Nondisp fx of base of unsp MC bone, subs for fx w nonunion

This code signifies a fracture at the base of an unspecified metacarpal bone that is not displaced, meaning the bone fragments remain in their normal alignment. The "subsequent encounter for fracture with nonunion" indicates that the fracture has failed to heal properly after an initial treatment period, and the patient is presenting for ongoing management of this complication.

This code is appropriate for follow-up visits where a patient is being treated for a previously diagnosed, nondisplaced metacarpal base fracture that has not united. This includes scenarios such as continued cast changes, physical therapy for nonunion, or evaluation for surgical intervention due to the persistent nonunion.

• Ensure documentation clearly states "nonunion" for the fracture.
• Verify the fracture location is the "base" of the metacarpal and that it is "nondisplaced."
• Confirm this is a subsequent encounter, not the initial treatment of the fracture.