I really appreciate your experiences. I had found nothing else that seems so similar to my condition, and both of us 66. It reminds of a saying; something like "people often mislabel someone as a cynic, when they are just someone who sees things clearly"
I am 11 weeks now, still on crutches and any tiny exercise or even being on my feet for 30 minutes causes me pain for 2 days.
I tested negative for infection last week. I know it's stupid, but I was almost hoping it was positive in order to get a definitive diagnosis.
Like you, I have been on serious painkillers the whole time, but now every painkiller including even a simple tylenol gives me a rebound headache that lasts all day (better ID'd as medication overuse headache), a big problem.
Best wishes for your surgery and recovery, please keep us informed.