Derang of unsp medial meniscus due to old tear/inj, l knee

This code signifies a chronic or pre-existing internal derangement of the medial meniscus in the left knee, specifically attributed to an old tear or injury. It indicates a persistent issue rather than an acute event, affecting the structural integrity and function of the medial meniscal cartilage.

Use this code when documentation clearly states a "derangement" or "disorder" of the left medial meniscus resulting from a prior, non-acute tear or injury. This is appropriate for patients presenting with ongoing symptoms like pain, locking, or instability in the left knee, where imaging or clinical history confirms an old meniscal lesion.

• Ensure documentation specifies "old tear" or "due to old injury" to differentiate from acute tears.
• Laterality is crucial; this code is specific to the left knee.
• Do not use for acute meniscal tears; refer to codes in the S83.2- category for acute injuries.