Other secondary osteonecrosis, left ankle

This code signifies osteonecrosis affecting the left ankle, which is not primary (idiopathic) but rather a consequence of another underlying condition or event. This involves the death of bone tissue in the left ankle joint due to a loss of blood supply, leading to bone collapse and joint destruction.

Apply this code when documentation clearly indicates avascular necrosis of the left ankle that is secondary to a specific cause, such as corticosteroid use, trauma, systemic lupus erythematosus, or sickle cell disease. Ensure the medical record specifies "left ankle" and identifies the underlying etiology.

• Always sequence the underlying cause of the secondary osteonecrosis first, if known and applicable.
• Distinguish carefully between primary (idiopathic) and secondary osteonecrosis; this code is exclusively for secondary forms.
• Verify laterality (left vs. right) and the specific joint involved (ankle) to avoid miscoding.