S99 vs T34
S99 (Other and unspecified injuries of ankle and foot) compared with T34 (Frostbite with tissue necrosis), from the official CMS tabular data. Both may be reported when both conditions are documented (Excludes2).
Can these codes be reported together?
Yes, when both are documented. S99 carries an Excludes2 note covering T34: “frostbite (T33-T34)”
Excludes2 marks distinct conditions — both may be reported when both are documented.
Side by side
| S99Other and unspecified injuries of ankle and foot | T34Frostbite with tissue necrosis | |
|---|---|---|
| Billing status | Non-billable header Report instead: S99.001A, S99.001B, S99.001D, S99.001G, S99.001K | Non-billable header Report instead: T34.011A, T34.011D, T34.011S, T34.012A, T34.012D |
| Classification | S00-T88 — Injury, Poisoning and Certain Other Consequences of External Causes (S00-T88) | S00-T88 — Injury, Poisoning and Certain Other Consequences of External Causes (S00-T88) |
| Definition | Other and unspecified injuries of ankle and foot is a non-billable ICD-10-CM category code (S99). | Frostbite with tissue necrosis is a non-billable ICD-10-CM category code (T34). |
| 7th character | — | The appropriate 7th character is to be added to each code from category T34 |
Derived from the official CMS ICD-10-CM tabular data (FY2026). Not billing advice; verify sequencing rules for the encounter. All data sources