The medial meniscus is an important shock absorber on the inside (medial) aspect of the knee joint. It absorbs about 50% of the shock of the medial compartment. Thus, when there is a medial knee injury such as a medial meniscus tear, it is very important to try to repair it because when it cannot be repaired, it will increase the load on the medial compartment, which ultimately leads to osteoarthritis.
A complex tear of the medial meniscus can include root attachment tears, radial tears, or horizontal cleavage tears. In many circumstances in patients with these tears, the meniscus needs to be trimmed out. However, this does increase the risk of osteoarthritis, especially in patients who continue to participate in impact activities. We have found that in the proper environment, with fairly normal articular cartilage and patient age, and neutral or near normal alignment, an attempt at a repair for these types of tears is justified. We believe that trying to stimulate improved healing environment through the use of bone marrow elements, platelet rich plasma (PRP), and a large number inside-out meniscal repair sutures, can lead to improved ability to heal these tears, especially in younger patients.
When a medial knee injury such as a complex tear of the medial meniscus needs to be resected, we strongly recommend that these patients be followed very closely. Patients need to report back to their physician if they have any pain or swelling with activities, because these are the signs of arthritis and may indicate further progression of arthritic changes. If this is present, further treatment to include activity modification, low impact exercising, unloader braces, injections, or possible meniscal transplantation may be indicated.
It is almost inevitable that when one has a significant amount of the medial meniscus resected that they will develop further arthritic changes over time. Because not everybody is the same, these changes can develop within a few weeks up to over a decade. Thus, one of the important things is to recognize that if one has any pain or swelling, they should follow up to make sure they are not developing any joint space narrowing or bone spurs, which would indicate that the medial compartment articular cartilage is wearing out.
