What causes a meniscal deficiency?
The meniscus has limited blood supply and damage to the fibrous tissue can cause the meniscus to break down, thin out or become jagged. The most common cause of meniscal deficiency is a meniscal tear and / or surgery.
A meniscal tear essentially renders the torn part of the meniscus non-functional. Since this segment of the meniscus can no longer transfer load, it can create a form of meniscal deficiency. The worst tear patterns for creating meniscal deficiency are radial tears and root tears since they are the biomechanical equivalent of having no meniscus at all.
The most common scenario to create meniscal deficiency, though, is post-surgery. Partial meniscectomy is the most common orthopedic procedure performed in the world. During this procedure, a torn, non-repairable piece of meniscus is removed. Depending on how much is taken out – meniscal deficiency can result. So, meniscal preservation with this common procedure is key to avoid this complicated outcome. The medial and lateral meniscus are not equivalent. In particular, the lateral compartment is particularly sensitive to meniscal deficiency and arthritis or chondral injury can result very rapidly after a partial lateral meniscectomy – even in a young patient!!