@nhbfan EMG's detect when a muscle does not receive nerve impulses or receives an abnormal pattern of nerve impulses. If stenosis is at the nerve roots, a dermatome map shows where those nerves go in the body. Here is an explanation.
https://my.clevelandclinic.org/health/articles/22278-cervical-spine
If stenosis is in the central spinal canal, it is hard to tell which nerves are affected below that level, but that can be general things. I do know that cervical spine issues cause muscle spasms in the neck in muscles which also connects to the scapula, so I think you can feel pain there. I did with my C5/C6 central canal stenosis. I didn't have any nerve root stenosis.