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

This code signifies a chronic internal derangement of the lateral meniscus in the left knee, resulting from a previously sustained tear or injury. It indicates a persistent mechanical issue within the joint due to an old meniscal lesion, affecting the normal function and stability of the knee.

Apply this code when documentation specifies a derangement of the left lateral meniscus attributed to an old or chronic tear or injury. This is appropriate for patients presenting with ongoing symptoms like locking, clicking, or instability, where imaging (e.g., MRI) confirms a chronic meniscal lesion.

• Ensure documentation clearly specifies "old tear" or "old injury" to differentiate from acute meniscal tears.
• Verify laterality (left knee) is explicitly stated in the medical record.
• Do not use this code for acute meniscal tears; refer to the M23.3- series for acute derangements.