Knee Pain: Knee pain has a wide variety of causes and treatments. Home care for knee pain involves protecting the knee from further trauma, in addition to resting, icing, compressing, and elevating the knee. In order to diagnose knee pain, the physician may need to perform a physical exam, get an X-ray, CT scan, MRI, remove fluid, and/or perform blood tests or arthroscopy. Treatment of knee pain depends upon the cause of the knee pain.