M65.042 (Abscess of tendon sheath, left hand) compared with M65.049 (Abscess of tendon sheath, unspecified hand), from the official CMS tabular data. M65.042 and M65.049 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. M65.042 and M65.049 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.
| M65.042Abscess of tendon sheath, left hand | M65.049Abscess of tendon sheath, unspecified hand | |
|---|---|---|
| Billing status | Billable | Billable |
| 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 | Abscess of tendon sheath, left hand is a billable ICD-10-CM diagnosis code (M65.042). | Abscess of tendon sheath, unspecified hand is a billable ICD-10-CM diagnosis code (M65.049). |
| Use additional code | code (B95-B96) to identify bacterial agent. | code (B95-B96) to identify bacterial agent. |
Derived from the official CMS ICD-10-CM tabular data (FY2026). Not billing advice; verify sequencing rules for the encounter. All data sources