Pathological fracture, oth site, subs for fx w malunion

This code signifies a bone fracture that occurred due to a pre-existing disease, rather than trauma, in an unspecified anatomical location other than the ankle, foot, or hand. It specifically indicates that the patient is receiving follow-up care for this pathological fracture, and the fracture has healed improperly, resulting in a malunion.

Apply this code when a patient presents for ongoing treatment of a pathological fracture that has healed in an unsatisfactory position. Documentation should clearly state "pathological fracture," specify "malunion," and indicate that this is a subsequent encounter for care related to the fracture. This code is appropriate when the specific site of the pathological fracture is not further specified in the medical record.

• Always sequence this code after the underlying disease causing the pathological fracture (e.g., osteoporosis, neoplasm).
• Ensure documentation explicitly states "malunion" and not just "nonunion" or "delayed union," as these have different codes.
• Avoid using this code if the specific anatomical site of the pathological fracture is known and a more specific M84.4- subcategory exists (e.g., M84.45XP for pathological fracture of the femur).