Excludes1 pair
M27.0 vs M27.4-
M27.0 and M27.4 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 M27.4
latent bone cyst of jaw (M27.0)
M27.0
Developmental disorders of jaws
Billable
- Chapter 13
- Diseases of the musculoskeletal system and connective tissue
- Section
- M26-M27
Use when the record says
- Latent bone cyst of jaw
- Stafne's cyst
- Torus mandibularis
- Torus palatinus
Indexed under
- Stafne's cyst or cavity
- Torus (mandibularis) (palatinus)
- Cyst › Stafne's
- Disorder › jaw, developmental
- Cyst › bone NEC › specified type NEC › jaw › latent
M27.4
Other and unspecified cysts of jaw
Not billable
- Chapter 13
- Diseases of the musculoskeletal system and connective tissue
- Section
- M26-M27
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