The meniscus is a C-shaped piece of cartilage that provides a cushion between the thighbone (femur) and shinbone (tibia). The main function of the C-shaped cartilage is load transmission. The meniscus distributes forces between the femur and tibia over a larger surface area to reduce the point-contact forces of articular cartilage. It aids in joint lubrication and nutrition, and the medial (inner) meniscus acts as a “backup” stabilizer to the knee following anterior cruciate ligament injury.
Treatment for symptomatic meniscal tears may include meniscus repair and partial meniscectomy. If a meniscus is so badly damaged it cannot be repaired, it may need to be removed or trimmed out for meniscus transplant. A meniscus transplant is potentially the most technically involved surgery in sports medicine. It involves an implantation of a fresh-frozen cadaver meniscus, which is preoperatively sized to the patient’s knee using arthroscopic surgery. Either a bone trough (lateral) or bone tunnels (medial) are used to anchor the boney attachments, and sutures are then placed to the native meniscal rim or capsule.
Meniscal injuries of the knee can occur at any age, but are most common in people age 30 to 50 years. Younger people tend to injure (tear) their meniscus in athletic endeavors, while older people sustain tears from minimal insults, such as twisting while getting out of a chair or golf cart.
Meniscal transplants are not right for everyone. If the patient already has arthritis in the knee, a meniscal transplant may not be recommended. But for a select group of people, meniscal transplants can offer significant pain relief.
Clinical studies have demonstrated a 75% to 85% success rate for meniscal transplantation, defined as reduction in pain/swelling, increase in activity, and delay in the inevitable progression of post-traumatic arthritis.