Everybody is different, that's a given. With my tkr the infection left me with 2 more surgeries. One for a look see and a second to replace the tibia portion of the device. I don't have pain but regaining rom was never accomplished to my satisfaction, even after 2 manipulations.
Now, at 17 months post surgery my extension is good, but my flexion hasn't improved substantially. I must say that by my own physical therapy practice of going up and down stairs has helped, especially down. Given that I'm much happier now with just 10% more range. Good luck to all.