Q79.8 vs Q83
Q79.8 (Other congenital malformations of musculoskeletal system) compared with Q83 (Congenital malformations of breast), from the official CMS tabular data. Both may be reported when both conditions are documented (Excludes2).
Can these codes be reported together?
Yes, when both are documented. Q83 carries an Excludes2 note covering Q79.8: “absence of pectoral muscle (Q79.8)”
Excludes2 marks distinct conditions — both may be reported when both are documented.
Side by side
| Q79.8Other congenital malformations of musculoskeletal system | Q83Congenital malformations of breast | |
|---|---|---|
| Billing status | Billable | Non-billable header |
| Classification | Q00-Q99 — Congenital Malformations, Deformations and Chromosomal Abnormalities (Q00-Q99) | Q00-Q99 — Congenital Malformations, Deformations and Chromosomal Abnormalities (Q00-Q99) |
| Definition | Other congenital malformations of musculoskeletal system is a billable ICD-10-CM diagnosis code (Q79.8). | Congenital malformations of breast is a non-billable ICD-10-CM category code (Q83). |
| Includes | Absence of muscle Absence of tendon Accessory muscle Amyotrophia congenita | — |
Derived from the official CMS ICD-10-CM tabular data (FY2026). Not billing advice; verify sequencing rules for the encounter. All data sources