Are you a Candidate for Cervical Disc Replacement?
Clinical Perspectives · Cervical Spine · Naples FL
Are you a candidate for
cervical disc replacement?
The short answer is: possibly — and age is not what determines it. I have done cervical disc replacements on patients in their 20s and on patients in their 70s. The question is never how old you are. The question is what your anatomy shows.
Why most patients are only offered fusion —
and what they are not told
When a patient with cervical disc disease reaches the surgical threshold, the operation they are most often offered is ACDF — anterior cervical discectomy and fusion. ACDF is a well-established procedure with a long track record and good outcomes. For certain anatomical situations it is the right operation. But for a meaningful subset of patients — one or two-level cervical disc disease without instability, without severe facet arthritis, with adequate disc height — there is a motion-preserving alternative with superior long-term data that most patients are never told about.
Anterior cervical disc arthroplasty (ACDA) removes the same compressive disc tissue and decompresses the same nerve root or spinal cord. The approach is identical. What differs is what happens at that level afterward. ACDF fuses the segment permanently. ACDA replaces the disc with a prosthetic implant that preserves motion. At ten years of follow-up, the data clearly favors disc replacement for the right anatomy.
Why some surgeons don’t offer it —
and why that matters for your decision
There are several reasons a spine surgeon may not offer cervical disc replacement, and understanding them helps you evaluate the recommendation you have received.
They have not been trained to do it. Implanting a cervical disc prosthesis — Simplify® or ProDisc-C®, the devices certified and used here — requires specific device certification beyond standard spine surgery training. Most cervical spine surgeons in the United States, including excellent surgeons at major academic centers, have not pursued this certification. A surgeon who is not certified cannot offer the operation. That is not malpractice — it is a structural feature of a healthcare system where not every surgeon pursues every available credentialing pathway. The consequence for patients is that a significant proportion of disc replacement candidates are fused without ever knowing the alternative existed.
They do not believe in it. Some surgeons are genuinely skeptical of disc replacement and prefer fusion for all their patients. That position is worth engaging with. Ask what the basis of the skepticism is — whether it is a concern about the evidence, about long-term device durability, or about a specific technical concern in your case. A blanket dismissal without engagement with the IDE trial and ten-year RCT data is a different matter than a specific anatomical argument.
Fusion is simpler and more standardized. ACDF is one of the most commonly performed spine procedures in the United States. It is well within the routine of any trained cervical spine surgeon. Disc replacement through the same anterior approach adds a layer of technical precision — proper prosthetic sizing, endplate preparation, range-of-motion assessment intraoperatively — that requires additional training and comfort with the implant system. For a surgeon who does both, this is minor. For a surgeon who predominantly performs ACDF, it may simply not be part of their practice.
What the ten-year data shows —
fewer secondary surgeries, less adjacent segment disease
A 2023 systematic review with meta-analysis published in Spine by Quinto et al. examined 10-year outcomes of cervical disc arthroplasty versus ACDF across randomized controlled trials and comparative cohort studies. CDA showed significantly fewer secondary surgeries and significantly fewer adverse events compared to ACDF at 10-year follow-up (p<0.05). Neurological success was equivalent. NDI and VAS scores statistically favored CDA, though the absolute differences did not reach minimal clinically important differences — meaning both operations produce good outcomes, and the long-term practical advantage of disc replacement is primarily in avoiding subsequent surgery.
Quinto ES, et al. Ten-year outcomes of cervical disc arthroplasty versus anterior cervical discectomy and fusion: a systematic review with meta-analysis. Spine. 2024;49(7):463–469. doi:10.1097/BRS.0000000000004887
The mechanism is adjacent segment disease (ASD) — the accelerated degeneration that occurs at the levels immediately above and below a fused segment. When motion is eliminated at one level, the mechanical load that level would have absorbed is redistributed to the adjacent levels. Over years, this added stress accelerates wear at those levels, producing stenosis, disc degeneration, and eventually symptoms that require additional surgery. Disc replacement preserves motion and prevents this redistribution.
A meta-analysis by Hu et al. (2016, PLoS One) pooled data from 8 prospective randomized controlled trials including 1,317 CDA and 1,051 ACDF patients with minimum 4-year follow-up. CDA produced significantly less superior adjacent segment degeneration, alongside significantly higher overall success, NDI success, and neurological success rates, and significantly lower rates of secondary procedures and implant-related serious adverse events. NDI, VAS neck pain, VAS arm pain, and SF-36 physical component scores all favored CDA with statistical significance.
Hu Y, et al. Mid- to long-term outcomes of cervical disc arthroplasty versus ACDF: a systematic review and meta-analysis of eight prospective randomized controlled trials. PLoS One. 2016;11(2):e0149312. doi:10.1371/journal.pone.0149312
There is no age cutoff —
the question is anatomy, not birthdate
Patients routinely assume there is a maximum age for disc replacement — that past 60, or 65, or some threshold they cannot name, fusion becomes the only option. That assumption is wrong.
