Like a lot of knee injuries, a meniscus tear can be painful and debilitating. Unfortunately, it’s quite common. In fact, a meniscal tear is one of the most frequently occurring cartilage injuries of the knee.
So what is the meniscus? It’s a piece of cartilage in your knee that cushions and stabilizes the joint. It protects the bones from wear and tear. But all it takes is a good twist of the knee to tear the meniscus. In some cases, a piece of the shredded cartilage breaks loose and catches in the knee joint, causing it to lock up.
Three bones meet to form your knee joint: your thighbone (femur), shinbone (tibia), and kneecap (patella).
Two wedge-shaped pieces of fibrocartilage act as “shock absorbers” between your thighbone and shinbone. These are the menisci. The menisci help to transmit weight from one bone to another and play an important role in knee stability.
A meniscus tear is a common knee injury. The meniscus is a rubbery, C-shaped disk that acts as a “shock absorber” between the thighbone and shinbone. It helps cushion and stabilize the knee joint. Each knee has two menisci—one on the outside of the knee and one on the inside.
A meniscus tear is often caused by a single acute injury—such as a sudden twist or quick turn during sports activity. Because the menisci weaken and wear thin over time, older people are more likely to experience a degenerative meniscus tear.
In many cases, a surgical procedure called “arthroscopy” is used to repair or remove a torn meniscus.
What is a Medial Meniscus Tear?
The quick answer is the menisci— the medial meniscus and lateral meniscus- are crescent-shaped bands of thick, rubbery cartilage attached to the shinbone (tibia). They act as the major shock absorbers of the knee. The medial meniscus is located on the inside part of the knee joint. They are sometimes called “meniscuses” but the correct plural spelling is menisci.
The lateral meniscus is located on the outside part of the knee. Meniscus tears can vary widely in size and severity. A meniscus can be split in half, ripped around its circumference in the shape of a C, or left hanging by a thread to the knee joint.
The quick answer is that a meniscus tear can occur when the knee is suddenly twisted while the foot is planted. Such has a quick pivot on a basketball court or taking a hard tackle while the leg is planted can cause a meniscus tear. Moving forward, we will be discussing the medial meniscus tear. If you would like to learn more about the knee’s anatomy, please go to KNEE Anatomy.
What Are The Symptoms Of A Meniscus Tear?
Very often, meniscal tears do not cause symptoms or problems. However, some people with a torn meniscus know exactly when they hurt their knees. There may be the acute onset of knee pain and the patient may actually hear or feel a pop in their knee. As with any injury, there is an inflammatory response, including pain and swelling.
The swelling within the knee joint from a torn meniscus usually takes a few hours to develop and depending upon the amount of pain and fluid accumulation, the knee may become difficult to move. When fluid accumulates within the enclosed area of the knee joint, it may be difficult and painful to fully extend or straighten the knee, since the knee has the most space available when it is about 15 degrees flexed.
In some situations, the amount of swelling may not necessarily be enough to notice. Sometimes, the patient isn’t aware of the initial injury but starts noting symptoms that develop later. Moreover, there may not be an acute injury. The knee cartilage may become damaged as a consequence of aging, arthritis, and wearing away of the meniscus causing a degenerative meniscal tear.
After the injury, the knee joint irritation may gradually settle down and feel relatively normal as the initial inflammatory response resolves. However, other symptoms may develop over time and may include any or all of the following:
- Pain with running or walking longer distances
- Intermittent swelling of the knee joint: Many times, the knee with a torn meniscus feels “tight.”
- Popping, especially when climbing up or downstairs
- Giving way or buckling (the sensation that the knee is unstable and the feeling that the knee will give way): Less commonly, the knee actually will give way and cause the patient to fall.
- Locking (a mechanical block where the knee cannot be fully extended or straightened): This occurs when a piece of torn meniscus folds on itself and blocks the full range of motion of the knee joint. The knee gets “stuck,” usually flexed between 15 and 30 degrees, and cannot bend or straighten from that position.
6 Types of Meniscus Tears
Meniscus tears are a common cause of knee pain and many people end up with arthroscopic knee surgery for their condition. But is surgery always necessary? Are all meniscus tears treated the same?
In practice, a variety of factors are used to determine the ideal treatment of a meniscus tear. Some of these factors include the age of the patient, results of nonsurgical treatment, and if there is other damage than just a torn meniscus.
In addition, the specific type of meniscus tear can determine the most appropriate treatment. Described here are six common types of meniscus tears.
- Intrasubstance/Incomplete Tear: An intrasubstance tear is a common finding on an MRI report. Seen in the upper left corner of the image, an intrasubstance tear typically looks normal at the time of surgery. Often these are a sign of early degenerative changes of the meniscus tissue, but seldom are they the sign of a problem. Incomplete and intrasubstance tears of the meniscus are stable injuries, and they generally do not require any surgical treatment. By the time people are in their 20s or 30s, intrasubstance changes of the meniscus tissue are very commonly seen on an MRI.
- Radial Tear: Radial tears of the meniscus, pictured in the middle of the top row on the image, are the most common type of meniscus tear. These tears are within the avascular zone of the meniscus, where there is no blood supply, and therefore there is little capacity for these tears to heal. Therefore, when these tears come to requiring surgical treatment, typically the only option is to trim out the damaged portion of the meniscus.
- Horizontal Tear: A horizontal tear is a tear that is most commonly amenable to meniscus repair.3 Seen in the upper right corner of the image, a horizontal tear runs along the circumferential fibers of the meniscus. Rather than removing the damaged portion of the meniscus, a horizontal tear may be able to be sewn together. The key to determining the treatment of these tears is their location. If located within the vascular portion of the meniscus (near the outer edge) then there is healing potential, and thus repair. When located more centrally, these tears will not heal, even if repaired.
