Q: My sister has acute pain in her legs and arms. There is some swelling and she can barely get up in the morning and move. She went to the doctor and had an x-ray which was normal. She has been taking Motrim for the pain.

A:When a patient presents with pain in the legs and the arms, there are three broad categories of diseases which should be looked for: 1. first is what is referred to as auto-immune diseases where the body attacks itself. Diseases in this category include different forms of myositis, 2. neurological diseases especially involvement of the cervical spine, and 3. diseases the cause of which is not understood at all and include conditions such as polymyalgia rheumatica. You mention your sister has edema and this makes me think that possibility number 1 is most likely. Only after a detailed evaluation including the appropriate investigations can the cause be determined X-rays will be normal in all these conditions.