I have performed cervical disc replacements on patients in their 20s. I have performed them on patients in their 70s. Age does not determine candidacy. Anatomy does.
What does increase with age is the probability of findings that independently preclude disc replacement: facet arthritis progresses over time, instability may develop, disc height may decrease. These findings are assessed directly on imaging. They are not inferred from age. A patient who is 74 with preserved facet joints, adequate disc height, and stable alignment on flexion-extension films is assessed the same way as a patient who is 34 with the same anatomy. The operation either fits the anatomy or it does not.
What makes someone a candidate —
and what rules it out
Anatomy that supports disc replacement — what we look for
One or two-level cervical disc diseaseThe strongest evidence base for ACDA is at one or two levels. The FDA-approved indications for Simplify® and ProDisc-C® cover one and two-level cervical disc replacement. Three or more levels shifts the mechanical and risk-benefit calculation; most three-level cases are better addressed with fusion or a hybrid approach combining disc replacement at one or two levels with fusion at another.
No significant segmental instabilityACDA preserves motion at the operated segment. A segment with excessive translational motion on flexion-extension X-rays requires stabilisation, not motion preservation. Dynamic instability — greater than approximately 3–3.5 mm of translation at the operative level — is a contraindication to disc replacement and an indication for fusion.
Normal or near-normal facet joints at the operative levelThe prosthetic disc preserves motion at the segment, which means the facet joints at that level continue to flex, extend, and rotate. Pre-existing severe facet arthritis at the operative level means those joints cannot accommodate the preserved motion comfortably, potentially producing persistent facet-mediated pain despite a successful decompression. The facets must be healthy enough to tolerate restored motion.
Adequate disc heightThe prosthetic disc must have a disc space of sufficient height to seat correctly and function mechanically. Moderate disc height reduction is generally manageable with appropriate implant sizing. Severe disc collapse — where the endplates are nearly approximated — limits the available space for proper prosthetic seating.
Predominantly soft or moderate disc herniation or spondylosisACDA works best when the compression arises primarily from the disc or moderate osteophytes. Significant OPLL changes the calculus considerably — extensive ossification may necessitate a posterior laminectomy and fusion rather than an anterior approach at all, making disc replacement versus ACDF a secondary question.
Adequate bone qualityThe prosthetic disc anchors into the vertebral endplates. Severe osteoporosis can compromise secure seating and long-term stability of the implant. Bone quality is assessed as part of the preoperative work-up when there is clinical reason to do so.
When ACDF is the right operation — not a consolation prize
ACDF is not the inferior operation for patients who do not qualify for disc replacement. It is the correct operation for specific anatomical situations, and it produces excellent outcomes in those patients. The right question is never which operation is better in the abstract — it is which operation is right for this anatomy.
Significant segmental instability or spondylolisthesisWhen flexion-extension X-rays show excessive translation at the operative level, fusion stabilises the instability that disc replacement cannot. Instability is an indication for ACDF, not ACDA.
Severe facet arthritis at the operative levelWhen the facet joints at the level to be treated are severely arthritic, preserving motion through those joints may perpetuate or worsen facet-mediated neck pain. Fusion eliminates motion at that level and removes the arthritic facets from the pain equation.
Three or more levels requiring surgeryLong-segment disc replacement at three or more levels is outside the current evidence base and FDA-approved indications. Most three-level or greater cervical disease is addressed with fusion, or a hybrid approach combining disc replacement at one or two levels with fusion at the remaining levels.
Significant OPLLOssification of the posterior longitudinal ligament often changes the operative approach entirely. Moderate OPLL may be managed anteriorly with ACDF. More extensive OPLL — particularly when it spans multiple levels or causes significant canal compromise — frequently necessitates a posterior approach: laminectomy with fusion, or laminoplasty, to decompress the cord without directly manipulating a calcified, adherent ligament from the front. In these cases the question is not disc replacement versus ACDF; it is whether the anterior approach is appropriate at all.
Severe myelopathy requiring combined anterior-posterior decompressionMyelopathy by itself is not a contraindication to disc replacement. Mild to moderate myelopathy from single or two-level anterior compression can be treated with disc replacement if the other candidacy criteria are met — the decompression is equivalent to ACDF. The distinction is the degree of stenosis. When the canal compromise is severe enough to require 360-degree decompression, or when posterior elements must also be addressed, the anterior component is typically fusion. The myelopathy diagnosis alone does not determine the operation; the imaging does.
