Oth fx shaft of r ulna, subs for opn fx type I/2 w malunion

This code indicates a malunion of an open fracture (Type I or II) of the shaft of the right ulna, meaning the bone has healed in an incorrect anatomical position. This diagnosis is made during a follow-up visit after the initial treatment of the fracture. The malunion can lead to functional impairment and pain in the patient's right forearm.

Use this code for a patient presenting for ongoing care of a previously sustained open fracture of the right ulnar shaft, where imaging or clinical assessment confirms that the bone has healed in a misaligned position. This applies to subsequent encounters for the management of the malunion, such as planning for corrective surgery or monitoring conservative treatment.

• Ensure documentation specifies "malunion" and not "nonunion" or "delayed union."
• Verify the fracture was initially classified as an open fracture Type I or II.
• Confirm the encounter is a "subsequent encounter" for the fracture's healing complication.