A meniscus tear is damage sustained to the rubbery, disc-shaped "shock absorber" cartilage inside the knee joint. Such injuries are extremely common in people over age 30, especially athletes who play contact sports.
Most of the time, when someone refers to having torn knee cartilage, he or she is referring to a meniscus tear.
What is the meniscus, exactly?
The meniscus is a c-shaped piece of cartilage that functions as padding between the bones of the knee. Each knee has two menisci — a medial meniscus (in the inner side of the knee) and a lateral meniscus (in the outer side of the knee).
The main purpose of the two menisci is to absorb pressure and distribute your body weight through the knees. Menisci also function as another layer of protection for your leg bones, protecting them from osteoarthritis.
Because the knees absorb so much impact from walking, running, and playing sports, the menisci absorb a great deal of impact pressure throughout the day.
Over time and with age, the cartilage naturally begins to wear away from friction, making it more prone to injury. Although anyone at any age can suffer a meniscus tear, people over age 30 are more at risk due to this age-related degeneration.
CAUSES of meniscus tears
Meniscus tears tend to be caused by sudden twisting motions, especially when playing sports.
For example, you might tear your meniscus dodging someone on the basketball court or sliding into a base during a baseball or softball game.
However, people also tear their menisci doing everyday activities:
- climbing and descending stairs or hills
- getting up from a chair awkwardly
- bending the knee too far when squatting or kneeling (called "hyperflexing"), especially when lifting a heavy weight
- walking on an uneven surface (like a poorly paved sidewalk or rough terrain)
You're most at risk if you meet any of the following criteria.
Risk factors for meniscus tears
- You're age 30 or older. (You're more likely to sustain a degenerative tear if you are over 30; however, anyone at any age can tear a meniscus.)
- You participate in a sport that involves pivoting (basketball, golf, tennis).
- You play contact sports where your knee may sustain a blow when your foot is planted (football, hockey, rugby).
- You have a degenerative condition that has already weakened your cartilage, like osteoarthritis.
Being obese also puts added strain on the knee joints, which can contribute to cartilage degeneration at an earlier age.
SYMPTOMS of a meniscus tear
How will you know if you've torn your meniscus? Symptoms may include:
- pain in the knee
- a popping sound or sensation
- the knee buckling or "giving way"
- inability to straighten the knee, due to an increase in fluid around the injury site
- swelling around the joint
- stiffness that increases in the 2–3 days after you sustained your injury
Keep in mind, many meniscus tears are small and may not present as acute injuries. You may still be able to walk on your knee and participate in activities. Instead of being temporarily disabled, you may find that you notice your knee behaving differently over time.
Subtler symptoms of a meniscus tear may appear from time to time. For example, you may experience the following symptoms occasionally:
- buckling or giving way of the knee
- locking — your knee gets stuck in a flexed position and cannot straighten or bend
- popping in the knee, especially when climbing up or down stairs
- knee pain when running or walking long distances
- tightness of the knee joint
MENISCUS injuries: types of tears
Meniscus tears are categorized by orthopedists based on how they look and where they occur within the meniscus.
- Bucket-handle tears. These are round or oval tears within the center part of the cartilage. They get their name because they create holes in the meniscus.
- Flap tears. These are partial tears that create a loose flap of cartilage, oftentimes along the inner edge.
- Radial tears. These horizontal tears tend to be smaller and less ragged than flap tears.
- Degenerative tears. These are ragged and tend to occur in older people with pre-existing degeneration of the cartilage.
How well a meniscus tear heals depends in part on where it occurs. Tears in the blood-rich "red zone" at the outer edge of the meniscus can sometimes heal on their own without medical intervention. Tears along the inner portion, in the "white zone," do not receive as many nutrients and therefore may require immobilization or surgery.
MENISCUS REPAIR treatment and SURGERY
In some cases, you can treat the pain and discomfort of a meniscus tear with RICE therapy (rest, ice, compression, and elevation) or NICE therapy (non-steroidal anti-inflammatory drugs, like ibuprofen or naproxen), ice, compression, and elevation).
However, if you suspect you've injured your meniscus, see an orthopedist.
Many meniscus injuries occur in the inner two-thirds of the meniscus, in the "white" zone where blood supply is not as rich. Without nutrients, these injuries seldom heal on their own.
Left untreated, a damaged meniscus can lead to other problems in your knee. Loose meniscus cartilage may move around inside your joint, leading to locking or popping of the knee and knee instability. A chronically injured meniscus can also lead to arthritis.
After evaluating you, an orthopedist may recommend arthroscopic meniscus repair, meniscectomy (full or partial), or, in the case of severe damage, a total knee replacement surgery.
If you think you have a torn meniscus, give Coastal Orthopedics located in Corpus Christi, TX a call. Our orthopedic specialists can examine you, assess your condition, and discuss whether surgical meniscus repair may be an option for you. Telephone: 361.994.1166.
Article written by: Rob Williams, MD