs (e.g., Jehovah’s Witness, Asian and Native American patients, respectively).

The ongoing denial of spine cage usage in ACDF cases has elicited substantial concerns within the neurosurgical community. For example, we are including the letter from a leading expert and past chair of the DSPN, Richard G. Fessler, MD, PhD, for Aetna’s review. Dr. Fessler’s letter to Aetna’s former CEO best captures the sentiment of all the DSPN members regarding this issue.

Finally, it is impossible to reconcile Aetna’s current coverage determination policy with the recently published literature alongside the coverage determination policies of other major commercial payers, including, for example, United Healthcare, Cigna and Humana. These payers rightly recognize ACDF with a polymer or metallic interbody spacer as scientifically sound and medically necessary. At the same time, out of the blue, Aetna determines that the spacer is now experimental and not medically necessary. As the literature continues to mount, demonstrating equivalency, if not superiority, Aetna’s position becomes increasingly tenuous and unsupported by current scientific literature review standards. In our view, Aetna is prioritizing costs over patient safety rather than following the evidence as these other payers are doing. Aetna’s lone position on the 22853 among all commercial payers has no other plausible explanation.

On behalf of the AANS, CNS, DSPN and the patients we serve, we strongly urge Aetna to modify its restrictive coverage determination policy, which adversely affects patient well-being and inappropriately interferes with surgeon-patient autonomy in selecting treatment options. Technological progress highlights the advantages of incorporating cervical cages into anterior cervical fusion procedures, offering an equivalent, if not superior, alternative to cadaveric bone.

We welcome an updated and scientifically sound coverage determination policy from Aetna that empowers the surgeon and the patient to mutually decide on one of the most consequential decisions our patients have to make: what implant to use in their own bodies. Until then, our spine surgeons will continue to educate their patients about the differences between Aetna’s anachronistic and discordant coverage policy and the scientifically sound coverage policies provided by other leading insurance companies. Furthermore, we will provide our patients with literature about the cervical spacer options that should be accessible to anyone undergoing a cervical fusion procedure.
Thank you for considering our views and request. We welcome the opportunity to meet with you to discuss our concerns with this policy further.

Anthony L. Asher, MD, President
American Association of Neurological Surgeons

Elad I. Levy, MD, President
Congress of Neurological Surgeons

Eric Potts, MD, Chair
AANS/CNS Joint Section on Disorders of the
Spine and Peripheral Nerves

Yi Lu, MD PhD, Chair
DSPN Payor Response Committee


  1. Wang M, Chou D, Chang CC, Hirpara A, Liu Y, Chan AK, Pennicooke B, Mummaneni PV. Anterior cervical discectomy and fusion performed using structural allograft or polyetheretherketone: pseudarthrosis and revision surgery rates with minimum 2-year follow-up. J Neurosurg Spine. 2019 Dec 13:1-8. doi: 10.3171/2019.9.SPINE19879. Epub ahead of print. PMID: 31835252.
  2. Wang R, Ni S, Ma L, Li M. Porous construction and surface modification of titanium-based materials for osteogenesis: A review. Front Bioeng Biotechnol. 2022 Aug 25;10:973297. doi: 10.3389/fbioe.2022.973297. PMID: 36091459; PMCID: PMC9452912.
  3. Muthiah N, Yolcu YU, Alan N, Agarwal N, Hamilton DK, Ozpinar A. Evolution of polyetheretherketone (PEEK) and titanium interbody devices for spinal procedures: a comprehensive review of the literature. Eur Spine J. 2022 Oct;31(10):2547-2556. doi: 10.1007/s00586-022-07272-1. Epub 2022 Jun 10. PMID: 35689111.
  4. Moussa A, Tanzer M, Pasini D. Cervical fusion cage computationally optimized with porous architected Titanium for minimized subsidence. J Mech Behav Biomed Mater. 2018 Sep;85:134-151. doi: 10.1016/j.jmbbm.2018.05.040. Epub 2018 Jun 2. PMID: 29890380.
  5. Godlewski B, Bebenek A, Dominiak M, Karpinski G, Cieslik P, Pawelczyk T. Subsidence following cervical discectomy and implant-to-bone ratio. BMC Musculoskelet Disord. 2022 Aug 4;23(1):750. doi: 10.1186/s12891-022-05698-8. PMID: 35927645; PMCID: PMC9351094.
  6. Wang R, Ni S, Ma L, Li M. Porous construction and surface modification of titanium-based materials for osteogenesis: A review. Front Bioeng Biotechnol. 2022 Aug 25;10:973297. doi: 10.3389/fbioe.2022.973297. PMID: 36091459; PMCID: PMC9452912.
  7. Fogel G, Martin N, Williams GM, Unger J, Yee-Yanagishita C, Pelletier M, Walsh W, Peng Y, Jekir M. Choice of Spinal Interbody Fusion Cage Material and Design Influences Subsidence and Osseointegration Performance. World Neurosurg. 2022 Jun;162:e626-e634. doi: 10.1016/j.wneu.2022.03.087. Epub 2022 Mar 26. PMID: 35346883.
  8. Singh H, Kukowski NR, Lunati MP, Dawes A, Kim CH, Kim S, Rhee JM. Porous 3D Printed Titanium Cages in Anterior Cervical Discectomy and Fusion are Associated With Less Subsidence, Improved Maintenance of Segmental Lordotic Correction, and Similar Clinical Outcomes as Allograft. Global Spine J. 2022 Sep 3:21925682221124527. doi: 10.1177/21925682221124527. Epub ahead of print. PMID: 36062347.
  9. McVeigh LG, Zaazoue MA, Lane BC, Voorhies JM, Bradbury J. Management and outcomes of surgical site tuberculosis infection due to infected bone graft in spine surgery: a single-institution experience and 1-year postoperative follow-up. J Neurosurg Spine. 2022 Oct 21;38(2):281-292. doi: 10.3171/2022.7.SPINE22534. PMID: 36272124.


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