A meniscus tear is a common injury to the cartilage that stabilizes and cushions the knee joint. The pattern of the tear can determine whether your tear can be repaired. See a picture of different types of tears. Radial tears sometimes can be repaired, depending on where they are located. Horizontal, flap, long-standing, and degenerative tears—those caused by years of wear and tear—generally cannot be repaired.
The location (zone) of the tear is one of the most important factors in determining treatment. See a picture of the meniscus zones.
- Tears at the outer edge of the meniscus (red zone) tend to heal well because there is good blood supply. Minor tears may heal with a brace and a period of rest. If they do not heal or if repair is deemed necessary, the tear can be sewn together using dissolvable stitches. This is successful 90% to 95% of the time in this outer edge area.1
- The inner two-thirds (white zone) of the meniscus does not have a good blood supply and so does not heal well either with rest or after repair. If torn pieces float into the joint space, which may result in a "locked" knee or cause other symptoms, the torn portion is removed (partial meniscectomy), and the edges of the remaining meniscus are shaved to make the meniscus smooth.
- When the tear extends from the red zone into the white zone, there may be enough blood supply for healing. The tear may be repaired or removed. This is something the orthopedic surgeon decides during the surgery.
Surgical repair may be done by open surgery, in which a small incision is made and the knee is opened up so that the surgeon can see inside the knee and the meniscus can be repaired. Increasingly, surgeons use arthroscopic surgery to repair the meniscus. The surgeon inserts a thin tube (arthroscope) containing a camera and a light through small incisions near the knee and is able to see inside the knee without making a large incision. Surgical instruments can be inserted through other small incisions. The surgeon repairs the meniscus using dissolvable sutures (stitches) or anchors.
Other knee injuries—most commonly to the anterior cruciate ligament (ACL)—may occur at the same time as a torn meniscus. In these cases, the treatment plan is altered. Typically, your orthopedist will repair your torn meniscus, if needed, at the same time ACL surgery is done. In this case, the ACL rehabilitation plan is followed. For more information, see the topic Anterior Cruciate Ligament (ACL) Injuries.
What To Expect After Surgery
Your surgeon may recommend that you do not move your knee more than absolutely necessary (immobilization) for 2 weeks after surgery. This may be followed by 2 weeks of limited motion before you are able to resume daily activities. Physical therapy should begin right after surgery. But heavy stresses, such as running and squats, should be postponed for some months. You must follow your doctor's rehabilitation plan for optimum healing. Afterwards, you may still continue to have pain and require more physical therapy or, sometimes, additional surgery.
The timetable for returning to walking, driving, and more vigorous activities will depend on your success in rehabilitation. For some exercises you can do at home (with your doctor's approval), see:
Why It Is Done
How your doctor treats your meniscus tear depends upon the size and location of the tear, your age, your health and activity level, and when the injury occurred. Treatment options include nonsurgical treatment with rest, ice, compression, elevation, and physical therapy; surgical repair; surgical removal of the torn section (partial meniscectomy); and surgical removal of the entire meniscus (total meniscectomy). In general, surgical repair is favored over partial or total meniscectomy. If the meniscus can be repaired successfully, saving the injured meniscus by doing a meniscal repair—rather than partial or total removal—reduces the occurrence of knee joint degeneration.
Small tears located at the outer edge of the meniscus often heal on their own. Larger tears located toward the center of the meniscus may not heal well because blood supply to that area is poor. In a young person, surgery to repair the tear may be the first choice because it may restore function. See a picture of common meniscus tears.
How Well It Works
Surgical repair may result in less pain and a return to normal knee function. Also, you may be able to prevent long-term complications (such as osteoarthritis) with successful surgical repair of your tear. The success rate of repair in the red zone is 90% to 95%.1
Successful repair of meniscus tears depends to a large degree upon where the tear is located. Tears at the outer edge of the meniscus (the red zone) tend to heal well. Blood supply to tears that extend into the center of the meniscus (white zone) is questionable, and surgical repair of a tear in this zone may not heal well.
Risks of the surgery itself are uncommon but may include:
- Damage to nerves or blood vessels around the knee.
- Blood clots in the leg.
- Risks due to anesthesia.
What To Think About
If surgical meniscus repair is indicated, the procedure should be performed as soon as possible after the injury. But if the tear is in the red zone and you choose to put off a surgery to see if the meniscus tear heals on its own, a later repair should still heal the meniscus properly.
You may be able to prevent long-term complications such as osteoarthritis with successful surgical repair of your tear. Although no long-term studies have proved this, successful meniscus repair may save meniscal cartilage and reduce the stress put on the knee joint, thereby lowering the risk of osteoarthritis.
Last Updated: September 22, 2008
Author: Shannon Erstad, MBA/MPH