M66.0 vs M66.1
M66.0 (Rupture of popliteal cyst) compared with M66.1 (Rupture of synovium), 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. M66.1 carries an Excludes2 note covering M66.0: “rupture of popliteal cyst (M66.0)”
Excludes2 marks distinct conditions — both may be reported when both are documented.
Side by side
| M66.0Rupture of popliteal cyst | M66.1Rupture of synovium | |
|---|---|---|
| Billing status | Billable | Non-billable header |
| Classification | M00-M99 — Diseases of the Musculoskeletal System and Connective Tissue (M00-M99) | M00-M99 — Diseases of the Musculoskeletal System and Connective Tissue (M00-M99) |
| Definition | Rupture of popliteal cyst is a billable ICD-10-CM diagnosis code (M66.0). | Rupture of synovium is a non-billable ICD-10-CM category code (M66.1). |
| Includes | rupture that occurs when a normal force is applied to tissues that are inferred to have less than normal strength | rupture that occurs when a normal force is applied to tissues that are inferred to have less than normal strength Rupture of synovial cyst |
Derived from the official CMS ICD-10-CM tabular data (FY2026). Not billing advice; verify sequencing rules for the encounter. All data sources