Disp fx of trapezium, unsp wrist, subs for fx w nonunion

This code signifies a fracture of the trapezium bone in an unspecified wrist, where the bone fragments are not properly aligned. The patient is in a later stage of treatment, and the fracture is failing to heal correctly, indicating a nonunion.

This code is appropriate for documenting follow-up care for a trapezium fracture that has not united, regardless of the specific wrist (left or right). It is used when the patient is seen for ongoing management of the nonunion, such as for re-evaluation, cast changes, or preparation for surgical intervention to promote healing.

• Requires an additional code for the specific type of nonunion (e.g., M84.4x).
• Ensure documentation clearly states "nonunion" and "subsequent encounter" for accurate application.
• Do not use for initial treatment or routine follow-up of a healing fracture.