Skip to main content

T21 vs T22.24

T21 (Burn and corrosion of trunk) compared with T22.24 (Burn of second degree of axilla), from the official CMS tabular data.

Summary

These codes can be reported together when both conditions are documented, because T21 lists T22.24 under Excludes2, which marks them as distinct conditions.

Official rule
What is different?

The conditions named.T21 is “Burn and corrosion of trunk”; T22.24 is “Burn of second degree of axilla”.

Registry fact

Can these codes be reported together?

Yes, when both are documented.T21 lists T22.24 under Excludes2: “burns and corrosion of axilla (T22.- with fifth character 4)”. Excludes2 marks distinct conditions that may both be reported when both are documented.

Official ruleGuide: Excludes1 vs Excludes2

Is there an Excludes1 relationship?

None.Neither entry carries an Excludes1 note that names the other code.

Official rule

Is there an Excludes2 relationship?

Yes.T21’s tabular entry: “burns and corrosion of axilla (T22.- with fifth character 4)”. The note covers T22.24.

Official ruleGuide: Excludes1 vs Excludes2

Is one more specific?

Not comparable.The codes sit in different categories; specificity is only comparable within one category.

Is one a parent or header code?

Both are headers.Both are non-billable headers, and neither contains the other.

Registry fact

Are there sequencing instructions?

None.Neither entry carries a Code First or Use Additional Code note that names the other.

Official rule

Are there other coding relationships?

None found.No laterality, encounter-phase, Table of Neoplasms, Table of Drugs and Chemicals, or history-versus-active-disease relationship links these codes.

MedCoder-derived

Official rule: a tabular instructional note or a section of the ICD-10-CM Official Guidelines, quoted as published. Registry fact: the codes’ own published attributes (titles, billable status, position in the hierarchy, code set). MedCoder-derived: a reading MedCoder computes from those facts; it is not itself a rule. How to read the labels

Can these codes be reported together?

Informational

Excludes2 relationship

T21
Burn and corrosion of trunk
↔
T22.24
Burn of second degree of axilla

What we found

Yes, when both are documented.T21 carries an Excludes2 note covering T22.24: “burns and corrosion of axilla (T22.- with fifth character 4)”

Excludes2 marks distinct conditions — both may be reported when both are documented.

What to review

Report both only when the documentation supports both conditions; otherwise report the one documented.

Guide: Excludes1 vs Excludes2Check these on a claim

Why it matters

An Excludes2 note means the excluded condition is not part of the code above it, but a patient can have both. Report both when both are documented.

Source / rule

CMS ICD-10-CM tabular instructional notes

Official guidance behind these answers

  • Section I.A.12.b — Excludes2 · applies to: Excludes2

    A type 2 Excludes note represents “Not included here.” An excludes2 note indicates that the condition excluded is not part of the condition represented by the code, but a patient may have both conditions at the same time. When an Excludes2 note appears under a code, it is acceptable to use both the code and the excluded code together, when appropriate.

    ICD-10-CM Official Guidelines FY2026

Quoted from the ICD-10-CM Official Guidelines for Coding and Reporting in effect for the release shown. The tabular notes above are the code-level instruction; these sections are the convention that says how such a note is applied. Source document (CMS PDF) · Release and checksum

Side by side

T21Burn and corrosion of trunkT22.24Burn of second degree of axilla
Billing statusNon-billable header

Report instead: T21.00XA, T21.00XD, T21.00XS, T21.01XA, T21.01XD

Non-billable header

Report instead: T22.241A, T22.241D, T22.241S, T22.242A, T22.242D

ClassificationS00-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)
DefinitionBurn and corrosion of trunk is a non-billable ICD-10-CM category code (T21).Burn of second degree of axilla is a non-billable ICD-10-CM category code (T22.24).
7th characterThe appropriate 7th character is to be added to each code from category T21The appropriate 7th character is to be added to each code from category T22
Includes
burns and corrosion of hip region
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]
Excludes2
burns and corrosion of axilla (T22.- with fifth character 4)
burns and corrosion of scapular region (T22.- with fifth character 6)
burns and corrosion of shoulder (T22.- with fifth character 5)
burn and corrosion of interscapular region (T21.-)
burn and corrosion of wrist and hand (T23.-)
Use additional code
code from category T31 or T32 to identify extent of body surface involved
external cause code to identify the source, place and intent of the burn (X00-X19, X75-X77, X96-X98, Y92)
code from category T31 or T32 to identify extent of body surface involved

Notes are the code’s own tabular entry, quoted as published. A note that names the other code is the one the verdict above rests on.

Edit this comparisonCheck a whole claim

Derived from the official CMS ICD-10-CM tabular data (FY2026). A coding-rule comparison, not billing advice: payer-specific edits and medical-necessity policy are outside its scope. All data sources