Prospective, Multicenter Study of Two-Level Cervical Arthroplasty With a PEEK-On-Ceramic Cervical Total Disc Replacement: Five-Year Follow-Up.

STUDY

DESIGN

Prospective, nonrandomized cohort analysis.

OBJECTIVE

To evaluate five-year outcomes of patients treated with a polyetheretherketone (PEEK)-on-ceramic cTDR device at two levels for radiculopathy and/or myelopathy.

BACKGROUND

Cervical total disc replacement (cTDR) has gained acceptance as a treatment for symptomatic cervical degenerative disc disease (DDD). Long-term follow-up studies are required to further assess clinical and radiographic outcomes, specifically for patients treated at two consecutive levels.

METHODS

Patients implanted with Simplify Cervical Disc at two levels from C3 to 7 as part of a Food and Drug Administration investigational device exemption trial (NCT03123549) were contacted, consented, and prospectively followed from 36 to 60 months.

RESULTS

Of 181 patients treated, 80% (144) completed five-year follow-up. Composite clinical success was 86% at 60 months versus 88% at 24 months. At 60 months, 95% had a minimum 15-point improvement in Neck Disability Index compared with 93% at 24 months. Mean neck pain improvement at 24 months (-6.1 on a 10-point numeric scale) was maintained at 60 months. Similarly, improvements in arm pain scores were also maintained from -5.7 at 24 months to -6.2 at 60 months. The cumulative five-year index level reoperation rate was 5% (1%/year) and the adjacent level reoperation rate was 2.2% (0.4%/year). Segmental range of motion was maintained at both operated segments through five years, with an average of 9.0° at superior and 8.7° at inferior levels. Bridging bone was identified in 1% of both the superior and inferior levels, 6% of superior levels only, and 6% of inferior levels only.

CONCLUSIONS

This intermediate five-year follow-up study augments previously reported two-year results, supporting that the Simplify cTDR is safe and effective for the treatment of two-level symptomatic cervical DDD. Statistically significant improvements in pain and disability at two-year postoperative were maintained or improved at five years with preservation of motion and low reoperation rates at index and adjacent levels.