The meniscus is a C-shaped cartilage cushion in the joint of the knee that helps the joint bear weight, glide and turn. Damage to the meniscus, or cartilage, of the knee is very common and affects hundreds of thousands of individuals each year. Injury to the meniscal cartilage usually causes pain and swelling. Weakness or “giving away” of the knee or locking of the joint are common symptoms. The cartilage in the knee is also subjected to stress and movement which, over time, can cause break down leading to arthritis in the area.

When injury to the knee occurs, ideally everything will be done to preserve the meniscal cartilage. There are a variety of techniques available to repair the damaged area including absorbable implants to suture, staple or rivet a tear. In some cases, however, for a meniscus that is badly damaged or has an extensive tear, removal of a portion may be the only option. These patients may be strong candidates for innovative new procedures such as cartilage regeneration or meniscal transplant.

The treatment course will depend upon a multitude of factors including the condition of the ligaments, menisci, cartilage and alignment of the leg. To maintain ultimate stability and alignment, several procedures may be combined to correct all of the problems present.

Debridement or abrasion

The first line of treatment in damage to a meniscus is to attempt repair and conserve as much tissue as possible. Many orthopaedic surgeons choose an arthroscopic technique first for their patients with cartilage injuries. Arthroscopy involves a combination of small incisions, fiber optics and small instruments which are used to allow the surgeon to "clean up" any loose cartilage at the site of the injury. This may include scraping, shaving or vacuuming away frayed or damaged cartilage. The procedure is relatively brief and done on an outpatient basis.

Meniscal Transplant

For patients who must have all or most of the meniscus removed one option for treatment is a meniscal transplant. The transplanted tissue is either synthetically produced, or comes from human donors which is strictly monitored by the Food and Drug Administration and the American Association of Tissue Banks. Transplants are matched by size to the candidate.

Who is a good candidate for a meniscus transplant?

• A young to middle-age patient (20-50 years old)

• Underwent prior menisectomy (removal of meniscus)

• Normal or limited damage to the articular cartilage (bone lining) of the joint

• Symptoms consistent with the absence of a meniscus

Cartilage regeneration

Cartilage regeneration can be accomplished through a new technology called Autologous Chrondrocyte Implantation, or ACI. This procedure uses a patient’s own cartilage cells which are transplanted into the knee and allowed to regenerate as healthy tissue. The process is performed in two phases. The first phase requires an orthopaedic surgeon to remove a tiny biopsy of healthy knee cartilage (about the size of a raisin) from the patient during an arthroscopic out-patient procedure. The sample is sent to a lab where technicians then use this biopsy to grow millions of new cells (chrondrocytes) for that patient over a period of four to five weeks. These cells are then re-implanted into the knee where they regenerate and mature into tissue similar to that of normal hyaline articular cartilage.

Recovery: An individualized rehabilitation program will be developed for each patient based on daily activities, lifestyle and progress. The transplanted tissue will need three to four weeks after surgery to develop. During this period certain types of activities such as squatting, bicycling or swimming will need to be avoided. Within three to four months, patients should be able to return to most activities.

Ideal candidates for cartilage regeneration are:

• Generally under the age of 55

• Has a meniscus tear that cannot be surgically repaired

• Is missing more than one half of the meniscus

• Has activity-related pain in the knee

• Has little or no evidence of arthritis in the knee