I am scheduled to have acdf fusing C 3-4 and C6-7, with the use of the ROI-C cage. By the time this surgery is finished I will have 4 levels fused. (C4-5 fused in 2011 with plate and screws and c 5-6 are genetically fused). I'm nervous to say the least. Can anyone provide me some info on the Roi-c cage? And what are the effects after having 4 levels fused.