Other secondary osteonecrosis, unspecified toe(s)

This code signifies osteonecrosis of an unspecified toe, where the bone death is a consequence of another underlying condition rather than a primary idiopathic cause. It indicates a localized area of bone tissue death in the toe(s) due to impaired blood supply, secondary to a systemic or local factor.

Apply this code when documentation specifies secondary osteonecrosis affecting an unspecified toe, and the specific toe (e.g., great toe, other toe) is not identified. This code is appropriate when the etiology is clearly secondary (e.g., corticosteroid use, trauma, systemic lupus erythematosus) but the precise toe involved is not documented.

• Avoid using this code if the specific toe affected is documented; instead, use a more specific code from the M87.37- series.
• Always code the underlying primary condition causing the secondary osteonecrosis first.
• Ensure documentation clearly states "secondary" osteonecrosis to differentiate from primary/idiopathic forms.