Sequencing relationship
What we found
Sequence E11.621 before L97.4
E11.621 carries a Use Additional Code instruction covering L97.4: “code to identify site of ulcer (L97.4-, L97.5-)”
L97.4 carries a Code First instruction covering E11.621: “diabetic ulcers (E08.621, E08.622, E09.621, E09.622, E10.621, E10.622, E11.621, E11.622, E13.621, E13.622)”
What to review
On a claim that carries both, list E11.621 ahead of L97.4; the manifestation is never the principal diagnosis.
Why it matters
A "Code first" note means the underlying etiology is sequenced ahead of this manifestation code on the claim.
Source / rule
CMS ICD-10-CM tabular instructional notes