I have the same thing. My head feels to heavy for my neck like it did right after my fusion. I had my ACDF of C5-C6 on May1st of 2007. I felt great afterwards. No pain in my left arm after 5 years of suffering. I just started having pain again this past September. I initially thought it was because of climate change from South Carolina to Washington State. It has continued to get worse. I wake up with my left arm throbbing and my thumb and the next two finger numb. I ache all along my shoulder blades, and I have been having excrutiating headaches almost dailey. I had an MRI recently it states that C5-C6 is the level of fusion. The central spinal canal and right foramen appear clear. The left foramen is less well seen and there is suspicion of disc or osteophyte causing moderate compromise. The artifact limits detail here. C6-C7, there is suggested minimal posterior disc bulge but no significant compromise of the spinal canal. The neural foramina are clear. I have an appoinment with a nuerosurgeon on April 14th, but I am anxiouse to find out what this all means.
As far as the surgery not taking, 5 years is way beyond the time limit for that. But, you could be having new problems in the C5-6, or from another level above or below the fusion. Why did you have the first fusion? Accident, or disc disease? Did the remove the disc? If you can give a little more information, might be able to answer your question better. Your sx sound like a nerve problem somewhere. You may need a MRI, to establish what is going on. Do you have a dr appt yet? Good luck, and just be careful not to furthur aggravate your neck until you see your dr, no heavy lifting, etc. Don't want to do any further damage.