9 - Meniscus tissue engineering

Abstract

Once thought to be vestigial tissue and routinely resected, the menisci of the knee are crucial components to joint protection, shock absorption, stabilization, and lubrication. Even today, partial meniscectomies are one of the most commonly performed orthopedic surgeries, with an estimated 1.7million carried out each year worldwide. As a result of the menisci's reduced healing potential, removal of damaged tissue is often the only possible course of action to offer symptomatic relief. However, removal of significant portions of the meniscus has been shown to alter the transmission loads across the knee joint, induce joint space narrowing, and cause progressive alterations in the articular cartilage that lead to osteoarthritis. Those with severe meniscal deficiencies do not have many options other than allowing these degenerative changes in the joint to occur. Unfortunately, these changes can become extremely painful, debilitating, and, in some cases, severe enough to warrant total knee replacement. While current research into meniscal replacement with allograft tissue or engineered designs have shown promising short-term results, there are still significant issues that need to be addressed before a long-term solution can become clinically relevant. Thus, no “gold-standard” meniscus replacement currently exists.