Osteonecrosis due to drugs, left femur

This code signifies the death of bone tissue in the left thigh bone (femur) resulting from the use of certain medications. This condition leads to the collapse of the bone and joint, causing pain and functional impairment.

Apply this code when documentation explicitly states osteonecrosis of the left femur and attributes its etiology to drug therapy. Common drug classes implicated include corticosteroids and bisphosphonates. Supporting documentation should include physician notes detailing the diagnosis, affected site, and the drug cause.

• Ensure the documentation specifies "left" femur; otherwise, an unspecified or bilateral code may be more appropriate.
• Always code the underlying drug causing the osteonecrosis as an adverse effect (T36-T50 with a 5th or 6th character of 5).
• Distinguish from osteonecrosis due to other etiologies, such as trauma or idiopathic causes, which have different code assignments.