Osteonecrosis due to previous trauma, left ankle

This code signifies the death of bone tissue in the left ankle joint, specifically attributed to a prior traumatic injury. This condition, also known as avascular necrosis, results from an interruption of blood supply to the bone, leading to its collapse and potential joint destruction.

Apply this code when documentation clearly states osteonecrosis of the left ankle and explicitly links its etiology to a previous trauma. This includes cases where a fracture, dislocation, or other significant injury to the ankle preceded the development of avascular necrosis.

• Ensure the documentation specifies "left" ankle; laterality is crucial for accurate coding.
• Verify that the physician explicitly states the osteonecrosis is "due to previous trauma" and not another cause (e.g., steroid-induced, idiopathic).
• Consider sequencing this code after a code for the specific previous trauma, if still active or relevant to the current encounter.