An orthopedic group getting CO-231 on procedures billed together

This is an illustrative scenario: a composite of a situation that practices commonly face. It is not a Soft Home Global client and not any real practice, and it claims no result. The resolution steps come from our CO-231 guide, so the two never disagree.

The practice

A four-surgeon orthopedic group.

What they were seeing

Claims with two procedures on the same date come back with CO-231 for the second line, and the practice is unsure whether to add a modifier and resubmit.

What was actually going wrong

Some code pairs are defined as mutually exclusive — both cannot reasonably be performed at the same session. A modifier only belongs on the claim when the record shows the services were genuinely separate; adding one to get past the edit is the same kind of error OIG found at The Ohio State University Hospital, where modifier 59 was appended to procedures that were not separate.

How it is resolved

1. Read the operative or encounter note and decide which code actually describes what was done.
2. Where both genuinely happened at separate sites or sessions, the documentation must say so explicitly before a modifier is defensible.
3. Where it is a bilateral billing convention problem, rebill in the format that payer expects rather than appealing.
4. Where charge entry duplicated a line, correct and resubmit.

How to stop it coming back

Mutually exclusive pairs are published in the same NCCI tables as the CO-236 edits. A scrub that checks both catches this before it leaves the building.

Questions