2027 ICD-10-CM Diagnosis Code S98.011AComplete traumatic amputation of right foot at ankle level, initial encounter

ICD-10-CM Codes›S00–T88›S90-S99›S98

ICD-10-CM S98.011A
CMSSource: CMS FY 2027 ICD-10-CM dataset · Effective Oct 1, 2026 – Sep 30, 2027

S98.011A is a billable ICD-10-CM diagnosis code for complete traumatic amputation of right foot at ankle level, 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 complication or comorbidity (CC) and moves an inpatient stay to a higher severity level within its MS-DRG family. It does not count, however, when the principal diagnosis is one of 229 closely related codes. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Amputation of a limb, initial encounter.

For Medicare Advantage risk adjustment, S98.011A maps to CMS-HCC Category 405 (Traumatic Amputations and Complications) under the V28 model, adding a risk factor of about 0.598 for a community, non-dual, aged beneficiary in payment year 2027.

Code Identity

ICD-10-CM Code
S98.011A
Billable Status
Yes — Valid for Submission
Code Describes
Complete traumatic amputation of right foot at ankle level, initial encounter
Short Description
Complete traumatic amp of right foot at ankle level, init
Parent Code
Complete traumatic amputation of right foot at ankle level

Code Classification

ChapterS00–T88Injury, poisoning and certain other consequences of external causes
SectionS90-S99Injuries to the ankle and foot
CategoryS98Traumatic amputation of ankle and foot
This CodeS98.011AComplete traumatic amputation of right foot at ankle level, initial encounter

Medicare Risk Adjustment (HCC)Billing

S98.011A maps to a payment category in the CMS-HCC model used to risk-adjust Medicare Advantage payments. Weights are the published community factors for payment year 2027.

CMS-HCC V28 Category (Payment Model)
HCC 405— Traumatic Amputations and Complications
Payment HCC · PY 2027 one of 108 ICD-10-CM codes in this category
Risk Adjustment Factor (RAF) Weight
+0.598
community, non-dual, aged · ranges 0.284–0.844 across segments
Hierarchy
Supersedes HCC 409
less severe related categories are not paid alongside HCC 405
Prior Model (CMS-HCC V24)
HCC 173
V24 retired V28 pays 100% of MA risk scores since PY 2026
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
S98.011A 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.

Coding GuidelinesGuidance

The appropriate 7th character is to be added to each code from block Traumatic amputation of ankle and foot (S98). 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 S98.011A: its own notes plus those printed at S98, block S90-S99, 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 Block S90-S99 Injuries to the ankle and foot applies to 3,324 codes
  • burns and corrosions (T20-T32)
  • fracture of ankle and malleolus (S82.-)
  • frostbite (T33-T34)
  • 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.-)

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 S98 Traumatic amputation of ankle and foot applies to 108 codes
  • The appropriate 7th character is to be added to each code from category S98
  • 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 S98.011A, its category, or a range that includes it.

Excludes1 2

These codes carry an Excludes1 note naming S98.011A: they are not reported together with it, unless the two conditions are unrelated.

  • S88 Traumatic amputation of lower leg
    traumatic amputation of ankle and foot (S98.-) names S98.-, which includes this code
  • S91 Open wound of ankle, foot and toes
    traumatic amputation of ankle and foot (S98.-) names S98.-, which includes this code

Excludes2 1

These codes carry an Excludes2 note naming S98.011A: its condition is not part of those codes, and both may be reported when the patient has both.

  • S92 Fracture of foot and toe, except ankle
    traumatic amputation of ankle and foot (S98.-) names S98.-, which includes this code

Clinical ClassificationClinical

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

CCSR INJ014
Amputation of a limb, initial encounter
Default principal diagnosis: inpatient Yes · outpatient Yes

Patient EducationClinical

Limb Loss

People can lose all or part of an arm or leg for many reasons. Common ones include:

Read the full article at MedlinePlus

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

Convert S98.011A to ICD-9-CMHistory

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

ICD-9-CM
896.0 Amputation foot, unilat
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 S98.011AOverview

Is S98.011A (Complete traumatic amputation of right foot at ankle level) a billable code?

Yes. This is a billable ICD-10-CM code, specific enough to report complete traumatic amputation of right foot at ankle level, initial encounter on HIPAA-covered claims from October 1, 2026 through September 30, 2027.

What does the 7th character A in S98.011A mean?

The final character A marks the initial encounter: use it while the patient is receiving active treatment for complete traumatic amputation of right foot at ankle level, such as an emergency visit or first evaluation.

What MS-DRG does S98.011A group to?

When complete traumatic amputation of right foot at ankle level, 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 S98.011A a CC or MCC?

CMS lists S98.011A as a CC (complication or comorbidity) for FY 2027. Reported as a secondary diagnosis, it moves the inpatient stay to a higher-weighted DRG within its severity family. It does not count when the principal diagnosis is one of the 229 closely related codes in its exclusion list.

What is the ICD-9 equivalent of S98.011A?

Under the General Equivalence Mappings, complete traumatic amputation of right foot at ankle level, initial encounter converts to ICD-9-CM 896.0 (amputation foot, unilat). The mapping is approximate, so confirm the match fits the documentation.

What HCC is S98.011A?

S98.011A (complete traumatic amputation of right foot at ankle level, initial encounter) maps to CMS-HCC Category 405 (Traumatic Amputations and Complications), commonly written as HCC 405, in the CMS-HCC V28 model used for Medicare Advantage risk adjustment in payment year 2027. It mapped to HCC 173 under the retired V24 model. It also maps in the PACE (CMS-HCC V22), ESRD (V21), and ESRD (V24) models. It does not map to any RxHCC in the Part D prescription drug model.

Does S98.011A risk-adjust for Medicare Advantage payment?

Yes. When documented and reported on a Medicare Advantage encounter, S98.011A adds a risk adjustment factor of about 0.598 to the beneficiary's RAF score for a community, non-dual, aged enrollee (published V28 weights range from 0.284 to 0.844 depending on the payment segment). HCC 405 sits at the top of its hierarchy, so no other condition category supersedes it. See the full factor table on the HCC 405 category page.