RN here. Last job was on a post-op ortho unit. Mostly hip/knee replacements. Hopefully, the pre-op procedure will answer many of your questions. Prepare to be laid up for awhile.
I will say from experience. People that have been in lots of pain will sometimes, 'self-medicate'. IOW: If the patient has been using excessive alcohol or prescription medications-they may have developed a tolerance or addiction. The post-op pain meds will not be as effective if you are used to mega doses. Also, if the patient has developed an alcohol addiction-there will be the issues of detox, (DTs) after surgery. Even a few beers every night can trigger withdrawal symptoms. Be honest with the surgical team, if any of this may be an issue. Good luck, I hope you will be pain-free and more mobile, soon.