See a doctor the same day if your knee is hot and red with a fever, you cannot put weight on it, it looks deformed, or your calf is swollen and tender. These can be signs of infection, a fracture or a blood clot.
Book a routine visit if
- Pain lasts more than a few weeks despite home care
- The knee locks, catches or gives way
- Swelling keeps coming back
- Pain wakes you at night
- Pain limits walking, work or sleep
What the doctor may do
- Examine the knee and ask how it started
- X-ray for arthritis or bone problems
- MRI for meniscus, ligament or cartilage problems
- Blood tests or joint fluid test for gout or infection
Already have an MRI? You can have a doctor review it.