A meniscus tear refers to an injury or damage to the meniscus, a C-shaped piece of cartilage in the knee joint. Each knee has two menisci—one on the inner side (medial meniscus) and one on the outer side (lateral meniscus). The menisci act as shock absorbers and help stabilize the knee by distributing the load across the joint.
Meniscus tears can be painful, making it difficult to work, do household chores, exercise, or simply enjoy your favorite everyday activities. However, you don't have to suffer in silence. The orthopedic surgeons at Northwest Extremity Specialists can evaluate your injury to determine if surgical meniscus repair can help you get back to making the most of each day.
Causes of Meniscus Tears
Meniscus tears commonly occur due to twisting or rotational forces applied to the knee during activities involving sudden stops, pivoting, or changing directions, such as sports or lifting heavy objects. They can also result from degenerative changes in the meniscus due to aging and general wear and tear.
Symptoms of a Meniscus Tear
The symptoms of a meniscus tear can vary depending on the type and location of the tear. However, some of the most common symptoms include:
- Knee pain that is often localized to the inner or outer side of the knee joint
- Swelling and tenderness around the knee
- Difficulty fully straightening or bending the knee
- The sensation of the knee "catching" or "locking" in a certain position
- Popping or clicking sound during knee movement
- Knee instability or a feeling of giving way
- Reduced range of motion in the knee
- Difficulty or discomfort when walking, especially on uneven surfaces
When a meniscus tear is caused by a traumatic event, such as a twisting or pivoting injury, symptoms will occur about 24 hours after the injury. If it's a degenerative meniscus tear, there will be a gradual onset of symptoms.
6 Types of Meniscus Tears
There are six types of meniscus tears: radial, intrasubstance, horizontal, flap, bucket-handle, and complex. The tear is determined with a combination of medical history evaluation, physical examination, and imaging studies.
1. Radial Tears
Radial tears extend from the inner edge of the meniscus toward the outer edge, similar to the spokes on a wheel. Radial tears are the most common type of meniscus tear. These injuries do not heal without treatment because they are in the avascular zone of the meniscus, which does not have a blood supply to provide red blood cells that can repair tissue.
2. Intrasubstance Tears
Intrasubstance tears are sometimes referred to as incomplete tears. They occur within the substance of the meniscus and may not extend to the outer edges. They are a sign of degenerative changes in the meniscus. Intrasubstance tears are considered stable injuries because they do not require surgical treatment. Conservative management with a combination of rest, activity modification, physical therapy exercises to improve knee strength and stability, and nonsteroidal anti-inflammatory drugs (NSAIDs) typically provides the desired pain relief.
3. Horizontal Tears
Horizontal tears occur parallel to the surface of the meniscus and can divide the meniscus into two separate pieces. They are often associated with degenerative changes. The treatment and prognosis for this type of meniscus tear depend on the location of the injury. Tears within the vascular portion can be sewn together by a surgeon instead of needing to remove the damaged portion of the meniscus. However, centrally located horizontal tears can't be repaired and will require that the surgeon remove all or part of the meniscus.
4. Flap Tears
Flap tears create a flap-like structure within the meniscus. The flap can get caught in the knee joint, causing pain, swelling, and locking of the knee. This type of injury is uncommon but can be repaired surgically with minimal tissue removal.
5. Bucket-Handle Tears
Bucket-handle tears are the most serious type of meniscus tear and often occur in conjunction with an anterior cruciate ligament injury (ACL tear). They result in a large, displaced fragment within the knee joint, resembling a bucket handle. Urgent surgical treatment is usually required so that the patient can regain the ability to bend the knee.
6. Complex Tears
Complex meniscus tears involve multiple tear patterns, such as a combination of radial and horizontal tears. They can be more extensive and challenging to repair. The surgeon may attempt to suture the torn edges together, but it may be necessary to trim or remove the damaged portion of the meniscus.