Knee pain has numerous different potential causes that include both pathology within the knee joint and pathology that presents with pain referred into the knee and felt in and around the knee joint. Examples of this include hip pain, lower back pain, and less commonly, pelvic pain.
Causes from within the knee joint include arthritis, meniscal tears, osteochondral defects, osteonecrosis, patella maltracking, patellofemoral syndrome, cruciate ligament damage, collateral ligament damage, and other more rare causes such as pigmented villonodular synovitis (PVNS).
Any persistent knee pain that has proven unresponsive to over-the-counter analgesia, exercise, rest or sustained physical activity should be referred to a specialist physician or orthopaedic surgeon. They will be begin by discussing your medical history with you and performing a physical examination. The discussion will include questions about the knee pain and its duration, nature, characteristics and exacerbating or alleviating factors.
The physical examination of the knee joint will involve feeling your knee joint and moving it around, as well as performing certain special tests designed to detect abnormalities in certain structures within the knee. You may be asked to undergo plain film radiographs – x-ray studies that will give us more information about the anatomy of your knee and potentially give us a diagnosis. If at this point the diagnosis is still unclear, then further imaging studies such as a CT or MRI scan may be ordered in order to achieve a definitive diagnosis.
The first line treatment for any joint pain should be rest of the affected joint for a short period of time. Over-the-counter analgesics such as Tylenol or nonsteroidal anti-inflammatory medications are also appropriate. If neither of these prove effective at relieving your pain then you may require a full course of dedicated physical therapy. If this also proves ineffective then consultation with a healthcare professional in regards to your knee pain is warranted.
Definitive and effective treatment of persistent knee pain requires a firm diagnosis, and depending on what your diagnosis is, the treatment may be simple and involve a prolonged period of activity modification, or it may be more serious and require a surgical procedure to correct. It is also important to recognize when consultation with a specialist physician is necessary – avoiding seeing a doctor with a diagnosis such as an ACL rupture, for example, can lead to more serious problems developing earlier on in life.
Untreated ACL-deficient knees will lead to a phenomenon known as repeated tibiofemoral subluxation (abnormal movement of the two bones within the knee relative to one another) and this will lead to rapid wear of the joint cartilage and development of potentially debilitating arthritis much earlier on in life than if the problem had been treated with an ACL Reconstruction, or even an ACL-specific brace.
Knee pain has a potentially wide range of causes – some are less serious and self-limiting, others will require medical or surgical intervention to treat effectively. It is important to identify persistent troublesome knee pain early on and seek out medical attention for it as early as possible to avoid a potentially very easily treatable condition being left untreated and developing into a more serious problem which requires more invasive treatment.