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 that slowly tear over time.
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:
- Stiffness and swelling
- Catching or locking of your knee
- The sensation of your knee "giving way"
- You are not able to move your knee through its full range of motion
Without treatment, a piece of meniscus may come loose and drift into the joint. This can cause your knee to slip, pop, or lock.
Your treatment will depend on your age, the type of tear you have, its size, and location.
Most degenerative meniscus tears in older patients respond well to physical therapy. In some patients who fail physical therapy, surgery may be necessary.
Younger patients often tear the meniscus during a sporting event or other athletic activity. Depending on the tear pattern, meniscus tears are repaired in the younger age group. Whether a repair is attempted depends on the location of the tear relative to the blood supply.
The outside one-third of the meniscus has a rich blood supply. A tear in this "red" zone may heal on its own, or can often be repaired with surgery. A longitudinal tear is an example of this kind of tear.
In contrast, the inner two-thirds of the meniscus lacks a blood supply. Without nutrients from blood, tears in this "white" zone cannot heal. Because the pieces cannot grow back together, tears in this zone are usually surgically trimmed away.
If your symptoms persist with nonsurgical treatment, your doctor may suggest arthroscopic surgery.
The surgeon uses a camera to look inside the knee to evaluate the tear. At that time the torn tissue will be excised or repaired based on the surgeon’s evaluation.
If you have had a meniscus repair procedure, you will need to use crutches for about a 6 weeks to allow the repair to heal. There will be a specific physical therapy program aimed at restoring knee function. Rehabilitation time for a meniscus repair is about 3 months.
Patients who have a partial menisectomy return to activities quickly as the damaged tissue is removed. Most patients return to work or sports in 2-3 weeks.