Other secondary osteonecrosis of right ulna

This code signifies the death of bone tissue in the right ulna due to an underlying condition, rather than a primary cause. It indicates a non-traumatic osteonecrosis that has developed as a consequence of another disease process or treatment.

Apply this code when documentation specifies osteonecrosis of the right ulna and clearly links it to a secondary cause such as corticosteroid use, systemic lupus erythematosus, or sickle cell disease. The physician's notes should explicitly state "secondary osteonecrosis" or provide sufficient detail to infer a secondary etiology.

• Ensure the documentation specifies "right ulna" and "secondary" osteonecrosis.
• Always code the underlying systemic disease or condition causing the osteonecrosis first, if known.
• Distinguish carefully from primary (idiopathic) osteonecrosis or osteonecrosis due to trauma.