The knee joint is one of the largest in the body, rivaling others in complexity and importance. Since it is so vital to movement, it is quite easy to injure the knee through simple actions or athletic endeavors. Part of the reason it can sustain so many problems is because it is comprised of many different, interlinking parts. This allows for many problems to occur.
Of the types of knee injuries, tears of the meniscus are quite common. In fact, contact sport athletes are particularly at risk for a tear of this cushioning cartilage. You don’t need to be an athlete, though, to tear this tissue, and any age group is susceptible. A torn meniscus is often called torn cartilage in the knee, and they are the same thing.
The knee joint is made up of the meeting of three important bones. The thigh bone, or femur, makes up the top half of the knee joint, while the shin bone, or tibia, makes up the lower part of the structure. In the center of the meeting is the kneecap, or patella, that slides across the top of the joint.
The meniscus is located between the femur and the tibia. In fact, you have two in each knee, one on each side, that form wedge-shaped pieces. These cartilage pads are used as shock absorbers between the joining bones. Their tough, rubbery material makes them perfect for protecting the ends of the bones and supporting the weight of the body.
Either of the menisci can tear in different ways. Most tears are named after how they appear, but some are named for where in the meniscus the tear occurs. It is possible to have longitudinal tears in the cartilage, a parrot-beak presentation, a simple flap, or a bucket handle appearance. Of course, many tears are complex and are not easily categorized.
Unfortunately, when the meniscus is torn as part of a sports injury, it usually occurs with other knee problems, such as anterior cruciate ligament tears.
When an athlete squats or twists the knee, meniscal tears often occur. Of course, direct trauma, as from a tackle or impact, can also cause the cartilage to tear in addition to other injuries.
Due to the process of aging, the meniscus can degenerate and lead to tears in the tissue. Old age causes the cartilage to weaken and become thinner as the years pass. This wearing out can make the tissue more likely to tear, and even just awkward movements, such as twisting when rising from a chair, is enough to cause a tear.
Some patients experience a popping sensation when the meniscus tears, but it often doesn’t impair the ability to walk. In fact, some athletes can continue playing with a torn meniscus, but stiffness and swelling will appear after two to three days following the injury.
Meniscal tears have many common symptoms:
Your knee “giving out”
Inability to move the knee through its normal range of motion
Unfortunately, failure to treat a torn meniscus can cause the ragged piece to become loose. They drift into the joint, causing knee slippage, popping, or locking out of the joint.
Examination and History
The exam will start with a discussion of your medical history and the symptoms that prompted you to seek treatment. An examination will follow in which your orthopedist will feel for tenderness along the line of the joint, or the anatomical position of the meniscus. Pain in this region could signal a tear.
In addition, your doctor can perform a McMurray test. You will bend your knee, then your doctor will straighten and rotate it. By performing this action, the tension increases on the meniscus. With tears, this test will elicit a clicking sound every time the movement is performed.
Not all knee problems can be accurately assessed through examination alone, and this means that imaging tests may be necessary to definitively diagnose a tear.
X-rays are useful, but not because they show meniscal tears. They can illuminate other reasons for knee pain, such as osteoarthritis and other joint issues.
The definitive test for meniscal tears is magnetic resonance imagining, or MRI. This test specializes in visualization of the soft tissue of the joint and can better outline a problem with the meniscus.
Treatment for meniscal tears depend on the type you have, the size of the injury, and the location in the cartilage tissue.
Fortunately, the outer third of the meniscus has a great supply of blood, known as the red zone. Tears in this area usually heal on their own without surgery. For instance, a longitudinal tear is very likely to heal on its own for this reason.
The inner two thirds of the cartilage do not have as ample a blood supply, and the lack of nutrients from blood in this white zone means the tissue doesn’t heal as readily. In addition, tears in this area are often complex, caused by thin, worn cartilage. When it is unlikely that the pieces will heal together, tears are generally trimmed away in a surgical procedure.
Your orthopedic surgeon will also consider the type of tear you have, your level of activity, and any other injuries that may have occurred to your knee in the process of the meniscus tear.
Small tears in the red zone are more likely to respond to nonsurgical treatment. However if symptoms persist or the knee is unstable, surgical intervention may be necessary.
Most meniscal tears respond to the RICE protocol, which stands for rest, ice, compression, and elevation.
Rest means simply to stop performing the activity that caused your injury. In addition, you should avoid putting weight on the leg.
Ice is helpful in reducing swelling. You can place cold packs on your knee for 20 minutes at a time, separated by 40 minute rest periods. You should also avoid applying the ice directly to the skin.
Compression is where elastic bandages come into play. They compress the area and reduce swelling and pain that is caused by the inflammation of the injury.
Elevation is a technique by with you use gravity to decrease swelling. Placing your leg on an incline that brings it above the level of the heart will help to decrease pain.
Non-steroidal anti-inflammatory drugs that can be purchased over the counter, such as aspirin and ibuprofen, can also help reduce swelling and pain.
If you still have pain despite nonsurgical treatment or the tear is in the white zone, you may be a candidate for arthroscopic surgery.
This type of surgery is among the most commonly performed procedures. Through a small incision, the surgeon will insert a miniature camera that gives a clear view of the inside of the knee. Through another incision, the surgical instruments will be inserted and manipulate the tissue. In the case of meniscus tears, this usually involves surgical scissors to remove the torn component.
Following surgery, you will need rehabilitation to regain the normal use of your knee. In the early stages, you may need a cast or brace to keep the joint immobilized so it can heal.
After the immediate post-operative phase, you will need to do exercises to regain the use of the joint. This will help to improve the mobility of the knee and rebuild the strength in the tissue. Most exercises in the beginning will focus on improving your range of motion and strengthening exercises will be added in at a later time.
Most of these exercises can be performed at home, but some severe or complex tears may require that you meet with a physical therapist every week.
A tear in the meniscus is extremely common, and most patients find that they can return to their pre-injury activities. With proper diagnosis, treatment, and rehabilitation, patients recover from meniscal tears with very few complications.