Wow, what an ordeal. I too had a TKR in January 2018. I had scar tissue as well. Pain and swelling in my knee still exist although the swelling has diminished some. I had a nerve block which helped with the pain and swelling and nerve damage. I’m no doctor but when you are having a TKR nerves are cut and symptoms start presenting themselves. Therein lies the problem, surgeons have no idea (my surgeon for one) how or why their patient is complaining of stiff knee, band tightness, tinkling and sharp pains in knee. Crazy. I went to a pain management/orthopedic clinic and was diagnosed immediately with Complex Regional Pain Syndrome (CRPS), there is no cure but there is relief with the nerve block. Hope this helps, stay focused on good thoughts. Stay away from anymore surgery on that knee. Best wishes for relief.