I know exactly what you are experiencing. I’m only 8 weeks out after having a left tkr and I have been experiencing pain and sensitivity for awhile now. My doctor said it was nerve pain due to the nerves reawakening after surgery. He suggested taking Gabapentin. It helps very little though and pain pills only help for a very short time. I can’t stand for anything to touch it either. The only thing that I find that helps me some is that I have a cold therapy machine with a knee wrap that I use when it gets to hurting and it seems to help for a while. I usually place a small hand towel between it and my skin so it’s not too extremely cold. I also have a very thin pillow that I use to sleep with between my knees . I haven’t experienced any muscle spasms. I do have pain just about all the time now. Sorry to hear that you are having so much trouble. I hope things get better for you soon!