I have had a C5-C7 fusion has been in for 20 years apparently as of last year there have been no visual ( MRI ) changes but I noticed that my fingers last year's right hand this year add left hand they are somewhat numb and tingling. My PCP ordered an EMG and it showed there was a deficit in nerve impulses ( if that was the terminology they used in the report, I haven't read it for such a long time. So, perhaps you might ask your doctor if they could order an EMG if you haven't done it already, to see if what has happened to you is the result of your spinal problems but think about it everything with the nervous system can be a hide and seek. A two-hour seizure and still clearly talking ( I still remember some questions) during parts of it, and then it stopped. Pain, weakness, flaccidity, all can even be the result of the way you turn or bend your arm wrist, etc. and until it happens again or gets worse until you capture it you'll have to keep an eye on times when maybe your hand/fingers feel just a little different and write it down; not to go right away to the doctor unless you think it emergency like a stroke - like one-sided weakness, slurring of speech etc. but so you can tell him/her " it happens a little bit when I've done this." Well again just some ideas Take care