Long-term Outcomes of the US FDA IDE Prospective, Randomized Controlled Clinical Trial Comparing PCM Cervical Disc Arthroplasty With Anterior Cervical Discectomy and Fusion.

STUDY DESIGN

Prospective, multicenter, randomized clinical trial.

OBJECTIVE

To evaluate the long-term safety and effectiveness of the PCM Cervical Disc compared with anterior cervical discectomy and fusion (ACDF) in treatment of patients with symptomatic single-level degenerative spondylosis between C3-C4 and C7-T1 with or without prior cervical fusion.

SUMMARY OF BACKGROUND DATA

The 2-year results of the PCM Cervical Disc trial have been reported previously. The current study reports the long-term results of the same trial.

METHODS

Patients with single-level cervical spondylosis and radiculopathy with or without myelopathy unresponsive to nonoperative treatment were enrolled. The per protocol patient sample at 5 years included 293 patients (163 PCM, 130 ACDF). Adverse events and secondary surgical procedures are reported on the cohorts through current follow-up, which include 110 patients (68 PCM, 42 ACDF) at 7 years.

RESULTS

At 5 years postoperative, all patient-reported outcomes-neck and arm pain visual analogue scale score, neck disability index, and general health (36-Item Short Form Health Survey physical and mental component scores: physical component summary, mental component summary)-were significantly improved from baselines in both groups, and mean scores were significantly better in the PCM group for neck disability index (P=0.001), neck pain (P=0.002), general health (Pphysical component summary=0.014; Pmental component summary=0.004), and patient satisfaction (P=0.005). PCM patients trended toward fewer 2- to 7-year device-related serious adverse events (1/214, 0.5% PCM; 2/190, 1.1% ACDF) and secondary surgical procedures (7/211, 3.3% PCM; 14/290, 7.6% ACDF). Adjacent-level degeneration was radiographically more frequent after ACDF (33.1% PCM, 50.9% ACDF; P=0.006) and was the primary indication for the increase in late-term secondary surgical procedures after ACDF.

CONCLUSION

The long-term results show good clinical outcomes after ACDF and PCM arthroplasty. PCM patients showed greater improvement in neck disability index and neck pain scores with a lower rate of radiographical adjacent-level degeneration and a trend toward fewer secondary surgical procedures. These data support PCM arthroplasty to be a viable and sustainable alternative to ACDF.

LEVEL OF EVIDENCE