Derangement of meniscus, not elsewhere classified

This code represents a non-specific internal derangement of the meniscus within the knee joint that doesn't fit into more precise categories like a tear or cyst. It indicates a functional impairment or mechanical issue of the meniscus without a clearly defined structural lesion.

Use this code when documentation describes meniscal symptoms such as locking, catching, or pain, but imaging (e.g., MRI) or arthroscopy does not reveal a specific tear or other classified meniscal pathology. It's appropriate for cases where a derangement is suspected but not definitively characterized as a tear.

• Avoid using this code if a specific meniscal tear (e.g., bucket handle, radial, complex) is documented; instead, use the appropriate specific tear code.
• Ensure documentation clearly states "derangement of meniscus" or similar language indicating a functional issue without a specified tear.
• Consider sequencing this code after a more definitive diagnosis if the derangement is secondary to another knee condition.