Derangement of lat mensc due to old tear/inj, left knee

This code signifies a chronic internal derangement of the lateral meniscus in the left knee, specifically resulting from a previously sustained tear or injury. It indicates a persistent functional impairment or mechanical issue within the knee joint due to the old meniscal damage.

Apply this code when documentation clearly indicates a left knee lateral meniscal derangement attributed to a past, not acute, tear or injury. This is appropriate for patients presenting with symptoms like locking, clicking, or instability stemming from a chronic meniscal lesion. Supporting documentation should specify "old tear," "chronic injury," or similar phrasing distinguishing it from an acute event.

• Ensure documentation explicitly states "old tear" or "chronic injury" of the lateral meniscus; avoid using for acute tears.
• Laterality is crucial; confirm the left knee is affected.
• Do not confuse with codes for acute meniscal tears or other types of meniscal derangement not specified as due to an old injury.