I have been told i have r arthritis in my knees and other joints but i'm not sure. If i slightly knock my joints, especially my knees or shoulder, they bruise and swell up and are so painful,this starts within 1-2 seconds, that i can't walk or stand up and stays that way for at least 2 days. I cannot bend my knees or elbows for more than 3 minutes at a time.