Knee pain is an extremely common complaint in an orthopedic surgeon's office. Some of the questions that we use to help sort out the cause of knee pain include:

• Is this an acute problem, or has is it started slowly without a known injury?
• Is there swelling associated with the pain?
• Is the pain related to certain activities, or does it occur at all/any times, even at night?
• Are there mechanical symptoms of locking, catching, or buckling that are associated with the pain?

Your concern about locking or catching sensations is important, as those can often be signs of a meniscus or cartilage injury. The meniscus is the soft "cushion" in the knee that lies between the joint surfaces. Tears of this structure are common, and there are multiple options for treating this problem that range from simple over-the-counter pain medications and activity modification to surgery, if the symptoms are severe enough.

A good physical exam from your orthopedic surgeon can help to delineate whether the pain and locking sensations are coming from a torn meniscus, or some other structure in the knee. In many cases, an MRI exam is used to visualize these structures, as X-rays can only see the bones of the knee joint.