Unsp fx l low leg, subs for opn fx type 3A/B/C w nonunion

This code signifies a fracture of the left lower leg, where the specific bone involved (tibia, fibula, or both) is not documented. It indicates a subsequent encounter for a severe open fracture (Type IIIA, IIIB, or IIIC) that has failed to heal properly, resulting in nonunion.

Apply this code when a patient presents for ongoing management of a previously treated, unspecified open fracture of the left lower leg, and the physician explicitly documents nonunion. This is appropriate for follow-up visits, surgical interventions for nonunion, or rehabilitation related to the unhealed fracture.

• Ensure documentation clearly states "nonunion" and specifies the left lower leg.
• Verify the encounter is "subsequent" and not the initial treatment for the fracture.
• Do not use if the specific bone (tibia or fibula) is identified; use a more specific code for that bone.