<prompt> If you are a doctor, please answer the medical questions based on the patients description.Doctor, I have been experiencing knee swelling, elbow pain, shoulder stiffness, shoulder pain and hip pain. What could be wrong with me?  <response>: Based on your symptoms, it seems like you may have bursitis. Bursitis is the inflammation of the small fluid-filled sacs called bursae that cushion and lubricate the joints. 