Osteonecrosis due to previous trauma, unspecified foot

This code signifies the death of bone tissue in an unspecified foot, resulting from a prior traumatic injury. This avascular necrosis occurs when the blood supply to the bone is disrupted, leading to bone collapse and potential joint destruction. The "unspecified foot" indicates that the specific foot (left or right) is not documented.

Apply this code when documentation clearly states osteonecrosis of the foot and explicitly links its etiology to a previous traumatic event. Supporting documentation should include imaging reports (e.g., MRI, X-ray) confirming avascular necrosis and a history of trauma to the affected foot.

• Ensure the documentation specifies "previous trauma" as the cause; do not use for idiopathic or other etiologies.
• If the specific foot (left or right) is documented, use the more specific codes M87.271 (right) or M87.272 (left).
• Code any associated pathological fractures separately if present and documented.