Meniscal tears are one of the most common knee injuries. A meniscus tear usually require a small twisting force when loaded. Generally athletes and sportsmen who require twisting movement of the knee during their play are at risk for meniscal tears. But even a house wife can also develop a meniscus tear due to simple reason like slip in bathroom. Actually, anyone at any age can tear a meniscus and he/ she may not remember the exact episode of the injury.
Anatomy of the Meniscus (The Basic Structure of the Meniscus)
There are four bones in the knee joint; the thighbone (femur), the shinbone or leg bone (tibia), the side bone of the leg (fibula) and the kneecap (patella). Two ‘C’ shaped structures acts as "shock absorbers" between the thighbone and the shinbone. These are called meniscus. They are tough and rubbery to help cushion the joint and keep it stable.
Description of Meniscus Tear
Meniscus tear in different ways. Tears are noted by how they look, as well as where the tear occurs in the meniscus. Common tears include bucket handle, flap, radial or complex tear. Some radiologists describe meniscus tear as grade I, II or III type. Sports-related meniscal tears often occur along with other knee injuries, such as anterior cruciate ligament tears.
Causes of Meniscus Tear
Sudden meniscal tears often happen during sports. Players may squat or twist the knee, causing a tear. Even a small twist while playing can cause meniscus tear.
A house hold injury like slip over a water spill or a simple rotating jerk during household work can also damage the meniscus. (Read our Blog- How Roger Federer torn his meniscus)
Meniscus weakens and wears thin over time. Aged, worn tissue is more prone to tears. Just an awkward twist when getting up from a chair may be enough to cause a tear, if the menisci have weakened with age. Such tears in older people are called degenerative meniscus tear.
Symptoms of Meniscus Tear
Patient might feel a "pop" when a meniscus is torn; but it may be a silent event in middle age or elderly. After 2 - 3 days of injury, knee will gradually become stiff and slightly swollen. But gradually pain and swelling subsides making patient think that his problem is resolved. Most people can still walk on their injured knee. Many athletes keep playing with a tear. This period of less symptoms or no symptoms is ‘a window period of silence’. This window period is a mis-guiding as it silently causes more damage inside the knee joint until symptoms become apparent again and more severe.
The most common symptoms of a meniscal tear are:
- Pain
- Stiffness and swelling
- Catching or locking of your knee
- The "giving way” sensation at the knee
- Locking of the knee or not able to move knee through its full range of motion
Medical Advise
A general practitioner is usually not trained to diagnose meniscus injury, so are the fracture surgeons. The best doctor to diagnose meniscus injury is an orthopaedic surgeon who has special interest in knee injuries or sports injury or an arthroscopy surgeon.
A well trained doctor can easily suspect meniscus injury on your history. A clinical examination further confirms the diagnosis. The usual examination findings are tenderness on your knee joint line. A clinical test called McMurray test is usually confirmatory.
X-ray are always normal in meniscus tear because meniscus are not seen on x-rays. Still it is always advisable to take x-rays to rule out other associated causes of knee pain.
Magnetic resonance imaging (MRI) is the final test to confirm a meniscus tear, its location, type of tear and plan the definitive treatment for the meniscus tear. Click here to know more about treatment of meniscus tear.