A discoid meniscus is a developmental meniscus that becomes cake-like, large and thick. The discoid meniscus in adolescents may not necessarily be finalized. The adolescent discoid meniscus may also have popping, knee rattling and pain, but this is acceptable as long as there is no severe painful rupture, and the discoid meniscus will gradually develop into a normal meniscus as it develops and adapts. However, once the disc meniscus is still present in adulthood, the disc meniscus will sooner or later be ruptured, most often on the lateral side. Once the disc meniscus has ruptured, this will produce recurrent joint pain, popping and joint swelling. At this point the disc meniscus needs to be treated and a disc menoplasty is required to partially remove the excess meniscus and to repair the meniscus into a half-moon shaped meniscus that will provide normal protection.