The comparison at a glance
| Factor | ACDA — Cervical Disc Arthroplasty | ACDF — Anterior Cervical Discectomy & Fusion |
|---|---|---|
| Decompression | Identical — disc removed, nerve decompressed | Identical — disc removed, nerve decompressed |
| Post-op motion | ✓ Segmental motion preserved | × Permanent elimination of segmental motion |
| Adjacent segment stress | ✓ Normal force distribution maintained | × Increased mechanical load on adjacent levels |
| Secondary surgery at 10 yr | ✓ Significantly fewer (Quinto et al. 2024) | × Higher reoperation rate |
| Hardware | Prosthetic disc only — no plate, no screws | Cage + anterior plate + screws |
| Approach | Anterior (same as ACDF) | Anterior |
| Levels | One or two levels (FDA-approved) | One to multiple levels |
| Best evidence for | 1–2 level DDD, no instability, normal facets, adequate disc height | Instability, severe facet arthritis, 3+ levels, severe OPLL, deformity |
The devices used here —
Simplify® and ProDisc-C®
Two cervical disc replacement devices are used here based on the anatomy and level of each case:
Simplify® Disc is a low-profile UHMWPE-on-titanium construct. Its flat, thin profile allows placement at cervical levels with limited disc height. FDA-approved for one- and two-level cervical disc replacement. The titanium shell integrates with the vertebral endplates; the polyethylene insert provides the articulating surface. The design allows natural coupled motion — simultaneous multiple-plane movement that characterises normal cervical kinematics.
ProDisc-C® is a metal-on-polyethylene ball-and-socket design with a fixed keel for primary stability. One of the most extensively studied cervical disc prostheses — the ProDisc-C FDA IDE data includes long-term follow-up and contributes to the cervical arthroplasty evidence base. The ball-and-socket articulation provides a defined center of rotation; the keel provides immediate rotational stability during bone ingrowth.
The choice between the two is anatomy-specific: disc space height, the level being treated, and the biomechanical demands of the case. Both are implanted through the same anterior approach as ACDF. Operative time is comparable. Both are MRI-conditional.
What the evaluation involves —
anatomy-specific, not algorithmic
Every consultation for cervical surgical disease includes a specific assessment for disc replacement candidacy alongside the standard ACDF assessment. The questions addressed for every candidate are:
1. Is the segment stable? Flexion-extension lateral X-rays assess dynamic translational motion at the operative level. Greater than approximately 3–3.5 mm of dynamic translation is a contraindication to disc replacement. This cannot be assessed from a supine MRI — it requires loaded, dynamic films.
2. What is the status of the facet joints? MRI axial sequences and, when needed, CT assess the facet joint architecture at the level being considered. The facets must be normal enough to tolerate preserved motion. Significant facet arthritis at the operative level shifts the decision to fusion.
3. Is there adequate disc height? Standing lateral X-ray and MRI sagittal sequences measure the remaining disc space. Most prostheses require a minimum disc height for proper seating and articulation. The lateral X-ray under standing load is more informative than the supine MRI for this assessment.
4. What is the nature of the compression? A soft or moderate disc herniation with predominantly discogenic compression is ideally suited to disc replacement. Significant OPLL is assessed carefully — moderate OPLL may still be managed anteriorly with ACDF, but extensive multilevel OPLL with significant canal compromise often changes the approach entirely, pointing toward posterior laminectomy and fusion or laminoplasty rather than any anterior operation.
5. How many levels? For one or two levels, disc replacement has the strongest evidence and FDA approval. For three or more, a hybrid approach or fusion is discussed based on the specific levels involved and the patient’s anatomy and goals.
This evaluation takes place at the consultation, with the actual MRI and standing X-ray films reviewed personally — not a radiology report. Candidacy cannot be determined from a report or a phone call. It requires the imaging.
If you have been offered only fusion for your cervical spine
This is the most common situation I see in second opinion consultations. A patient arrives having been told they need ACDF. The recommendation is often appropriate — the anatomy does support fusion, and fusion is the right operation. But in a significant proportion of cases, the anatomy would support disc replacement, and the patient was never told it existed. The reason is almost always the same: the surgeon recommending fusion is not certified for disc replacement.
Bring your cervical MRI and standing X-rays, including flexion-extension films if you have them. If you do not, they will be obtained at the visit. You can also submit your imaging securely before the consultation so the appointment goes directly to your anatomy and your options — not to reading films cold.
Get a second opinion before you decide.
A second opinion consultation will determine whether your anatomy supports cervical disc replacement — or confirm that ACDF is the right operation for you, and exactly why. Dr. Katsevman reviews all imaging personally. Certified for Simplify® and ProDisc-C®. Telemedicine available statewide — no travel required for the initial consultation.
Submit your cervical MRI, standing lateral X-rays, and flexion-extension films via the secure imaging portal before the appointment. Dr. Katsevman reviews all imaging in advance so the consultation focuses on your anatomy and your options.
References — PubMed-verified
- Quinto ES, Paisner ND, Huish EG, Senegor M. Ten-year outcomes of cervical disc arthroplasty versus anterior cervical discectomy and fusion: a systematic review with meta-analysis. Spine. 2024;49(7):463–469. doi:10.1097/BRS.0000000000004887
- Hu Y, Lv G, Ren S, Johansen D. Mid- to long-term outcomes of cervical disc arthroplasty versus anterior cervical discectomy and fusion: a systematic review and meta-analysis of eight prospective randomized controlled trials. PLoS One. 2016;11(2):e0149312. doi:10.1371/journal.pone.0149312
