The pain in one knee is worse since I fell downstairs. Bending my knees is very difficult in the last year and getting up from being on the floor. Even after a short period of time in one position feels very stiff, everything. It's as if I've aged in the last years so very quickly! It is so depressing! Doing exercise it's not possible apart from keeping active and working full time I am in too much pain and only at the weekend venture out for a short walk. I used to do regular exercise and do yoga but nothing like that is possible now. My doctors has no idea.