The purpose of the meniscus
The meniscus consists of two C-shaped pieces of cartilage that act as a cushion in the knee joint. The meniscus protects the smooth cartilage and bone at the tips of the tibia and femur from impact damage. Two menisci inhabit the knee joint, the medial meniscus in the center of the knee and the lateral meniscus on the outer edge of the knee. Without the meniscus functioning properly the knee joint can catch, click, loose range of motion, and over time succumb to a painful degenerative condition called osteoarthritis.
Damage to the meniscus
If you have ever heard someone say that they tore the cartilage in their knee they most likely mean that they tore their meniscus. Twisting motions and impacts on bent knees can tear the meniscus by forcing it into unnatural movement patterns. Many times, the tearing of the meniscus may heal on its own if only a minor tear and the area has good vascular access. Extensive, irregular tears in areas with poor oxygenation, may need surgical repair or debris clean up for optimal meniscus function. Severe cases may need the meniscus removed entirely. Without cushion a knee joint lacking a meniscus receives damage from the jarring impact of bone on bone. Development of osteoarthritis eventually degrades the joint to a painful and nonfunctional point that can warrant total knee replacement. For many older patients with severe osteoarthritis doctors consider performing a total knee replacement as the proper intervention, but active people younger than 55 can consider an alternative treatment: meniscus transplant surgery.
Meniscus Transplant Surgery
A meniscal transplant replaces the damaged meniscus with donor cartilage. Meniscal transplants have specific selection criteria. If you already have arthritis in your knee, a meniscus transplant may not help you, but for younger patients with irreparable meniscus damage a meniscus transplant can offer significant pain relief without causing the need for total knee replacement a few years down the road. Candidates for meniscus transplant roughly fit into the following selection criteria: younger than 55, missing more than half the meniscus, severe and persistent pain, knee instability, minimal to no arthritis, normal knee alignment, stable knee ligaments, and having a healthy weight.