2027 ICD-10-CM Diagnosis Code T79.6XXATraumatic ischemia of muscle, initial encounter

ICD-10-CM Codes›S00–T88›T79›T79

ICD-10-CM T79.6XXA
CMSSource: CMS FY 2027 ICD-10-CM dataset · Effective Oct 1, 2026 – Sep 30, 2027

T79.6XXA is a billable ICD-10-CM diagnosis code for traumatic ischemia of muscle, initial encounter. The 7th character A marks it as an initial encounter code, used while the patient is receiving active treatment. It is valid on HIPAA claims for fiscal year 2027 (October 1, 2026 through September 30, 2027) and groups to MS-DRG 564 through 566, 963 through 965. Coders also document this condition as anterior tibial stress syndrome. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Other specified injury.

T79.6XXA no longer risk-adjusts for Medicare Advantage: it mapped to HCC 173 under the retired CMS-HCC V24 model through payment year 2025 but maps to no category in the live V28 model. It still risk-adjusts in the PACE (CMS-HCC V22) category 173, ESRD (V21) category 173, and ESRD (V24) category 173 for payment year 2027.

Code Identity

ICD-10-CM Code
T79.6XXA
Billable Status
Yes — Valid for Submission
Code Describes
Traumatic ischemia of muscle, initial encounter
Short Description
Traumatic ischemia of muscle, initial encounter
Same as the full description in the CMS dataset.
Parent Code
T79.6
Traumatic ischemia of muscle

Code Classification

ChapterS00–T88Injury, poisoning and certain other consequences of external causes
SectionT79Certain early complications of trauma
CategoryT79Certain early complications of trauma, not elsewhere classified
This CodeT79.6XXATraumatic ischemia of muscle, initial encounter

Medicare Risk Adjustment (HCC)Billing

T79.6XXA no longer risk-adjusts for Medicare Advantage: it maps to no payment category in the live CMS-HCC V28 model, although it still risk-adjusts in the other CMS models shown below.

CMS-HCC V28 (Medicare Advantage Payment Model)
Not mapped
Dropped in V28 see all codes that no longer risk-adjust
Prior Model (CMS-HCC V24)
HCC 173
V24 retired last contributed to a Medicare Advantage risk score in payment year 2025
Other CMS Models
PACE (CMS-HCC V22): HCC 173 · ESRD (V21): HCC 173 · ESRD (V24): HCC 173
ESRD V21 weights: 0.042 dialysis, 0.061–0.290 functioning graft · ESRD V24 weights: 0.050 dialysis, 0.000–0.341 functioning graft
Part D (RxHCC)
Not mapped
T79.6XXA does not risk-adjust in the RxHCC prescription drug model

Source: CMS Payment Year 2027 risk adjustment mappings and model software. Weights are relative factors, not dollar amounts; a beneficiary's total RAF also includes demographics and interactions. Browse all CMS-HCC categories.

Approximate SynonymsGuidance

Alternate terms and clinical phrases that map to this code.

  • Anterior tibial stress syndrome
  • Compartment syndrome of forearm
  • Compartment syndrome of upper limb due to traumatic injury
  • Deformity after injury
  • Ischemia of muscle due to traumatic injury
  • Tibial stress syndrome
  • Traumatic rhabdomyolysis
  • Volkmann contracture
  • Volkmann ischemic contracture following traumatic compartment syndrome

Coding GuidelinesGuidance

The appropriate 7th character is to be added to each code from block Certain early complications of trauma, not elsewhere classified (T79). Use the following options for the applicable episode of care:

  • A - initial encounter
  • D - subsequent encounter
  • S - sequela

Source: ICD-10-CM Official Guidelines for Coding and Reporting, FY 2027, published by CMS and the National Center for Health Statistics.

Instructional NotesGuidance

Instructions from the official ICD-10-CM Tabular List that apply to T79.6XXA: its own notes plus those printed at T79.6, T79, and Chapter 19. A note printed at a category, block or chapter applies to every code under it.

Excludes2

Not included here: the excluded condition is not part of this code, but a patient may have both, so both codes may be reported.

From T79.6 Traumatic ischemia of muscle applies to 3 codes
  • anterior tibial syndrome (M76.8)
  • compartment syndrome (traumatic) (T79.A-)
  • nontraumatic ischemia of muscle (M62.2-)
From T79 Certain early complications of trauma, not elsewhere classified applies to 54 codes
  • 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)
From Chapter 19 (S00-T88) Injury, poisoning and certain other consequences of external causes applies to 41,187 codes

Use Additional Code

Add a second code, after this one, to fully describe the condition.

From Chapter 19 (S00-T88) Injury, poisoning and certain other consequences of external causes applies to 41,187 codes
  • code to identify any retained foreign body, if applicable (Z18.-)

Notes

General instructions on how these codes are used.

