My left knee was replaced almost 20 yrs ago and has begun to hurt and feel stiff especially when i do steps!!!!

ConsultYourOrthopod: The artificial joints used 20 years ago were not everlasting and had a life after that it needs to be replaced.Consult your Orthopedic Surgeon if he/she is still around or another one and see if your artificial knee needs to be replaced by a new one

See ortho: Uncertain if you have osteoarthritis or an autoimmune disorder. You need to contact an orthopedic surgeon first then go from there.