Cervical Disc Arthroplasty

Surgical Indications for Cervical Disc Arthroplasty?

Single-level cervical radiculopathy due to degenerative disc disease: Cervical disc arthroplasty (CDA) is indicated for patients with single-level cervical radiculopathy from degenerative disc disease who have failed appropriate conservative management. Multiple randomized controlled trials and meta-analyses demonstrate that CDA provides outcomes comparable or superior to anterior cervical discectomy and fusion (ACDF) in selected patients, with benefits including lower rates of secondary surgery and better preservation of motion. The literature supports use in both one- and two-level disease, provided there is no significant instability, deformity, or severe facet arthropathy (Joaquim et al., 2019; Chen et al., 2024).
Symptomatic radiculopathy due to herniated nucleus pulposus: CDA is appropriate for patients with radiculopathy (arm pain, numbness, or weakness) refractory to at least 6 weeks of conservative therapy, or sooner if there is progressive neurological deficit. This is supported by randomized trials and meta-analyses showing efficacy and safety of CDA in this population (Joaquim et al., 2019; Hu et al., 2016; Gao et al., 2015; Gutman et al., 2018).
Cervical myelopathy: CDA is an option for select patients with mild to moderate cervical myelopathy due to one- or two-level degenerative disc disease, provided exclusion criteria such as instability, kyphotic deformity, or severe facet degeneration are absent. Recent reviews and comparative studies confirm that CDA can be considered in this context, with outcomes similar to ACDF in appropriately selected patients (Tu et al., 2023; Ko et al., 2023).

Absolute Contraindications to Cervical Disc Arthroplasty

Active local or systemic infection (Auerbach et al., 2008; Joaquim et al., 2019; Nunley et al., 2018)
Severe osteoporosis (Auerbach et al., 2008; Joaquim et al., 2019; Nunley et al., 2018)
Allergy or sensitivity to implant materials (Auerbach et al., 2008; Joaquim et al., 2019)
Advanced spondylosis with bridging osteophytes or spontaneous fusion at the index level (Patel et al., 2024)
Marked cervical instability (e.g., translation >3.5 mm or angulation >11°) (Auerbach et al., 2008; Joaquim et al., 2019; Nunley et al., 2018)
Severe facet arthropathy at the index level (Auerbach et al., 2008; Joaquim et al., 2019; Nunley et al., 2018)
Ossification of the posterior longitudinal ligament (OPLL) with retrovertebral compression (Joaquim et al., 2019; Tu et al., 2017)
Significant loss of disc height (>75% of original height) (Patel et al., 2024)
Segmental kyphosis >10° at the index level (Patel et al., 2024)
Prior cervical fusion at the index level (Auerbach et al., 2008; Joaquim et al., 2019)

Relative Contraindications to Cervical Disc Arthroplasty

These are areas that are debated among spine surgeons.

Segmental kyphosis 5–10° at the index level (Patel et al., 2024)
Loss of disc height 50–75% (1.5–3 mm) (Patel et al., 2024)
Bridging osteophytes without complete ankylosis (Patel et al., 2024)
Less-mobile disc (preoperative range of motion ≤5°) (Tu et al., 2019)
Grade 1 or less spondylolisthesis. There is emerging anecdotal evidence supporting the use of cervical disc arthroplasty (CDA) in patients with grade 1 spondylolisthesis. Though robust data does not yet exist.
Mild facet arthropathy (Nunley et al., 2018). There are some spine surgeons that have observed cervical disc arthroplasty offloads the forces across the facet joints allowing patients to preserve motion at the operative level.
Poor general medical condition or high anesthetic risk (McAfee, 2004)
Hybrid constructs, which combines anterior cervical discectomy and fusion (ACDF) with cervical disc arthroplasty (CDA), is supported by moderate-quality evidence as a safe and effective option for multilevel cervical degenerative disc disease and is non-inferior to multilevel ACDF in terms of safety and efficacy (Yang, 2020; Hollyer 2020; Xiong, 2018; Kim, 2023).
Age is considered a relative contraindication to cervical disc arthroplasty (CDA), but not an absolute one. Early clinical trials and device labeling for CDA typically limited inclusion to patients between 18 and 60 years, reflecting concerns about poorer bone quality, higher rates of spondylosis, and comorbidities in older adults. However, more recent evidence suggests that CDA can be performed safely and effectively in selected elderly patients. Multiple studies have shown that while older patients (typically ≥65 years) may have slightly different perioperative profiles—such as a trend toward increased perioperative complications or a small reduction in segmental range of motion—clinical outcomes, complication rates, and prosthesis mobility are generally comparable to those in younger patients over short- and mid-term follow-up. (Wu, 2019; Ajoku, 2023). Notably, a retrospective cohort analysis found no significant differences in clinical or functional outcomes between typical candidates and those with relative contraindications, suggesting that strict age cutoffs may be unnecessarily restrictive (Patel, 2023).
Axial neck pain. Meta-analyses and systematic reviews confirm that CDA is effective for both neck and arm pain in appropriately selected patients, and that the presence of axial neck pain alone does not preclude favorable outcomes. Therefore, current evidence supports that axial neck pain is not a relative contraindication to cervical disc arthroplasty (Gao, 2015, Cepoiu, 2011; Gao, 2013; Zara’s, 2024).
Prior fusion at index level: There is early research by a few surgeons that consider taking down previously fused levels to convert them to disc arthroplasty, but this is still experimental. More studies are needed.
Multilevel disease (>2 levels): The current evidence indicates that cervical disc arthroplasty (CDA) at three or four levels is feasible and can be safe and effective in carefully selected patients, but high-quality data are limited and this remains a relative contraindication. Most robust evidence and FDA approvals are for one- or two-level CDA, with strong support for safety, efficacy, and motion preservation in these settings. For three- and four-level CDA, the literature consists primarily of retrospective series, systematic reviews, and meta-analyses, which suggest that outcomes—including pain relief, functional improvement, and preservation of motion—are comparable to single- and two-level CDA, and may be superior to multilevel ACDF in terms of adjacent segment degeneration and overall motion (Tu, 2023; Joaquim, 2017; Alves, 2021; Wu 2017; Zhao, 2015).

