M95.5 vs O33
M95.5 and O33 can never be reported together. ICD-10-CM declares them mutually exclusive with an Excludes1 note, meaning the two conditions cannot occur in the same patient — so exactly one of them is correct for any given encounter.
The official note, declared on M95.5
maternal care for known or suspected disproportion (O33.-)
M95.5
Acquired deformity of pelvis
Billable
- Chapter 13
- Diseases of the musculoskeletal system and connective tissue
- Section
- M95
Indexed under
- Nägele's pelvis
- Platypelloid pelvis
- Contraction, contracture, contracted › pelvis (s)
- Deformity › ilium
- Deformity › ischium
O33
Maternal care for disproportion
Not billable
- Chapter 15
- Pregnancy, childbirth and the puerperium
- Section
- O30-O48
Use when the record says
- the listed conditions as a reason for observation, hospitalization or other obstetric care of the mother, or for cesarean delivery before onset of labor
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