Displ lateral mass fx 1st cervcal vert, 7thK

This diagnosis code indicates a specific fracture of the first cervical vertebra (atlas), where the lateral mass is broken and misaligned, and the fracture has failed to heal properly. The "subsequent encounter" designation means the patient is receiving routine care during the healing phase of this nonunion.

This code is appropriate for follow-up visits where a patient is being managed for a previously diagnosed displaced lateral mass fracture of the C1 vertebra that has not united. Documentation should clearly state "nonunion" and specify the "subsequent encounter" for ongoing treatment, such as cast changes, physical therapy, or monitoring for surgical intervention.

• Ensure documentation explicitly states "nonunion" and "subsequent encounter" for this specific fracture.
• Distinguish from initial encounters or malunion, which have different code assignments.
• Verify laterality if applicable, though C1 fractures are typically midline.