Anything that "remodels" the spinal cord can be serious. Plus, the C5-6 that reduces the spinal cord to 7mm is nothing to SNEEZE at. I would DEFINITELY get another opinion!!! Something isn't right here, and I'm not sure what's going on, but it sounds like you have good reason for pain!
I would get a referral to another NEUROSURGEON, or call one myself!!1 Take your films AND the report, and see another one. I think something's wrong here. I'm NO DOCTOR, but the cord shouldn't be reduced to 7mm from what I've read.
Best of luck and PLEASE -- will you let me know what the other doctor says? I'd really like to know. Big hugs, Lee