- Flap Tear: A flap tear of the meniscus, pictured in the bottom right corner of the image, is an unusual pattern of the tear. In circumstances where the flap is causing symptoms of catching in the knee, usually, the flap of the meniscus can simply be removed without removing much tissue at all.
- Complex Tear: A complex tear means there is a combination of tear patterns. Shown in the middle image on the bottom row, a complex tear often involves both radial and horizontal tear patterns. Typically complex tears are not treated with meniscus repair because of the complex nature of the tear. In some unusual circumstances, some of the torn meniscus can be removed, while other portions can be repaired.
- Bucket-Handle Tear: A bucket-handle tear is a large type of horizontal tear of the meniscus. These tears often cause the knee to become stuck by causing the torn portion of the meniscus to block normal knee motion. Bucket-handle tears often require more urgent surgical treatment in order to allow the knee to start bending again.
Causes of a Meniscus Tear
The meniscus can be torn during activities that cause direct contact or pressure from a forced twist or rotation. A sudden pivot or turn, deep squatting, or heavy lifting can lead to injury. Many athletes are at risk for a meniscus tear.
Sports that require sudden turns and stops may put you at higher risk for meniscus tears. Some of these sports include:
- football
- basketball
- soccer
- tennis
According to Boston Children’s Hospital, meniscus tears are growing increasingly common in children. This is because children are participating in organized sports at an earlier age. Additionally, when focusing on just one sport, a child is more likely to experience a meniscus tear. The same is true for adolescents who participate in competitive sports.
The meniscus weakens with age. Tears are more common in people over the age of 30. Movements like squatting or stepping can lead to injury in someone with weak menisci.
If you have osteoarthritis, you’re at higher risk of injuring your knee or tearing your meniscus. Osteoarthritis is a common joint disorder involving pain and stiffness in your joints caused by aging and wear and tear.
When an older person experiences a meniscus tear, it’s more likely to be related to degeneration. This is when the cartilage in the knee becomes weaker and thinner. As a result, it’s more prone to tear.
How Is a Meniscus Tear Diagnosed?
If a meniscal tear is suspected, your orthopedist will conduct a thorough health history and evaluation of the knee and may also order X-rays and magnetic resonance imaging (MRI) to confirm the diagnosis and further evaluate the knee joint:
X-ray
An X-ray is a diagnostic test that uses invisible electromagnetic energy beams to produce images of internal tissues, bones, and organs onto film. When a standard X-ray is not accurate enough, a joint X-ray with contrast dye may also be used to examine joints such as the knee or hip.
MRI
An MRI is a diagnostic procedure that uses a combination of large magnets, radiofrequencies, and a computer to produce detailed images of organs and structures within the body; can often determine damage or disease in a surrounding ligament or muscle.
Treatment for Meniscus Tears
If you have symptoms of a meniscus tear, it probably won’t heal by itself and you’ll need some form of treatment. You’ll usually need to go to A&E with this kind of injury, where they’ll examine you and take some X-rays of your knee. You may then be referred to an acute knee clinic, which will organise any investigations and treatment you need.
What treatment you’re offered will depend on exactly where the meniscus tear is, how big it is, how severe your injury is and your age. The initial treatment will be to control your pain and swelling using the POLICE and HARM self-help measures (see above). Further treatments for meniscus tears include physiotherapy, medicines and surgery.
You may see a physiotherapist or an orthopaedic surgeon (a doctor who specialises in bone surgery) for treatment.
Medicines for meniscus tears
You can take over-the-counter painkillers, such as paracetamol or ibuprofen, to help relieve any pain from a meniscus tear. Your doctor may prescribe stronger painkillers if your pain is really bad. As well as easing your pain, non-steroidal anti-inflammatory drugs (NSAIDs) such as ibuprofen may help to reduce inflammation and swelling. Always read the patient information that comes with your medicine, and if you have questions, ask your pharmacist or GP for advice.
Physiotherapy for meniscus tears
Your physiotherapist will carefully assess your knee and they will then plan an individual programme of rehabilitation exercises. These will be designed to help strengthen your knee and leg muscles gradually. This should help your knee recover its full range of movement, as well as its strength and stability. Make sure you do the exercises as this is an important part of your recovery from a meniscus tear.
Surgery for meniscus tears
If you have a large meniscus tear, or you’ve tried physiotherapy on its own for at least three months and it hasn’t helped, you may need to have an operation to repair it. Surgery may involve either repairing your torn meniscus, or removing the damaged part of your meniscus. Your surgeon will usually do the operation in a knee arthroscopy, which is a type of keyhole surgery. You’ll need to have physiotherapy afterwards to get your knee back to normal, and working as it should.
Ask your doctor about the pros and cons of surgery, and how it might help you.
Is It Possible to Prevent a Torn Meniscus
Meniscus tears are tough to prevent since they’re usually the result of an accident. But some precautions might lower the risks of a knee injury. You should:
- Keep your thigh muscles strong with regular exercises.
- Warm up with light activities before taking part
- Give your body time to rest between workouts. Fatigued muscles can increase your risk of injury.
- Make sure your shoes have enough support and fit correctly.
- Maintain flexibility.
- Never abruptly increase the intensity of your workout. Make changes slowly.
Once the cartilage is damaged, it cannot be repaired to be as good as the original. For that reason, prevention may actually be the best treatment for a torn meniscus. A lifelong commitment to maintaining a healthy weight and avoiding injury will decrease the stress placed on the cartilage of the knee during daily activities. Keeping muscles strong and flexible will also help protect joints. For the knee, this includes not only the quadriceps and hamstring muscles but also those in the core and back.
