Osteonecrosis in diseases classified elsewhere, unsp forearm

This code signifies the death of bone tissue in an unspecified forearm due to an underlying medical condition. This osteonecrosis is a secondary manifestation of another disease process, rather than a primary bone disorder.

Apply this code when documentation clearly indicates osteonecrosis of the forearm as a complication or manifestation of a separate, specified disease (e.g., lupus, sickle cell anemia, steroid use). The medical record must specify the forearm but not a more precise location (e.g., radius or ulna).

• Always sequence the underlying disease first, as this code represents a manifestation.
• Ensure documentation specifies "unspecified forearm" and not a more precise bone (e.g., M90.531 for right radius).
• Avoid using this code if the osteonecrosis is not linked to another classified disease; consider codes from M87 for primary osteonecrosis.