Table 5. Pain and disability.

Outcomes	Strength of evidence	Conclusions/comments
1. VAS – neck and arm pain		Significantly greater mean improvement from baseline in all outcomes in the Bryan C-ADR group compared with the ACDF group at 48 months. Only the NDI showed greater mean improvement from baseline in the Prestige C-ADR group compared with the ACDF group at 60 months.
2. NDI
3. Quality of Life – SF-36 PCS
4. Success Overall/NDI		Overall success and NDI success, which were only reported by the Bryan trial, were achieved in a significantly greater proportion of C-ADR patients compared with ACDF patients at 48 months. At both 48 (Bryan) and 60 months (Prestige), more patients achieved neurological success following C-ADR compared with ACDF.
Neurological
5. ASD		The rates of ASD at 48 (Bryan) and 60 months (Prestige) were not statistically different between treatment groups.
6. Return to work		At both 48 (Bryan) and 60 months (Prestige), more patients were working following C-ADR compared with ACDF.

Complications
Outcomes	Strength of evidence	Conclusions/comments
1. Reoperation		Significantly fewer revisions, supplemental fixations, and use of external bone growth stimulators were reported in the Prestige C-ADR compared with the ACDF group at 60 months. Rates of WHO grade 3 or 4 adverse events were similar between groups at 48 months in the Bryan trial.
2. Adverse events