Oth disp fx of base of 1st MC bone, unsp hand, 7thP

This code signifies a fracture of the base of the first metacarpal bone (thumb) that is displaced and has previously been treated, but is now healing incorrectly (malunion). The specific hand is not documented.

Use this code for follow-up encounters where a patient presents with a previously diagnosed and treated displaced fracture of the thumb metacarpal base, and clinical or radiological findings confirm that the bone is healing in an anatomically incorrect position. This applies when the malunion is being addressed or monitored.

• Ensure documentation clearly specifies "malunion" and that the fracture is of the base of the first metacarpal.
• Verify the encounter is for follow-up care related to the fracture's healing, not initial treatment or routine follow-up without malunion.
• Confirm the laterality (left, right, or unspecified) is accurately reflected in the documentation; this code is for unspecified hand.