Meniscal Transplants

These articles are for general information only and are not medical advice. Full Disclaimer. All articles compliments of the AAOS

The meniscus (the plural is menisci) is a C-shaped cartilage cushion in the knee joint that helps the joint bear weight, glide and turn. Each knee has two menisci, one on each side, that serve as shock absorbers. An orthopedic surgeon may be able to repair a damaged or torn meniscus. However, a meniscus that is badly damaged or has an extensive tear may have to be removed. Without the menisci, a knee joint can develop persistent pain, swelling and arthritis.

In older patients, a knee joint replacement is an option. But for younger individuals (those under 50 or 55 years old) there is an alternative to replacing the entire joint. It’s called a meniscal transplant and it uses donor tissue to replace the damaged meniscus. This procedure is still relatively uncommon and is not appropriate for all patients. However, patients who qualify can benefit from a meniscal transplant.

Who is eligible for a meniscal transplant?

A meniscal transplant may be recommended for people who meet the following criteria:

• Physically active and relatively young, under age 55
• Missing more than half of the meniscus due to surgery or injury or has a tear that cannot be repaired
• Continues to have activity-related pain in the knee
• Has little or no evidence of arthritis in the knee

Where does the transplanted tissue come from?

As yet, there is no synthetic meniscal tissue. The transplanted tissue comes from human donors. Healthy tissues are frozen and matched by size to the candidate.

 

How safe is the donor tissue?

The safety of donor tissue is strictly monitored by the Food and Drug Administration and the American Association of Tissue Banks. Before the transplant is performed, the donor tissue is tested to make sure it is disease-free. Tissues are tested to ensure that they do not have any traces of infectious diseases such as hepatitis or HIV/AIDS. These tests help reduce the risk of contamination. You’re twice as likely to be struck by lightning (odds: 1 in 800,000) than to develop HIV from a meniscal transplant (odds: 1 in 1.6 million).

 

How is the surgery performed?

A meniscal transplant is an outpatient procedure performed using tiny instruments and a small incision (arthroscopic surgery). A regional anesthetic is used. The surgeon will make one small incision in the knee joint, with two or three other “nicks” to help situate the transplant properly. These secondary incisions are so small that they may not even require sutures to close them. The new meniscal tissue is anchored to the tibia, the larger bone in your lower leg.

 

How long is the recovery period?

For the first three to four weeks after surgery, you will have to use crutches and wear a knee brace or immobilizer. This gives the transplanted tissue time to become firmly attached to the bone. If you work in an office and have a basically sedentary job, you should be able to return to work a week after your surgery. If you have a more active job, you may not be able to resume all your job duties for two to three months.

After a month, you can start an exercise therapy program that involves weight-bearing exercises. In many cases, you may be able to return to running after three or four months, and to other recreational activities after five or six months. You should not do certain kinds of activities, such as squatting, bicycling or swimming, for at least six months after surgery.

 

Are there any complications to the surgery?

With any surgery, there are some risks. However, the risk of complications from meniscal transplants is very slight, less than one percent. The two most common complications are infections and tissue rejection.

 

How successful are meniscal transplants?

Orthopedic specialists have been doing meniscal transplants for several years. In 80 percent to 90 percent of cases, they are effective in relieving activity-related pain and swelling. However, long-term results are not yet available. It’s also not known whether the transplant will delay or slow the development of arthritis or other degenerative changes in the knee.

Meniscal transplants aren’t right for every patient. If you already have arthritis in your knee, a meniscal transplant may not help you. But in a select group of patients, meniscal transplants offer significant benefits.