Pathological fracture, left femur, subs for fx w malunion

This code signifies a fracture of the left femur that occurred due to an underlying disease process, rather than trauma. The patient is in the healing phase of this pathological fracture, but the bone has healed in an abnormal alignment, resulting in a malunion.

Apply this code for follow-up encounters where a patient is being treated for a previously diagnosed pathological fracture of the left femur that has healed incorrectly. Documentation should clearly state "pathological fracture," specify the left femur, and indicate the presence of a malunion during a subsequent encounter.

• Ensure documentation explicitly states "pathological fracture" and not just "fracture" to differentiate from traumatic fractures.
• Verify the laterality (left femur) is clearly documented.
• Distinguish from nonunion (M84.452N) where the fracture has failed to heal, versus malunion where it has healed incorrectly.