Excludes1 pair

E64.3 vs M83-

E64.3 and M83 are not coded together. ICD-10-CM declares them mutually exclusive with an Excludes1 note — the two conditions are not expected to occur together, so exactly one of them is normally correct for a given encounter. The Official Guidelines carve out one exception: if the two conditions are clearly unrelated to each other, both may be reported.

The official note, declared on M83
rickets (active) sequelae (E64.3)
E64.3

Sequelae of rickets

Billable
Chapter 4
Endocrine, nutritional and metabolic diseases
Section
E50-E64
Indexed under
  • Bowleg › rachitic
  • Craniotabes › rachitic
  • Deformity › rachitic, old or healed (acquired)
  • Genu › rachitic (old)
  • Hammer toe NEC › sequelae of rickets (late effect)
M83

Adult osteomalacia

Not billable
Chapter 13
Diseases of the musculoskeletal system and connective tissue
Section
M80-M85

These two codes sit in different chapters of the Tabular List, which is usually the clearest signal that they describe different underlying processes rather than different degrees of the same one.

Excludes1 is not always absolute: where two conditions covered by the note are genuinely unrelated, CMS guidance permits reporting both. Document the reasoning rather than assuming it. More on Excludes1 vs Excludes2 · FY2027