What is Meniscal Transplant and When is it Done? | Procedure, Benefits, Complications of Meniscus Transplant

A surgery done to replace the missing or damaged meniscus is known as meniscus transplantation. The meniscus is a cartilage, which is shaped like C present in pairs in both the kness and is rubbery in nature, which helps in shock absorption to protect the knee joint and the bones of the legs when you move or participate in other activities.^{(1, 3, 4)} Recovery time from a meniscus transplant surgery is around a month; however, rest from rigorous activities and sports for at least a year is needed to heal the knee completely.

A meniscus transplant or meniscus replacement is sometimes also referred to as meniscal allograft transplantation where the allograft tissue is taken from a human donor (cadaver).^{(1, 2)} Studies are ongoing regarding the use of a prosthetic meniscus.

A meniscal transplant is done to replace the damaged cartilage, to provide relief to knee pain and also improve the functioning of the knee. A meniscal transplant or replacement surgery also helps in prevention of development of early osteoarthritis.⁽²⁾

The recovery time from a meniscus transplant surgery is about one to two months to allow the knee sufficient time to heal. The patient needs to take a break from sports and such activities for at least a year.

Not everyone is a right candidate for meniscus replacement/transplant. There are many factors which determine if the patient qualifies for this procedure, such as:

• Overall Health, Activity Level and Age of the Patient: Meniscus transplantation is usually done on active people who are below the age of 40 or 50 and do not suffer from knee arthritis.^{(1, 2)} Adolescents can have this surgery; however, it is recommended to wait till the complete growth of the bones is achieved. The success of a meniscus transplantation surgery is more in individuals who maintain a healthy weight and are physically active.
• Arthritis: Patients suffering from arthritis cannot undergo a meniscus transplant because the knee cartilage has already worn away excessively and the procedure will not be successful.⁽¹⁾
• Knee Anatomy of the Patient: The primary criteria to be eligible for a meniscus replacement or transplant surgery is having an acute meniscus tear or having a missing part of the meniscus with no damage to other areas of the knee. The doctor will assess the proper stability and alignment of the ligaments of the knee before deciding on the surgery.^{(1, 2)}

Teenagers commonly suffer from knee injuries, especially when playing sports. The meniscus tears commonly occur with a sudden twisting motion of the knee.⁽⁴⁾ In case of severe damage to the meniscus, your doctor will advise on removal of the torn meniscus and transplanting it with a healthy one.

Meniscus transplant or replacement is recommended if there is acute damage to the meniscus or if meniscectomy has already been performed due to a previous injury.⁽⁴⁾ Meniscus transplant is also suggested if the damage to the meniscus is very severe, so much so that it cannot be repaired. Living without a meniscus increases the risk of chronic knee pain and osteoarthritis.

If the meniscus is injured or torn, then it can result in osteoarthritis, which occurs when there is severe deterioration of the knee cartilage resulting in stiffness and pain.

Doing a meniscal transplant surgery helps in delaying or preventing the development of osteoarthritis. However, this surgery will not be beneficial for those patients with existing arthritis knee pain.⁽⁴⁾

For a meniscus transplant surgery, the surgeons use a meniscus from a cadaver (human donor). After extracting the meniscus from the donor, it is kept in the freezer to preserve it. Before the surgery the donor meniscus is also tested for any disease and assessed for the shape and size to choose a meniscus, which properly fits into the knee.⁽¹⁾ Preparation of meniscus transplant surgery consists of:

• Imaging studies, such as x-ray or an MRI scan is done to better visualize the internal structures of the knee.⁽⁴⁾
• The doctor asks the patient about any medications which they are taking as certain medications need to be stopped before the surgery.⁽⁴⁾
• The patient will be advised about the time to stop drinking and eating before the procedure.⁽⁴⁾

Knee arthroscopy is a commonly used procedure when doing a meniscus transplant surgery.⁽¹⁾ A tiny camera is inserted via a small incision and through this camera the surgeon can see images from the inside of the knee on a screen.⁽⁴⁾ These images guide the surgeon when inserting small tools via another incision. Any remaining part of the damaged meniscus is removed and replaced with a healthy meniscus in the knee. Screws or sutures are used to attach the meniscus to the knee joint capsule and shinbone.⁽⁴⁾ The incisions are then closed with sutures and a bandage is used to wrap the knee.

Your surgeon will let you know when you can go home and how to take care of your incision. The patient can be allowed to go home the same day of the surgery or may need to stay in the hospital for some time.⁽⁴⁾ Crutches are required for mobility during the recovery period.⁽⁴⁾ Brace is also used to stabilize the knee and in preventing undue movement. The recovery period post meniscus replacement surgery also consists of rest and physical therapy along with special stretches and exercises to strengthen the muscles surrounding the knee and improving the range of motion of the knee.

A meniscus transplant surgery is a minimally invasive procedure; hence, it needs less recovery period when compared to the traditional open surgery. Doing a meniscus transplant surgery helps in younger adults who are physically active to enjoy sports and to get back to their old activities without any pain and enables them to continue performing and enjoying them. A meniscus transplant surgery also benefits by preventing development of early osteoarthritis due to the damaged meniscus.

Developing complications from a meniscus replacement surgery is very rare.⁽¹⁾ The risks are same as with any surgery, such as infection and bleeding. After the surgery some patients can develop:^{(1, 4)}

• Knee stiffness.
• Damage to soft tissues, nerves and blood vessels of the knee.
• Difficulty with healing needing second surgery.

The prognosis differs and depends on various factors, such as:

• The shape, size and placement of the transplanted meniscus.
• The general health of the patient; the condition of your knee and the alignment of the knee ligaments.
• Patient’s commitment to a physical therapy program after the surgery.

Sometimes patients can tear the new meniscus resulting in a need of another surgery. This secondary surgery commonly consists of debridement where the damaged or torn cartilage is removed.

You doctor is the best person to guide you regarding the period of time where you need absolute rest and when you can start mild activities before commencing full fledged regular activities including sports. Many patients are advised a complete rest for at least a couple of weeks post meniscus transplant surgery. A year of compete break from sports and other exerting activities is needed to allow your knee ample time to heal.⁽¹⁾

Contact your doctor immediately if you are having persistent pain, which does not go away even with pain killers; if you are having bleeding and experiencing signs of infection, such as fever, acute swelling or pus drainage from the incisions.⁽⁴⁾

Meniscus transplant surgery benefits people who are active in their lives without having to experience any knee pain along with preventing the development of osteoarthritis. Not everyone is a suitable candidate for this procedure and a proper consultation with your doctor is needed to find out if having a meniscus transplant is the best choice for you. Post surgery, the patient needs to rest the amount of time as advised by the doctor to allow complete healing of the knee. Complications from this surgery are very rare. If having pain, fever and pus drainage after the surgery, contact your doctor immediately without any delay.

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