M23.0 - Cystic meniscus
M23.03 - Cystic meniscus, other medial meniscus
M23.031 - Cystic meniscus, other medial meniscus, right knee
M23.032 - Cystic meniscus, other medial meniscus, left knee
M23.039 - Cystic meniscus, other medial meniscus, unspecified knee