2027 ICD-10-CM Diagnosis Code S85.009AUnspecified injury of popliteal artery, unspecified leg, initial encounter

ICD-10-CM Codes›S00–T88›S80-S89›S85

ICD-10-CM S85.009A
CMSSource: CMS FY 2027 ICD-10-CM dataset · Effective Oct 1, 2026 – Sep 30, 2027

S85.009A is a billable ICD-10-CM diagnosis code for unspecified injury of popliteal artery, unspecified leg, 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 913 through 914, 963 through 965. As a secondary diagnosis, it counts as a major complication or comorbidity (MCC) and places an inpatient stay in the highest severity level of its MS-DRG family. It does not count, however, when the principal diagnosis is one of 90 closely related codes. The code is flagged as an unspecified code, since codes identifying laterality exist in the same family. Coders also document this condition as closed injury, popliteal artery. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Injury to blood vessels, initial encounter.

Code Identity

ICD-10-CM Code
S85.009A
Billable Status
Yes — Valid for Submission
Code Describes
Unspecified injury of popliteal artery, unspecified leg, initial encounter
Short Description
Unsp injury of popliteal artery, unsp leg, init encntr
Parent Code
S85.009
Unspecified injury of popliteal artery, unspecified leg

Code Classification

ChapterS00–T88Injury, poisoning and certain other consequences of external causes
SectionS80-S89Injuries to the knee and lower leg
CategoryS85Injury of blood vessels at lower leg level
This CodeS85.009AUnspecified injury of popliteal artery, unspecified leg, initial encounter

Code EditsBilling

Medicare Code Editor checks that affect claim validity for S85.009A.

Unspecified codes
Unspecified codes exist in the ICD-10-CM classification for circumstances when documentation in the medical record does not provide the level of detail needed to support reporting a more specific code. However, in the inpatient setting, there should generally be very limited and rare circumstances for which the laterality (right, left, bilateral) of a condition is unable to be documented and reported. The following pages contain the list of unspecified ICD-10-CM diagnosis codes for which there is a more specific code to identify laterality (right, left, bilateral) within that code family.

Approximate SynonymsGuidance

Alternate terms and clinical phrases that map to this code.

  • Closed injury, popliteal artery
  • Injury of popliteal artery
  • Open injury, popliteal artery

Coding GuidelinesGuidance

The appropriate 7th character is to be added to each code from block Injury of blood vessels at lower leg level (S85). 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 S85.009A: its own notes plus those printed at S85, block S80-S89, 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 S85 Injury of blood vessels at lower leg level applies to 270 codes
  • injury of blood vessels at ankle and foot level (S95.-)
From Block S80-S89 Injuries to the knee and lower leg applies to 4,680 codes
  • burns and corrosions (T20-T32)
  • frostbite (T33-T34)
  • injuries of ankle and foot, except fracture of ankle and malleolus (S90-S99)
  • insect bite or sting, venomous (T63.4)
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.-)

Code Also

A second code may be needed to fully describe the condition; the note gives no sequencing direction.

From S85 Injury of blood vessels at lower leg level applies to 270 codes
  • any associated open wound (S81.-)

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 S85 Injury of blood vessels at lower leg level applies to 270 codes
  • The appropriate 7th character is to be added to each code from category S85
Values for category S85 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 S85.009A, its category, or a range that includes it.

Excludes2 2

These codes carry an Excludes2 note naming S85.009A: its condition is not part of those codes, and both may be reported when the patient has both.

  • S75 Injury of blood vessels at hip and thigh level
    injury of blood vessels at lower leg level (S85.-) names S85.-, which includes this code
  • S75 Injury of blood vessels at hip and thigh level
    injury of popliteal artery (S85.0) names S85.0, which includes this code

Clinical ClassificationClinical

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

CCSR INJ016
Injury to blood vessels, initial encounter
Default principal diagnosis: inpatient Yes · outpatient Yes

Patient EducationClinical

Leg Injuries and Disorders

Your legs are made up of bones, blood vessels, muscles, and other connective tissue. They are important for motion and standing. Playing sports, running, falling, or having an accident can damage your legs. Common leg injuries include sprains and strains, joint dislocations, and fractures (broken bones).

Read the full article at MedlinePlus

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

Convert S85.009A to ICD-9-CMHistory

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

ICD-9-CM
904.41 Injury popliteal artery
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 S85.009AOverview

Is S85.009A (Unspecified injury of popliteal artery, unspecified leg) a billable code?

Yes. This is a billable ICD-10-CM code, specific enough to report unspecified injury of popliteal artery, unspecified leg, initial encounter on HIPAA-covered claims from October 1, 2026 through September 30, 2027.

What does the 7th character A in S85.009A mean?

The final character A marks the initial encounter: use it while the patient is receiving active treatment for unspecified injury of popliteal artery, unspecified leg, such as an emergency visit or first evaluation.

What MS-DRG does S85.009A group to?

When unspecified injury of popliteal artery, unspecified leg, initial encounter is the principal diagnosis on an inpatient stay, it groups to MS-DRG 964, 965, 914, 913, 963, with relative weights from 0.9281 to 2.6361 depending on complications. Higher weights mean higher Medicare reimbursement.

Is S85.009A a CC or MCC?

CMS lists S85.009A as an MCC (major complication or comorbidity) for FY 2027. Reported as a secondary diagnosis, it places the inpatient stay in the highest-weighted DRG of its severity family. It does not count when the principal diagnosis is one of the 90 closely related codes in its exclusion list.

What is the ICD-9 equivalent of S85.009A?

Under the General Equivalence Mappings, unspecified injury of popliteal artery, unspecified leg, initial encounter converts to ICD-9-CM 904.41 (injury popliteal artery). The mapping is approximate, so confirm the match fits the documentation.