T23.491 (Corrosion of unspecified degree of multiple sites of right wrist and hand) compared with T23.499 (Corrosion of unspecified degree of multiple sites of unspecified wrist and hand), from the official CMS tabular data. T23.491 and T23.499 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. T23.491 and T23.499 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.
| T23.491Corrosion of unspecified degree of multiple sites of right wrist and hand | T23.499Corrosion of unspecified degree of multiple sites of unspecified wrist and hand | |
|---|---|---|
| Billing status | Non-billable header | Non-billable header |
| Classification | S00-T88 — Injury, poisoning and certain other consequences of external causes | S00-T88 — Injury, poisoning and certain other consequences of external causes |
| Definition | Corrosion of unspecified degree of multiple sites of right wrist and hand is a non-billable ICD-10-CM category code (T23.491). | Corrosion of unspecified degree of multiple sites of unspecified wrist and hand is a non-billable ICD-10-CM category code (T23.499). |
| 7th character | The appropriate 7th character is to be added to each code from category T23 | The appropriate 7th character is to be added to each code from category T23 |
| Includes | burns and corrosions of first degree [erythema] burns and corrosions of second degree [blisters][epidermal loss] burns and corrosions of third degree [deep necrosis of underlying tissue] [full- thickness skin loss] | burns and corrosions of first degree [erythema] burns and corrosions of second degree [blisters][epidermal loss] burns and corrosions of third degree [deep necrosis of underlying tissue] [full- thickness skin loss] |
| Use additional code | external cause code to identify place (Y92) code from category T31 or T32 to identify extent of body surface involved | external cause code to identify place (Y92) code from category T31 or T32 to identify extent of body surface involved |
| Code first | (T51-T65) to identify chemical and intent | (T51-T65) to identify chemical and intent |
Derived from the official CMS ICD-10-CM tabular data (FY2026). Not billing advice; verify sequencing rules for the encounter. All data sources