Other secondary osteonecrosis, right fibula

This code signifies osteonecrosis of the right fibula that is not primary (idiopathic) and is due to an underlying cause. This condition involves the death of bone tissue in the right fibula due to a loss of blood supply, leading to bone collapse and potential joint destruction.

Apply this code when documentation clearly indicates osteonecrosis of the right fibula secondary to another condition, such as corticosteroid use, trauma, radiation, or a systemic disease. The medical record must specify the right fibula as the affected site and confirm the secondary nature of the osteonecrosis.

• Always sequence the underlying cause of the secondary osteonecrosis first, if known and applicable.
• Ensure documentation specifies "right fibula" and "secondary" to differentiate from other sites or primary osteonecrosis.
• Do not confuse with M87.164 (other primary osteonecrosis, right fibula) or codes for other bone sites.