Discoid Meniscus

Discoid meniscus is an abnormal congenital variant of meniscus. The incidence is relatively low, but higher incidence was found in East-Asian population. Incidence of discoid lateral meniscus range from 0.4% to 17%, while discoid medial meniscus range from 0.06% to 0.3%. Moreover, recent studies in Asian population found high incidence of bilateral discoid meniscus up to 97%. Discoid meniscus not only has abnormal morphology and vascularity but also abnormal in structural arrangement of collagenous fiber. Hence, discoid meniscus has a higher risk of tear. There are many classifications from classic Watanabe to the more clinically relevant Anh’s classification. Sign and symptoms, physical examination and radiological findings will be discussed in this paper. The treatment of discoid meniscus range from observation to surgical treatment. The decision making is depending on symptoms and patient characteristic. Algorithm of treatment will be proposed in this paper.