TKR Revision

I had TKR in 2018, up until 8 months ago everything was great. I banged my knee on a oak table but had no pain. Since then I've been experiencing swelling and pain. Its been getting worse to the point I have constant pain and swelling. I know have to wear a brace because walking especially stepping up or down causes extreme pain. I've had blood tests, body scan , xray, test for gout all negative. The surgeon thinks there's nothing wrong, another Dr wants to do a nerve block. Any advice would be appreciated