Cystic meniscus, posterior horn of medial meniscus, r knee

This code identifies a fluid-filled sac (cyst) located in the posterior aspect of the medial meniscus in the right knee. This condition often results from meniscal tears or degeneration, leading to synovial fluid extrusion and cyst formation. Patients typically experience localized pain, swelling, and sometimes a palpable mass.

Use this code when documentation clearly indicates a cystic lesion affecting the posterior horn of the medial meniscus in the right knee. This diagnosis is typically confirmed through imaging studies such as MRI, which can visualize the cyst and its relationship to the meniscus. Supporting documentation should include imaging reports and physician notes detailing the location and nature of the cyst.

• Ensure laterality (right knee) and specific meniscal location (posterior horn of medial meniscus) are clearly documented.
• Do not confuse with other meniscal derangements, such as tears without cyst formation.
• Consider sequencing this code with a meniscal tear code (e.g., M23.2xx) if the cyst is secondary to a tear.