M85 vs Q78.8
M85 (Other disorders of bone density and structure) compared with Q78.8 (Other specified osteochondrodysplasias), from the official CMS tabular data. Do not report these codes together: the official tabular list marks them Excludes1.
Can these codes be reported together?
No — do not report together. M85 carries an Excludes1 note covering Q78.8: “osteopoikilosis (Q78.8)”
Sole exception: when the two conditions are documented as unrelated to each other (ICD-10-CM Official Guidelines, Section I.A.12.a).
Side by side
| M85Other disorders of bone density and structure | Q78.8Other specified osteochondrodysplasias | |
|---|---|---|
| Billing status | Non-billable header | Billable |
| Classification | M00-M99 — Diseases of the Musculoskeletal System and Connective Tissue (M00-M99) | Q00-Q99 — Congenital Malformations, Deformations and Chromosomal Abnormalities (Q00-Q99) |
| Definition | Other disorders of bone density and structure is a non-billable ICD-10-CM category code (M85). | Other specified osteochondrodysplasias is a billable ICD-10-CM diagnosis code (Q78.8). |
| Includes | — | Osteopoikilosis |
Derived from the official CMS ICD-10-CM tabular data (FY2026). Not billing advice; verify sequencing rules for the encounter. All data sources