Hey Fred, the short answer is work through it. Pain is to be expected because you’ve had it locked up so long, and the body’s natural inclination is form a contracture. Breaking it is going to suck and hurt, and I know that from when my mom had a bilateral TKR and I had to sit on her knees. She’s one of the toughest women I know, but she was close to crying from the pain. It’s like, you can hurt yourself now and get back to normal, or you can reist the pain and be on discomfort and pain for the rest of you life because your knee can do what it’s meant to. Try popping a couple painkillers before you bend so it takes the edge off.