The Norwegian Cervical Arthroplasty Trial (NORCAT): 2-year clinical outcome after single-level cervical arthroplasty versus fusion—a prospective, single-blinded, randomized, controlled multicenter study

Abstract

Purpose Standard surgical treatment for symptomatic cervical disc disease has been discectomy and fusion, but the use of arthroplasty, designed to preserve motion, has increased, and most studies report clinical outcome in its favor. Few of these trials, however, blinded the patients. We, therefore, conducted the Norwegian Cervical Arthroplasty Trial, and present 2-year clinical outcome after arthroplasty or fusion. Methods This multicenter trial included 136 patients with single-level cervical disc disease. The patients were randomized to arthroplasty or fusion, and blinded to the treatment modality. The surgical team was blinded to randomization until nerve root decompression was completed. Primary outcome was the self-rated Neck Disability Index. Secondary outcomes were the numeric rating scale for pain and quality of life questionnaires Short Form-36 and EuroQol-5Dimension-3 Level. Results There was a significant improvement in the primary and all secondary outcomes from baseline to 2-year follow-up for both arthroplasty and fusion (P \ 0.001), and no observed significant between-group differences at any follow-up times. However, linear mixed model analyses, correcting for baseline values, dropouts and missing data, revealed a difference in Neck Disability Index (P = 0.049), and arm pain (P = 0.027) in favor of fusion at 2 years. The duration of surgery was longer (P \ 0.001), and the frequency of reoperations higher (P = 0.029) with arthroplasty. Conclusion The present study showed excellent clinical results and no significant difference between treatments at any scheduled follow-up. However, the rate of index level reoperations was higher and the duration of surgery longer with arthroplasty.

Artificial disc replacement versus fusion in patients with cervical degenerative disc disease and radiculopathy: a randomized controlled trial with 5-year outcomes

“…3,8,11,20,21,25,27 The only double-blinded RCT, however, displayed higher NDI scores and more arm pain in the arthroplasty group after 2 years. 34 In our study, there were fewer reoperations in the fusion group than in the ADR group and the incidence of nonunion was low. Our results contradict other large RCTs with a 5-year follow-up, 3,8 i.e., they reported a higher frequency of secondary surgery in the control group compared with the ADR group, mostly because of nonunion.…”

“…The results of that study were in favor of fusion surgery. 34 Complications after ADR surgery occur, including spontaneous fusion and loosening. 6,14,33,38 None of the larger open-label randomized controlled trials had long-term follow-up with MRI.…”

A randomised controlled trial comparing the effectiveness of surgical and nonsurgical treatment for cervical radiculopathy

“…is the most commonly used procedure at the neurosurgical department of Oslo University Hospital. This strategy is supported by a recent randomised controlled trial at our hospital that found no clinical benefits of disc prosthesis [22]. All operations will be carried out by experienced and qualified neurosurgeons.…”

“…Further, the disc prosthesis (cervical arthroplasty) has been proposed to improve results. A recently published Norwegian multicentre trial did not favour discectomy and disc prosthesis compared with the traditional discectomy and fusion [22]. The trial included patients with one-level radiculopathy (C6 or C7) primarily caused by spondylosis.…”

“…A systematic review reported that MCIC varied from 10 to 38, on a scale from 0 to 100 [24]. An MCIC of 10 is most commonly used in trials comparing various surgical procedures for cervical radiculopathy [22]. The global perceived change is often used as an external criterion for estimating MCIC; however, the improvement expected by the patient in order to undergo surgery or non-operative treatments has not been examined, to the best of our knowledge.…”