M66.231 (Spontaneous rupture of extensor tendons, right forearm) compared with M66.232 (Spontaneous rupture of extensor tendons, left forearm), from the official CMS tabular data. M66.231 and M66.232 code the same condition on opposite sides.
Same condition; these differ only in which side is documented.
These codes share a category and title and differ only in the side affected. The documentation decides which applies, and a bilateral code is reported only where the code set provides one.
Source: ICD-10-CM tabular list (laterality variant derived from the code title)
Same condition, opposite side. M66.231 and M66.232 name the same condition on opposite sides of the body.
Same category and title, differing only in which side is affected — the documentation decides which one applies, and a bilateral code is reported only where the code set provides one.
| M66.231Spontaneous rupture of extensor tendons, right forearm | M66.232Spontaneous rupture of extensor tendons, left forearm | |
|---|---|---|
| Billing status | Billable | Billable |
| Classification | M00-M99 — Diseases of the musculoskeletal system and connective tissue | M00-M99 — Diseases of the musculoskeletal system and connective tissue |
| Definition | Spontaneous rupture of extensor tendons, right forearm is a billable ICD-10-CM diagnosis code (M66.231). | Spontaneous rupture of extensor tendons, left forearm is a billable ICD-10-CM diagnosis code (M66.232). |
| 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 |
Derived from the official CMS ICD-10-CM tabular data (FY2026). Not billing advice; verify sequencing rules for the encounter. All data sources