Other secondary osteonecrosis, unspecified femur

This code signifies the death of bone tissue in an unspecified part of the femur due to an underlying condition, rather than a primary cause. This secondary osteonecrosis results from compromised blood supply to the femoral bone, leading to cellular death and potential bone collapse.

Apply this code when documentation confirms osteonecrosis of the femur, explicitly stating it is secondary to another medical condition (e.g., steroid use, alcoholism, sickle cell disease), but the specific location within the femur (e.g., head, shaft) is not documented. Supporting documentation should clearly link the osteonecrosis to an underlying systemic or iatrogenic cause.

• Always sequence the underlying cause of the secondary osteonecrosis first, if known and documented.
• Avoid using this code if a more specific anatomical site of femoral osteonecrosis (e.g., femoral head) is documented; instead, use the appropriate M87.35x subcategory.
• Ensure the medical record explicitly states "secondary" osteonecrosis; otherwise, consider codes for primary osteonecrosis (M87.0-) or other specified osteonecrosis (M87.8-).