I don't pretend to have any answers for you but my first TKR was on my right leg and I had been bone on bone for about 15 years prior and had bi-lateral arthroscopic surgery. After my first knee in September of 2011 I had terrible flexion and ROM of about 100 degrees after PT. My surgeon sent me to a more aggressive PT and we saw improvement but he was pushing the limits of pain. My total PT out patient was 18 weeks. I also had scar tissue which felt like a small golf ball on the outside of my knee. This was limiting my mobility and what I found was a tool that runners use on their muscles which resembles a small, about 1", rolling pin. The rollers were about 1-1/2" -2" long and maybe 6-7 of them. Rolling the scar tissue for 5-10 minutes each day several times a day while exercising caused the tissue to "recondition" or maybe break up is a better term over several months time. This scar tissue was where the tendon was reattached. It hurts in the beginning but gets better in time.
Getting better flexion was accomplished by sitting on a chair and resting my straightened led, with a small towel rolled up under the heel, my frozen gel pack on the knee and a 5 pound weight for 10-15 minutes at first. Later the weight was upped to 10 pounds and the stretches lasted 30 minutes. It worked wonders for me. Although the more aggressive PT was painful it was well worth the effort. There were times I had to tell him he went too far but then he would adjust. This knee took a long time but when it healed it was so much better. I actually looked forward to getting the other knee done which was done this past November, the Monday after Thanksgiving.
That knee, the left one, was a totally different experience. The day after surgery I was sitting on the side of the bed and bending it 95-100 degrees. It took many weeks to get the right knee there. There was no scare tissue like the right knee. I still had issues with pain management as most pain meds don't work well for me but it went so much smoother. I'm still working on getting the muscles back in shape and back to working squad with some discomfort although I don't do any heavy lifting. At 59, I look forward to getting my EMT status and doing all those things I enjoy, fishing, RVing, and traveling.
Hopefully some of this may be helpful. The pain is real and hopefully will subside over time. It did for me but then again each TKR is different. I avoided MUA by more aggressive PT as recommended by my surgeon. I'm glad we went this way and I used the same surgeon for both knees. I didn't need the aggressive PT for the second knee. This is similar to what I used broken link removed: https://www.dickssportinggoods.com/product/index.jsp?productId=12842589&gsidynamic=GooglePLA-_-SOCKS/RUNNINGACCESSORIES-_-SOCKS/RUNNINGACCESSORIES-_-SKU-12660283&camp=CSE:GooglePLA:12842589:12660283:SOCKS/RUNNINGACCESSORIES-broken link removed: https://www.thestick.com/cgi-bin/commerce.cgi?preadd=action&key=G-1750
United States
I have an appointment with an ortho doc at the Mayo Clinic in MN at the end of July. It can't come soon enough. I have been in pain since December, with little relief, except when I can't take it anymore and take a percoset. My ROM is still the same (about 25-90 degrees). Everyday things, like food shopping are exhausting. I hope and pray
that this doctor can find the magic needed to fix my knee and make me feel like a normal person once again. 
I will keep all of you in my thoughts and prayers!!!!
! But it sound to me like you are headed in the right direction and hopefully you get the answers and relief you need at the Mayo Clinic.
Hang in there my friend, focus on that holiday you want to take with the children & remember, we are all here for you 
Jaki x
