Stress fracture, left fibula, subs for fx w nonunion

This diagnosis code indicates a stress fracture affecting the left fibula that has not healed properly, requiring ongoing treatment. It signifies a complication where the bone fragments have failed to unite after a previous stress fracture.

Apply this code when a patient presents for follow-up care of a previously diagnosed stress fracture of the left fibula that has developed into a nonunion. Documentation should clearly state "nonunion" or "failed healing" of the stress fracture and specify the left fibula.

• Ensure documentation explicitly states "nonunion" and identifies the left fibula.
• This code is for subsequent encounters; an initial encounter for the nonunion would use a different seventh character.
• Do not confuse with malunion (M84.4-) or routine healing of a stress fracture.