Ask the Orthopedic Surgeon: What is the meniscus?

Question:
I keep hearing of athletes tearing their meniscus.  What exactly is the meniscus and what does it do and what happens if it is torn?

Answer:  What is the meniscus?
The meniscus is a c-shaped piece of cartilage in the knee that acts as a cushion between thigh bone and shin bone.  The meniscus acts as a shock absorber and keeps the knee stable.  The meniscus also distributes our weight evenly over the knee. The most common causes of a meniscal tear are a sudden twist of the knee or overuse.

What are the symptoms of a torn meniscus?

-  A “pop” may be felt at the time of the injury

-  Pain

-  Stiffness & Swelling

-  Limited range of motion

- “Locking or Catching”

How is a torn meniscus treated?

Treatment of meniscal tears vary depending on the size, severity and location of the tear.  Tears that are small in size and on the outer edge of the meniscus may not require surgery.  In these cases, the protocol is RICE:  Rest, Ice, Compression and Elevation combined with anti-inflammatory medications (aspirin or ibruprofen). The patient may or may not be required to wear a brace.

If the meniscal tear is moderate to severe, a knee arthroscopy is often needed. Knee arthroscopies are performed through a small incision in the knee.  An orthopedic surgeon then inserts a small camera, which provides a clear view of the knee.  From there, the orthopedic surgeon either repairs the tear or removes the torn portion of the menisci.

Depending on the location of the tear, an orthopedic surgeon decides whether to remove or repair a tear.  The outer layer of the meniscus is often referred to as the ‘red zone’ because it has a good blood supply, which is necessary for healing.  The inner layer is sometimes referred to as the ‘white zone’, which lacks a decent blood supply and makes healing difficult.  If the tear is located in the red zone it is normally repaired, but if it is in the white zone, it is normally fully or partially removed.  Full removal is normally avoided, if possible, as it can leave the patient more prone to osteoarthritis in the future.

For a meniscal repair, the recovery time is about 3 months, with 4-6 weeks on crutches and physical therapy.  A partial menisectomy (removal of the meniscus) has a recovery time of about 6 weeks and only 3 days on crutches.  Physical therapy is needed as well.  In both cases, patients are able to return to full activity.