A meniscus is a c-shaped cartilage pad in your knee joint. Each knee has two menisci—one at the outer edge and one at the inner edge. Meniscus tears are a common knee injury that often happen during sports or exercise when there is forceful twisting or turning of the knee joint. Here are the most frequently asked questions about meniscus tears.
What is a meniscus tear?
A meniscus tear refers to damage or injury to one or both of the menisci in your knee joint. The menisci act as shock absorbers between your thigh and shin bones. A tear in the meniscus causes pain, swelling and instability in the knee. Meniscus tears are categorized based on size and location:
•Minor tears: Very small tears located at the outer edge of the meniscus. Minor tears typically heal on their own with rest and physical therapy.
•Bucket handle tears: Longitudinal tears that detach a piece of cartilage that can move into the joint space. Requires arthroscopic surgery to trim or repair.
•Radial tears: Jagged tears that extend from the soft center into the outer rim of cartilage. Usually treated with meniscectomy or meniscus repair surgery.
What causes a meniscus tear?
The most common causes of meniscus tears include:
•Sudden twisting or pivoting motions during sports or exercise that put extreme tension or force on the knee
•Squatting or lifting with heavy loads that also transmit a large amount of stress to the knee
•Age-related degeneration: As we age, the menisci become more prone to tears from small injuries or impacts during normal activity. Degenerative tears are very common over age 65.
•Traumatic injury: Severe injuries like a direct blow to the knee during a fall or collision can cause an acute meniscus tear.
What are the symptoms of a meniscus tear?
The most common symptoms of a meniscus tear include:
•Pain and tenderness: Usually felt along the joint line where the meniscus is located. Pain is often worse with deep knee bending or twisting.
•Swelling: Fluid building up in the knee joint caused by inflammation and irritation. May feel like your knee is “locking up”.
•Limited range of motion: Difficulty fully bending or straightening the knee due to pain and swelling.
•Sensation of instability: Feeling like your knee is giving out or not stable during walking or exercise.
•Clicking or popping: Some people report hearing an audible click when the meniscus tear occurs. A clicking or popping sensation with certain knee movements can also occur.
How are meniscus tears diagnosed?
Meniscus tears are often diagnosed based on symptoms and physical examination. Your doctor will check for tenderness over the meniscus, pain bending/straightening the knee, swelling, and instability. Imaging tests such as:
•MRI: Magnetic resonance imaging is very accurate for detecting meniscus tears. It can determine the size, location and severity of a tear.
•X-rays: Plain X-rays do not show the menisci directly but can rule out other causes of knee pain such as arthritis. They may show fluid in the joint space indicating a torn meniscus.
What are the treatment options for a meniscus tear?
Treatment options for a meniscus tear typically include:
•Rest, ice, compression and elevation: For minor or small tears with minimal symptoms. Activity modification, bracing and physical therapy are also used. Most minor tears will heal within 6 weeks.
•Physical therapy: Exercises to improve strength, flexibility and balance. Can be effective for many type of tears, especially in older patients or those wanting to avoid surgery.
•Surgery- Partial meniscectomy: Removal of the torn and damaged portion of meniscus. Done via arthroscopy. Recovery is typically quick but long term arthritis may develop early.
•Surgery- Meniscus repair: Connecting the torn meniscus with stitches and anchors. Only possible if the tear is in a vascular portion of the meniscus. Recovery is long but preserves meniscus function.
•Surgery- Meniscus replacement/transplant: For severe tears or where most/all of the meniscus is missing or damaged. Uses donor meniscus tissue to replace the native meniscus. A newer procedure with good outcomes so far but still being studied.
The best course of treatment depends on factors such as: the size and severity of your meniscus tear, your age, level of activity, knee stability, and other joint conditions like arthritis. Your doctor can determine the best options based on your unique situation. Surgery may be recommended if other treatments have failed or if the tear is large enough to cause significant pain, swelling or knee locking.
In summary, meniscus tears are a common knee injury that often occur during sports or exercise. Most tears cause pain, swelling and instability in the knee joint. Minor tears may heal with conservative treatment while large tears frequently require arthroscopic surgery to repair or remove the damaged meniscus and allow return to normal function. See your orthopedic doctor right away for an accurate diagnosis and to explore all options for managing your knee meniscus symptoms.