Unsp fx shaft of humerus, left arm, subs for fx w malunion

This code signifies a fracture of the main body (shaft) of the left upper arm bone (humerus) that was previously treated but has not healed correctly, resulting in a malunion. The specific type of fracture of the shaft was not documented.

Use this code for follow-up encounters where a patient is being managed for a left humeral shaft fracture that has healed in an unsatisfactory position or alignment. This applies when the initial fracture type of the shaft was not specified in the documentation.

• Ensure documentation clearly states "malunion" and specifies the left humerus shaft.
• Verify that the encounter is subsequent to the initial fracture treatment.
• Do not use if the specific type of humeral shaft fracture (e.g., transverse, oblique) is documented; a more specific code would be appropriate.