Review
Laterality relationship
What we found
Same condition, opposite side.S81.851 and S81.859 name the same condition on opposite sides of the body.
Same category and title, differing only in which side is affected — the documentation decides which one applies, and a bilateral code is reported only where the code set provides one.
What to review
Report the side the documentation names. Where the code set provides a bilateral code and both sides are documented, use it instead of the pair.
Why it matters
These codes share a category and title and differ only in the side affected. The documentation decides which applies, and a bilateral code is reported only where the code set provides one.
Source / rule
ICD-10-CM tabular list (laterality variant derived from the code title)