Osteonecrosis due to drugs, unspecified fibula

This code signifies the death of bone tissue in an unspecified fibula, specifically attributed to the adverse effects of medication. This condition, also known as avascular necrosis, results from an interruption of blood supply to the bone, leading to its collapse. The drug-induced etiology differentiates it from other causes of osteonecrosis.

Use this code when documentation clearly states osteonecrosis of the fibula and explicitly links it to drug use, but the specific fibula (right or left) is not identified. This diagnosis is typically supported by imaging studies (e.g., MRI, X-ray) showing bone necrosis and a patient history detailing relevant medication exposure.

• Ensure the medical record explicitly states "drug-induced" or "due to drugs" to support this etiology.
• If the laterality of the fibula (right or left) is documented, a more specific code from the M87.16- series should be used.
• Code the specific drug causing the osteonecrosis as an adverse effect (T36-T50 with a 5th or 6th character of 5) as an additional diagnosis.