S90.56 vs S91.05
S90.56 (Insect bite (nonvenomous) of ankle) compared with S91.05 (Open bite of ankle), 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. S91.05 carries an Excludes1 note covering S90.56: “superficial bite of ankle (S90.56-, S90.57-)”
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
| S90.56Insect bite (nonvenomous) of ankle | S91.05Open bite of ankle | |
|---|---|---|
| Billing status | Non-billable header Report instead: S90.561A, S90.561D, S90.561S, S90.562A, S90.562D | Non-billable header Report instead: S91.051A, S91.051D, S91.051S, S91.052A, S91.052D |
| 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 | Insect bite (nonvenomous) of ankle is a non-billable ICD-10-CM category code (S90.56). | Open bite of ankle is a non-billable ICD-10-CM category code (S91.05). |
| 7th character | The appropriate 7th character is to be added to each code from category S90 | The appropriate 7th character is to be added to each code from category S91 |
Derived from the official CMS ICD-10-CM tabular data (FY2026). Not billing advice; verify sequencing rules for the encounter. All data sources