Does Cervical Disc Arthroplasty Prevent Adjacent Segment Disease?

Cervical disc arthroplasty (CDA) is associated with a lower incidence of adjacent segment disease (ASD) compared to anterior cervical discectomy and fusion (ACDF), but it does not completely prevent ASD. Multiple high-quality meta-analyses and randomized controlled trials demonstrate that CDA reduces the risk of both radiographic adjacent segment degeneration and clinically significant ASD, as well as the need for adjacent segment reoperation, relative to ACDF over mid- to long-term follow-up (Latka et al., 2019; Foley et al., 2024; Zhu et al., 2016; Toci et al., 2022; Luo et al., 2018; Dong et al., 2017). For example, pooled data from meta-analyses show a statistically significant reduction in ASD and reoperation rates with CDA versus ACDF, with risk ratios for ASD and reoperation favoring CDA.

However, the absolute risk of developing ASD is not eliminated by CDA, and some studies with long-term follow-up report that the difference in clinically significant ASD or reoperation rates may not always reach statistical significance, or that the benefit may diminish over time (Ghobrial et al., 2019; Goedmakers et al., 2023; Verma et al., 2013; Yang et al., 2012). Notably, a recent double-blinded randomized controlled trial found no significant reduction in clinically relevant adjacent segment disease at five years with CDA compared to ACDF (Goedmakers et al., 2023).

In summary, CDA reduces but does not fully prevent adjacent segment disease when compared to ACDF, and the magnitude of benefit may vary depending on patient selection, prosthesis type, technique, and duration of follow-up.

Complications

Revision surgery rates for CDA are low: 1.2% at 5 years, 7% at 7 years, and 10% at 20 years, all lower than for ACDF (9–42% depending on duration and cohort). Device failure requiring removal is rare. Other complications such as prosthesis subsidence, segmental kyphosis, and instability are each reported in 1–3% of cases. (Sasso, 2024)
Implant migration: The most common device-related complication leading to revision, with rates of 23.5% among revision cases in the FDA MAUDE database, and 25.2% of all reported complications in a large cross-sectional analysis. Device-specific rates vary, one study showed that out of 678 revisions, Mobi-C (239), M6 (167), Prodisc-C (88), Prestige (60), PCM (44), Bryan (35), Secure (23), Simplify (21), and Discover (1), migration was the most complication for these devices, Mobi-C (26.4%), Prodisc-C (21.3%), Prestige (24.6%), PCM (84.1%), Bryan (48.6%), Secure (30.4%), and Discover (100%). For M6, the most common complications associated with revision surgery were osteolysis (18.6%) and neck pain (18.6%), while neck pain (23.8%) was the most common for the Simplify. (Altorfer, 2024; Virk, 2020)
Heterotopic ossification (HO): Radiographic HO is frequent, with rates of 51–69% at 3–10 years. High-grade HO (fusion or severe ROM limitation) occurs in 16–46% of cases, but does not consistently correlate with worse clinical outcomes. HO is also associated with increased risk of adjacent segment degeneration (ASD). (Hui, 2020; Liang, 2020; Dufour, 2019)
Neck pain (persistent or recurrent): Accounts for 15.5% of revision cases and 15.2% of all reported complications. (Altorfer, 2024; Virk, 2020)
Dysphagia: The most common early complication, with pooled rates of 4.7% at short-term follow-up and 6.2% in noncontiguous CDA. Rates are lower than with ACDF. ((Hui, 2020; Baumann, 2024)
Osteolysis: Rates are highly implant dependent. For the M6 device, some studies showed that the prevalence of osteolysis was 44% with a mean follow up 8.1 years (6.5-11 years) with a 34-36% revision rate within mid-term follow up mean 8.1 years (Hackel, 2024; Scott-Young, 2022). Among high volume disc arthroplasty surgeons there is anecdotal evidence that the Simplify disc may have a higher risk of osteolysis at 5-7 years of follow up, further studies are being done currently to delineate this risk. Other implants have not shown to have high osteolysis rates at this time.
Surgical site infection: Rare, with rates of 0.59% at 30 days and 3 months. (Naya, 2023)
Revision surgery: Cumulative revision rates are 1.2% at 5 years, 6.9% at 6 months, and up to 10% at 20 years, generally lower than ACDF. (Altorfer, 2024;Naya, 2023)
Adjacent segment degeneration (ASD): Radiographic ASD occurs in 36–55% at long-term follow-up, but symptomatic ASD requiring surgery is lower for CDA (0–6.9%) than ACDF (6.4–15.8%). (Hui, 2020; Baumann, 2024; Foley, 2024)
Radiculopathy: Reported in 8.1% of device-related complications. (Virk, 2021)
Vascular injury: Very rare, with rates below 1%. (Hui, 2020; Loidolt, 2021)
Other complications: Insertion problems/failure and polyethylene wear are reported but are uncommon. (Virk, 2021; Foley, 2024)