Updates in biological therapies for knee injuries: menisci.

The preservation of meniscal tissue is paramount for long-term joint function, especially in younger patients who are athletically active. Many studies have reported encouraging results following the repair of meniscus tears, including both simple longitudinal tears located in the periphery and complex multiplanar tears that extend into the central third avascular region. However, most types of meniscal lesions are managed with a partial meniscectomy. Options to restore the meniscus range from an allograft transplantation to the use of synthetic and biological technologies. Recent studies have demonstrated good long-term outcomes with meniscal allograft transplantation, although the indications and techniques continue to evolve, and the long-term chondroprotective potential of this approach has yet to be determined. Several synthetic implants, most of which are approved in the European market, have shown some promise for replacing part of or the entire meniscus, including collagen meniscal implants, hydrogels, and polymer scaffolds. Currently, there is no ideal implant generated by means of tissue engineering. However, meniscus tissue engineering is a fast developing field that promises to develop an implant that mimics the histologic and biomechanical properties of a native meniscus.