Unsp disp fx of fourth cervcal vert, subs for fx w nonunion

This code indicates a fracture of the fourth cervical vertebra that is displaced and has not healed properly, despite previous treatment. It specifically applies when the patient is receiving ongoing care for this unhealed fracture.

Use this code for follow-up encounters where a patient is being treated for a previously diagnosed, displaced C4 vertebral fracture that has progressed to nonunion. Documentation should clearly state "nonunion" and specify the fourth cervical vertebra and displacement.

• Ensure documentation explicitly states "nonunion" and "displaced" for the C4 fracture.
• Verify laterality if applicable, though cervical vertebrae are midline.
• Distinguish from malunion (S12.300P) and routine healing (S12.300D/G/S).