Is T79.A9XA a billable ICD-10-CM code?

Yes. T79.A9XA is a billable, specific ICD-10-CM code and is valid for submission on a claim.

Where does T79.A9XA sit in the tabular list?

Injury, poisoning and certain other consequences of external causes (S00-T88), in the block Certain early complications of trauma (T79).

What cannot be coded together with T79.A9XA?

T79.A9XA carries Excludes1 notes, which means the conditions they list can never be coded together with it on the same encounter. Some are written on the categories above T79.A9XA (T79.A) and apply to it just the same.

T79.A9XA

T79.A9XA — Traumatic compartment syndrome of other sites, initial encounter

Billable / specific codeICD-10-CM

T79.A9XA is a billable, specific ICD-10-CM code for traumatic compartment syndrome of other sites, initial encounter. It is valid for submission on a claim.

7th character "A" — initial encounter

The appropriate 7th character is to be added to each code from category T79

A: initial encounter
D: subsequent encounter
S: sequela

Excludes1 inherited from the categories above T79.A9XA

These are not written on T79.A9XA, but they bind it: a note on a category applies to every code beneath it. Billing T79.A9XA with anything listed here is a denial.

Written on T79.A — Traumatic compartment syndrome

fibromyalgia (M79.7)
nontraumatic compartment syndrome (M79.A-)

Excludes2 inherited from the categories above T79.A9XA

Also inherited, and the opposite of Excludes1: these conditions are not part of T79.A9XA, but a patient can have both, so you may code both.

Written on T79.A — Traumatic compartment syndrome

traumatic ischemic infarction of muscle (T79.6)

Written on T79 — Certain early complications of trauma, not elsewhere classified

acute respiratory distress syndrome (J80)
complications occurring during or following medical procedures (T80-T88)
complications of surgical and medical care NEC (T80-T88)
newborn respiratory distress syndrome (P22.0)

Risk adjustment

T79.A9XA does not map to an HCC and does not risk-adjust under CMS-HCC V28. That is normal — most ICD-10 codes do not. It still needs to be coded correctly; it just will not move a RAF score.

Medicare coverage

T79.A9XA is named in 2 Medicare coverage policies — 2 listing it as supporting medical necessity. Which of them applies to you depends on your Medicare contractor, and coverage genuinely differs by state.

A56421Billing and Coding: CT of the Abdomen and Pelvis
A57594Billing and Coding: Non-Invasive Peripheral Venous Vascular and Hemodialysis Access Studies

Code history

T79.A9XA has not changed since FY2024 — no addition, revision or deletion across the three most recent ICD-10-CM releases.

Related codes at this level

Codes that share T79.A9. If T79.A9XA is not quite right, the correct code is usually one of these.

Questions about T79.A9XA

Is T79.A9XA a billable ICD-10-CM code?: Yes. T79.A9XA is a billable, specific ICD-10-CM code and is valid for submission on a claim.
Where does T79.A9XA sit in the tabular list?: Injury, poisoning and certain other consequences of external causes (S00-T88), in the block Certain early complications of trauma (T79).
What cannot be coded together with T79.A9XA?: T79.A9XA carries Excludes1 notes, which means the conditions they list can never be coded together with it on the same encounter. Some are written on the categories above T79.A9XA (T79.A) and apply to it just the same.