@annie1 I'm glad you are working with a rehab doctor. I know you are worried about nerve damage and I was too with bone spurs pressing into my spinal cord for 2 years, and I did fine. We are all different of course and the best one to advise you about when nerve damage would begin would be your providers. I found this information from the National Library of Medicine that may be of interest.

Spinal Stenosis and Neurogenic Claudication
https://www.ncbi.nlm.nih.gov/books/NBK430872/
You mentioned getting cramps and throbbing pain your calves. Cramps and spasms happen when nerves are irritated and sending signals to a muscle. In biology class, we did some experiments with sending electric shocks to see when the responses changed from a twitch response to a sustained contraction (as in a cramp) and found the frequency and speed of signals that made that happen.

I wouldn't worry that permanent nerve damage has already set in, just do the best you can at rehab. You would probably notice something like that if a function just disappeared and stopped working, but do ask your rehab doctor that question.

Jennifer