From Chapter 19 (S00-T88) Injury, poisoning and certain other consequences of external causes applies to 41,187 codes
  • Use secondary code(s) from Chapter 20, External causes of morbidity, to indicate cause of injury. Codes within the T section that include the external cause do not require an additional external cause code
  • The chapter uses the S-section for coding different types of injuries related to single body regions and the T-section to cover injuries to unspecified body regions as well as poisoning and certain other consequences of external causes.

7th Character

Every code in the category takes a 7th character from the listed values, with the placeholder X filling any empty positions before it.

From T79 Certain early complications of trauma, not elsewhere classified applies to 54 codes
  • The appropriate 7th character is to be added to each code from category T79
Values for category T79 Encounter: Initial, Subsequent, Sequela
  • Ainitial encounter this code
  • Dsubsequent encounter
  • Ssequela

Source: CMS ICD-10-CM Tabular List. How to read instructional notes.

Referenced in Other NotesGuidance

Instructional notes printed at other codes that name T79.6XXA, its category, or a range that includes it.

Excludes1 3

These codes carry an Excludes1 note naming T79.6XXA: they are not reported together with it, unless the two conditions are unrelated.

  • M62.2 Nontraumatic ischemic infarction of muscle
    traumatic ischemia of muscle (T79.6) names T79.6, which includes this code
  • M62.2 Nontraumatic ischemic infarction of muscle
    Volkmann's ischemic contracture (T79.6) names T79.6, which includes this code
  • M62.82 Rhabdomyolysis
    traumatic rhabdomyolysis (T79.6) names T79.6, which includes this code

Excludes2 1

These codes carry an Excludes2 note naming T79.6XXA: its condition is not part of those codes, and both may be reported when the patient has both.

  • T79.A Traumatic compartment syndrome
    traumatic ischemic infarction of muscle (T79.6) names T79.6, which includes this code

Clinical ClassificationClinical

AHRQ’s CCSR groups this code into broader clinical categories.

CCSR INJ026
Other specified injury
Default principal diagnosis: inpatient Yes · outpatient Yes

Patient EducationClinical

Muscle Disorders

Your muscles help you move and help your body work. Different types of muscles have different jobs. There are many problems that can affect muscles. Muscle disorders can cause weakness, pain or even paralysis.

Read the full article at MedlinePlus

Courtesy of MedlinePlus, a service of the U.S. National Library of Medicine.

Convert T79.6XXA to ICD-9-CMHistory

The closest ICD-9-CM equivalents under the General Equivalence Mappings.

ICD-9-CM
958.6 Volkmann's isch contract
Approximate The match is approximate rather than exact.

Code HistoryHistory

FY 2016AddedAdded to the ICD-10-CM code setEffective October 1, 2015, the first year of ICD-10-CM.
FY 2017–2026No changes
FY 2027CurrentCurrent code set, no changesEffective October 1, 2026 through September 30, 2027.

Questions About T79.6XXAOverview

What is the ICD-10 code for traumatic ischemia of muscle, initial encounter?

The ICD-10-CM code for traumatic ischemia of muscle, initial encounter is T79.6XXA (sometimes written as T796XXA). It is billable on HIPAA-covered claims from October 1, 2026 through September 30, 2027.

Is T79.6XXA (Traumatic ischemia of muscle) a billable code?

Yes. This is a billable ICD-10-CM code, specific enough to report traumatic ischemia of muscle, initial encounter on HIPAA-covered claims from October 1, 2026 through September 30, 2027.

What does the 7th character A in T79.6XXA mean?

The final character A marks the initial encounter: use it while the patient is receiving active treatment for traumatic ischemia of muscle, such as an emergency visit or first evaluation.

What MS-DRG does T79.6XXA group to?

When traumatic ischemia of muscle, initial encounter is the principal diagnosis on an inpatient stay, it groups to MS-DRG 564, 964, 965, 566, 565, 963, with relative weights from 0.7374 to 2.6361 depending on complications. Higher weights mean higher Medicare reimbursement.

What is the ICD-9 equivalent of T79.6XXA?

Under the General Equivalence Mappings, traumatic ischemia of muscle, initial encounter converts to ICD-9-CM 958.6 (Volkmann's isch contract). The mapping is approximate, so confirm the match fits the documentation.

Does T79.6XXA risk-adjust for Medicare Advantage payment?

Not for Medicare Advantage. T79.6XXA mapped to HCC 173 in the retired CMS-HCC V24 model, which last determined payment in 2025, but it maps to no category in the live V28 model; see all codes that no longer risk-adjust. It still risk-adjusts in the PACE (CMS-HCC V22) category 173 (Traumatic Amputations and Complications), ESRD (V21) category 173 (Traumatic Amputations and Complications), and ESRD (V24) category 173 (Traumatic Amputations and Complications).