M24.6 vs M25.6
M24.6 (Ankylosis of joint) compared with M25.6 (Stiffness of joint, not elsewhere classified), 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. M24.6 carries an Excludes1 note covering M25.6: “stiffness of joint without ankylosis (M25.6-)”
Sole exception: when the two conditions are documented as unrelated to each other (ICD-10-CM Official Guidelines, Section I.A.12.a).
No — do not report together. M25.6 carries an Excludes1 note covering M24.6: “ankylosis of joint (M24.6-)”
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
| M24.6Ankylosis of joint | M25.6Stiffness of joint, not elsewhere classified | |
|---|---|---|
| Billing status | Non-billable header | 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 | Ankylosis of joint is a non-billable ICD-10-CM category code (M24.6). | Stiffness of joint, not elsewhere classified is a non-billable ICD-10-CM category code (M25.6). |
Derived from the official CMS ICD-10-CM tabular data (FY2026). Not billing advice; verify sequencing rules for the encounter. All data sources