ICDcodes.org
FY2027

T21.73 — Corrosion of third degree of upper back

Not billable

Is T21.73 billable?

No — T21.73 is a non-billable header code. T21.73 groups more specific codes and cannot be submitted on a claim. A valid ICD-10-CM code must be reported at the highest level of specificity available in its branch. Select one of the 3 billable codes beneath T21.73.

T21.73 at a glance

CodeT21.73
DescriptionCorrosion of third degree of upper back
BillableNo — header code
Code setICD-10-CM FY2027
Valid for encountersOctober 1, 2026 – September 30, 2027

How is T21.73 listed in the Alphabetic Index?

These are the routes through the Alphabetic Index that lead to T21.73. They show the wording a clinician may have documented, which often differs from the Tabular description.

  • Corrosion › back › upper › third degree (injury) (acid) (caustic) (chemical) (lime) (external) (internal)

Inclusion terms

Alternative wording in documentation that is classified to T21.73.

  • Corrosion of third degree of interscapular region

Code first — inherited from T21.7

The underlying condition below must be sequenced before T21.73. T21.73 describes a manifestation and cannot be the principal or first-listed diagnosis.

  • (T51-T65) to identify chemical and intent

Use additional code — inherited from Chapter 19

Report an additional code alongside T21.73 to fully describe the condition. T21.73 is sequenced first.

  • code to identify any retained foreign body, if applicable (Z18.-)

Use additional code — inherited from T20-T25

Report an additional code alongside T21.73 to fully describe the condition. T21.73 is sequenced first.

  • code from category T31 or T32 to identify extent of body surface involved

Use additional code — inherited from T21.7

Report an additional code alongside T21.73 to fully describe the condition. T21.73 is sequenced first.

  • external cause code to identify place (Y92)

Excludes2 — not included here — inherited from Chapter 19

The conditions below are not part of T21.73, but a patient may have both at the same time. When documentation supports it, T21.73 and the excluded code may both be reported.

  • birth trauma (P10-P15)
  • obstetric trauma (O70-O71)

Excludes2 — not included here — inherited from T21

The conditions below are not part of T21.73, but a patient may have both at the same time. When documentation supports it, T21.73 and the excluded code may both be reported.

  • 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)

What codes fall under T21.73? (3)

How long has T21.73 existed?

T21.73 has been in ICD-10-CM since at least FY2016, the earliest fiscal year on record here.

Derived from the official order files for FY2016–FY2026. FY2017 and FY2020 publish no order file, so those years are not covered.

What other codes are in the T21.7 family? (8)