Single-Level Cervical Disc Replacement Using a PEEK-on-Ceramic Implant: Results of a Multicenter FDA IDE Trial With 24-Month Follow-up

Abstract

Background: Many early cervical total disc replacements (TDRs) produced motion through a ball-and-socket action, with metal endplates articulating with a plastic core. Polyetheretherketone (PEEK) is used increasingly for spinal implants due to its mechanical properties and lack of artifacts on imaging. A TDR was designed with titanium-coated PEEK endplates and a ceramic core. The purpose of this study was to compare this TDR with anterior cervical discectomy and fusion (ACDF) to treat single-level cervical disc degeneration.Methods: This was a prospective, nonrandomized, historically controlled, multicenter US Food and Drug Administration (FDA) Investigational Device Exemption (IDE) trial. Patients received the PEEK-on-ceramic Simplify t Cervical Artificial Disc (n ¼ 150). The historic control group included 117 propensity-matched ACDF patients from an earlier IDE trial. The primary outcome was a composite success classification at the 24-month follow-up. Outcome measures included the Neck Disability Index (NDI), neurological status, adverse events, subsequent surgery, a visual analog scale assessing neck and arm pain, and the Dysphagia Handicap Index. Radiographic assessment included flexion/extension range of motion and heterotopic ossification. Facet joints were assessed at 24 months using MRI.Results: The success rate was significantly greater in the TDR group vs the ACDF group (93.0% vs 73.6%; P , .001). Mean NDI, neck pain, and arm pain scores improved significantly in both groups at all follow-up points. Mean NDI scores in the TDR group were significantly lower than ACDF scores at all follow-up points. There were no significant differences in the rates of serious adverse events. The range of motion of the TDR level had increased significantly by 3 months and remained so throughout follow-up. Facet joint assessment by MRI in the TDR group showed little change from preoperation.Conclusions: The TDR had an acceptable safety profile and a significantly greater composite success rate than ACDF. These results support that the PEEK-on-ceramic TDR is a viable alternative to ACDF for single-level symptomatic disc degeneration.Clinical Relevance: This study found that the PEEK-on-ceramic TDR is a viable treatment for symptoms related to cervical disc degeneration and offers similar or superior outcomes compared with fusion.

Ceramics in total disc replacements: A scoping review

“…NDI scores of patients who received TDR were significantly lower, i.e. superior (Geisler et al, 2019;Gornet et al, 2019b;Guyer et al, 2021;Phillips et al, 2013) or not statistically different (Shi et al, 2016), when compared to fusion outcomes.…”

“…Here, overall success was defined as improvement of Neck disability index (NDI) ≥ 7.5 points, no neurological worsening, no serious adverse events related to implant or implantation (related SAE), no secondary surgery due to treatment failure. With a similar definition, (Guyer et al, 2021) found success in 93% of TDR and 73.6% of fusion patients 2 y. p.o. (NDI improvement value converted to 50 point scale).…”

“…The percentage of patients who received a ceramic TDR with clinical outcome rated as "excellent" or "good", according to Odom's criteria, ranged from 76% (single level group) (Pimenta et al, 2007) to 100% (Ramadan et al, 2007). Statistically significant superiority of overall success compared to fusion was reported in the few studies that made this comparison (Gornet et al, 2019b;Phillips et al, 2013;Guyer et al, 2021).…”

“…Mean reported NDIs range from 6.8 (Guyer et al, 2021) to 14.80 (facet tropism group) (Liu et al, 2021) for TDRs that use ceramics for articulation, and from 5.77 (Shi et al, 2016) to 23.8 (Choi et al, 2012) for TDRs that use ceramics for osseointegration (0-50 scale, converted when reported differently). NDI scores of patients who received TDR were significantly lower, i.e.…”

Cervical Total Disk Replacement

“…The patient selection criteria and detailed descriptions of the study populations have previously been described in detail. 14,15 In both groups, the primary indication for TDR was cervical disk disease with radiculopathy and/or myelopathy from C3 to C7, unresponsive to at least 6 weeks of nonoperative care progressive symptoms, and/or compression of neural tissue. The primary exclusion criteria were: severe facet joint degeneration marked cervical instability, or prior cervical TDR, or anterior cervical discectomy and fusion.…”