Osteonecrosis due to previous trauma, left fibula

This code signifies the death of bone tissue in the left fibula, specifically attributed to a prior traumatic injury. This condition, also known as avascular necrosis, results from an interruption of blood supply to the bone, leading to bone cell death and potential collapse.

Apply this code when documentation clearly indicates osteonecrosis of the left fibula and explicitly links its etiology to a previous traumatic event. This would typically be supported by imaging studies (e.g., MRI, X-ray) confirming the osteonecrosis and a patient history detailing a significant prior trauma to the lower leg.

• Ensure the documentation specifies "previous trauma" as the cause, not current trauma or other etiologies like steroid use.
• Verify laterality (left fibula) is clearly documented; do not assume.
• Consider sequencing this code after any acute injury codes if the trauma is recent and still being treated, but before if the osteonecrosis is a long-term sequela.