Right arm and uppper back weakness

My right arm and upper back & shoulder have gone quite weak twice in the last month.  Also I have a sporadic twitch either in my right or left eyelid (currently my left) and it lasts for days and days.  I am supposed to have surgery to fuse C5-C6-C7 on May 15th because of dessicated disks and possible pressure on my spinal cord and surrounding nerves by 5 osteophytes.  Also I have stenosis in that area.  I have very little pain though, and I am scheduled for another MRI next week prior to surgery.   I am a 50 year old female and my last bone density test came out great, no signs of weakening bones at all.  
My concern is that I will have this surgery and it won't solve the problem but just create new ones.  I had an EMG and was negative for any nerve damage.  I also had a brain MRI and a brain stem vascular MRI (both without contrast) about 8 months ago because of migraines 3-4 times a week.  I am now on Lyrica and the migraines have just about disappeared.  I was on Topamax for 10 months and I could never adjust to it, and the headaches continued.  Both MRI's were negative.  So I can hopefully rule out a brain tumor with these MRI results?  If my cervical spine MRI next week shows progressively worsening results from the last one in 3/07, I guess I can blame my symptoms on my c-spine, but if it does not show any more damage, is it possible my symptoms are not related to my c-spine?   The weakness is very frightening, I have a hard time writing or holding a heavy object in my right hand.
The only pain I have is when I turn my head to either side, the left side of  my neck and my entire upper spine feel sore.  Sometimes I have shoulder pain mimicking bursitis in the front area of either shoulder.   Am I correct in assuming that the symptoms are probably due to the C-spine or maybe not?   And what about the eyelid twitches?  How could they possibly be related to my neck?

Thanks for your help!

Janice