Derangement of posterior horn of medial meniscus

This code signifies an internal derangement affecting the posterior aspect of the medial meniscus within the knee joint. This typically involves a tear or other structural disruption of this specific meniscal component, leading to symptoms like pain, locking, or instability.

Use this code when documentation clearly indicates a diagnosis of a tear or other derangement specifically localized to the posterior horn of the medial meniscus. This diagnosis is often confirmed by imaging studies such as MRI or arthroscopy.

• Ensure documentation specifies "posterior horn" and "medial meniscus" to support this granular code.
• Distinguish from derangements of other meniscal parts (e.g., anterior horn, lateral meniscus) or unspecified meniscal tears.
• Consider sequencing with codes for the underlying cause (e.g., trauma) if applicable, or associated conditions like osteoarthritis.