M66.0 vs M71.2
M66.0 (Rupture of popliteal cyst) compared with M71.2 (Synovial cyst of popliteal space [Baker]), 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. M71.2 carries an Excludes1 note covering M66.0: “synovial cyst of popliteal space with rupture (M66.0)”
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
| M66.0Rupture of popliteal cyst | M71.2Synovial cyst of popliteal space [Baker] | |
|---|---|---|
| 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). | Synovial cyst of popliteal space [Baker] is a non-billable ICD-10-CM category code (M71.2). |
| Includes | rupture that occurs when a normal force is applied to tissues that are inferred to have less than normal strength | — |
Derived from the official CMS ICD-10-CM tabular data (FY2026). Not billing advice; verify sequencing rules for the encounter. All data sources