Cystic meniscus, unspecified medial meniscus, left knee

This code indicates the presence of a fluid-filled sac (cyst) within or adjacent to the medial meniscus of the left knee. The specific location within the medial meniscus is not further specified in the documentation.

Apply this code when documentation clearly states a cystic meniscus affecting the left medial meniscus, without further detail regarding the specific meniscal horn (e.g., anterior, posterior). This diagnosis is typically made via imaging studies such as MRI.

• Ensure the documentation specifies "left knee" and "medial meniscus."
• Do not use this code if the specific meniscal horn (anterior or posterior) is identified; use a more specific code from the M23.0 series.
• Consider sequencing this code after any traumatic injury codes if the cyst is a result of trauma.