Fx unsp carpal bone, unsp wrist, subs for fx w malunion

This code indicates a fracture of an unspecified carpal bone in an unspecified wrist that has previously been treated, but has healed in a misaligned or deformed position. Malunion signifies that the bone fragments have united, but with an unacceptable degree of angulation, rotation, or shortening, potentially leading to functional impairment.

This code is appropriate for follow-up encounters where a patient is being evaluated or treated for complications arising from a carpal bone fracture that has healed improperly. It is used when the specific carpal bone involved is not documented, and the laterality of the wrist is also not specified.

• Ensure documentation clearly states "malunion" and that the encounter is subsequent to the initial fracture treatment.
• Avoid using this code if the specific carpal bone (e.g., scaphoid, lunate) or the laterality (left/right) is known; instead, use a more specific code.
• This code should not be used for nonunion (failure of bone to heal) or delayed union (healing taking longer than expected).