Meniscus tears are among the most common knee injuries. Athletes, particularly those who play contact sports, are at risk for meniscus tears. However, anyone at any age can tear a meniscus. When people talk about torn cartilage in the knee, they are usually referring to a torn meniscus.
Three bones meet to form your knee joint: your thighbone (femur), shinbone (tibia), and kneecap (patella).
Two wedge-shaped pieces of cartilage act as “shock absorbers” between your thighbone and shinbone. These are called meniscus. They are tough and rubbery to help cushion the joint and keep it stable.
Menisci 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, and radial.
Sports-related meniscus tears often occur along with other knee injuries, such as anterior cruciate ligament tears.
Sudden meniscus tears often happen during sports. Players may squat and twist the knee, causing a tear. Direct contact, like a tackle, is sometimes involved.
Older people are more likely to have degenerative meniscus tears. Cartilage 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.
You might feel a “pop” when you tear a meniscus. Most people can still walk on their injured knee. Many athletes keep playing with a tear. Over 2 to 3 days, your knee will gradually become more stiff and swollen.
The most common symptoms of meniscus tear are:
Without treatment, a piece of meniscus may come loose and drift into the joint. This can cause your knee to slip, pop, or lock.
After discussing your symptoms and medical history, your doctor will examine your knee. He or she will check for tenderness along the joint line where the meniscus sits. This often signals a tear.
One of the main tests for meniscus tears is the McMurray test. Your doctor will bend your knee, then straighten and rotate it. This puts tension on a torn meniscus. If you have a meniscus tear, this movement will cause a clicking sound. Your knee will click each time your doctor does the test.
Because other knee problems cause similar symptoms, your doctor may order imaging tests to help confirm the diagnosis.
X-rays. Although x-rays do not show meniscus tears, they may show other causes of knee pain, such as osteoarthritis.
Magnetic resonance imaging (MRI). This study can create better images of the soft tissues of your knee joint, like a meniscus.