Other secondary osteonecrosis, left foot

This code signifies osteonecrosis of the left foot that is not primary (idiopathic) but rather a consequence of another underlying condition or event. It involves the death of bone tissue in the foot due to a loss of blood supply, leading to pain, joint collapse, and potential disability.

Use this code when documentation clearly indicates osteonecrosis affecting the left foot, and the etiology is secondary, such as from corticosteroid use, trauma, systemic lupus erythematosus, or sickle cell disease. The physician's notes should specify the affected foot and the secondary nature of the osteonecrosis.

• Ensure documentation specifies "left foot" and the secondary nature of the osteonecrosis; otherwise, an unspecified or primary code may be more appropriate.
• Always sequence the underlying cause of the secondary osteonecrosis (e.g., corticosteroid-induced, trauma, systemic disease) before this code.
• Differentiate from primary (idiopathic) osteonecrosis, which would be coded with M87.0- series.