Displ commnt fx shaft of ulna, unsp arm, 7thN

This code signifies a complex injury involving a comminuted fracture of the ulna shaft that is displaced, meaning the bone fragments are not in their normal alignment. It specifically indicates an open fracture (where the bone has broken through the skin) classified as Type IIIA, IIIB, or IIIC, and importantly, the fracture has failed to heal properly (nonunion) during a subsequent treatment encounter.

Apply this code when documenting follow-up care for a patient with a previously diagnosed displaced, comminuted open fracture (Type IIIA, IIIB, or IIIC) of the ulnar shaft in an unspecified arm, and the physician explicitly states that nonunion is present. This code is appropriate for encounters focused on managing the nonunion, such as planning for revision surgery or continued conservative management of the unhealed fracture.

• Ensure documentation clearly specifies "nonunion" and the open fracture type (IIIA, IIIB, or IIIC).
• Verify laterality (left or right arm) if available; "unspecified arm" should only be used when laterality is truly unknown.
• This code is for subsequent encounters; an initial encounter for this type of fracture would use a different code.