2027 ICD-10-CM Diagnosis Code S34.3XXAInjury of cauda equina, initial encounter

ICD-10-CM Codes›S00–T88›S30-S39›S34

ICD-10-CM S34.3XXA
CMSSource: CMS FY 2027 ICD-10-CM dataset · Effective Oct 1, 2026 – Sep 30, 2027

S34.3XXA is a billable ICD-10-CM diagnosis code for injury of cauda equina, 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 52 through 53, 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 363 closely related codes. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Spinal cord injury (SCI), initial encounter.

For Medicare Advantage risk adjustment, S34.3XXA maps to CMS-HCC Category 182 (Spinal Cord Disorders/Injuries) under the V28 model, adding a risk factor of about 0.478 for a community, non-dual, aged beneficiary in payment year 2027.

Code Identity

ICD-10-CM Code
S34.3XXA
Billable Status
Yes — Valid for Submission
Code Describes
Injury of cauda equina, initial encounter
Short Description
Injury of cauda equina, initial encounter
Same as the full description in the CMS dataset.
Parent Code
S34.3
Injury of cauda equina

Code Classification

ChapterS00–T88Injury, poisoning and certain other consequences of external causes
SectionS30-S39Injuries to the abdomen, lower back, lumbar spine, pelvis and external genitals
CategoryS34Injury of lumbar and sacral spinal cord and nerves at abdomen, lower back and pelvis level
This CodeS34.3XXAInjury of cauda equina, initial encounter

Medicare Risk Adjustment (HCC)Billing

S34.3XXA 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 182— Spinal Cord Disorders/Injuries
Payment HCC · PY 2027 one of 251 ICD-10-CM codes in this category
Risk Adjustment Factor (RAF) Weight
+0.478
community, non-dual, aged · ranges 0.270–0.478 across segments
Hierarchy
Superseded by HCC 180, HCC 181, HCC 191, and HCC 192
a more severe related category takes the payment when both are reported
Prior Model (CMS-HCC V24)
HCC 72
V24 retired V28 pays 100% of MA risk scores since PY 2026
Other CMS Models
PACE (CMS-HCC V22): HCC 72 · ESRD (V21): HCC 72 · ESRD (V24): HCC 72
ESRD V21 weights: 0.102 dialysis, 0.256–0.456 functioning graft · ESRD V24 weights: 0.099 dialysis, 0.222–0.523 functioning graft
Part D (RxHCC)
Not mapped
S34.3XXA 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.

  • Cauda equina injury without spinal bone injury
  • Closed fracture of sacrum AND/OR coccyx with cauda equina injury
  • Closed fracture of sacrum AND/OR coccyx with complete cauda equina lesion
  • Closed fracture of sacrum with complete cauda equina lesion
  • Closed fracture sacrum
  • Closed injury cauda equina
  • Closed spinal dislocation with cauda equina lesion
  • Closed spinal fracture with cauda equina lesion
  • Closed spinal subluxation with cauda equina lesion
  • Closed subluxation lumbar spine
  • Injury of cauda equina
  • Open fracture of sacrum AND/OR coccyx with cauda equina injury
  • Open fracture of sacrum AND/OR coccyx with complete cauda equina lesion
  • Open fracture of sacrum with complete cauda equina lesion
  • Open fracture sacrum
  • Open injury cauda equina
  • Open spinal dislocation with cauda equina lesion
  • Open spinal fracture with cauda equina lesion
  • Open spinal subluxation with cauda equina lesion
  • Spinal subluxation with cauda equina lesion

Coding GuidelinesGuidance

The appropriate 7th character is to be added to each code from block Injury of lumbar and sacral spinal cord and nerves at abdomen, lower back and pelvis level (S34). 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 S34.3XXA: its own notes plus those printed at S34, block S30-S39, and Chapter 19. A note printed at a category, block or chapter applies to every code under it.

Includes

Further defines, or gives examples of, the content of the category.

From Block S30-S39 Injuries to the abdomen, lower back, lumbar spine, pelvis and external genitals applies to 2,679 codes
  • injuries to the abdominal wall
  • injuries to the anus
  • injuries to the buttock
  • injuries to the external genitalia
  • injuries to the flank
  • injuries to the groin

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 S30-S39 Injuries to the abdomen, lower back, lumbar spine, pelvis and external genitals applies to 2,679 codes
  • burns and corrosions (T20-T32)
  • effects of foreign body in anus and rectum (T18.5)
  • effects of foreign body in genitourinary tract (T19.-)
  • effects of foreign body in stomach, small intestine and colon (T18.2-T18.4)
  • 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.-)

Code Also

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

From S34 Injury of lumbar and sacral spinal cord and nerves at abdomen, lower back and pelvis level applies to 93 codes
  • any associated:
  • fracture of vertebra (S22.0-, S32.0-)
  • open wound of abdomen, lower back and pelvis (S31.-)
  • transient paralysis (R29.5)

Notes

General instructions on how these codes are used.

From S34 Injury of lumbar and sacral spinal cord and nerves at abdomen, lower back and pelvis level applies to 93 codes
  • Code to highest level of lumbar cord injury
  • Injuries to the spinal cord (S34.0 and S34.1) refer to the cord level and not bone level injury, and can affect nerve roots at and below the level given.
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 S34 Injury of lumbar and sacral spinal cord and nerves at abdomen, lower back and pelvis level applies to 93 codes
  • The appropriate 7th character is to be added to each code from category S34
Values for category S34 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 S34.3XXA, its category, or a range that includes it.

Excludes1 1

These codes carry an Excludes1 note naming S34.3XXA: they are not reported together with it, unless the two conditions are unrelated.

  • G83.8 Other specified paralytic syndromes
    paralytic syndromes due to current spinal cord injury-code to spinal cord injury (S14, S24, S34) names S34, which includes this code

Code First 1

These codes say to code first a condition named in the note, and S34.3XXA is one of the conditions named.

  • S32 Fracture of lumbar spine and pelvis
    any associated spinal cord and spinal nerve injury (S34.-) names S34.-, which includes this code

Clinical ClassificationClinical

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

CCSR INJ009
Spinal cord injury (SCI), initial encounter
Default principal diagnosis: inpatient Yes · outpatient Yes

Patient EducationClinical

Peripheral Nerve Disorders

Nerves are like wires that carry messages back and forth between your brain and your body. Your peripheral nerves branch off from your brain and spinal cord and connect to all parts of your body, including your muscles and organs.

The full article covers:

  • What are peripheral nerves?
  • What are peripheral nerve disorders?
  • What causes peripheral nerve disorders?
  • What are the symptoms of peripheral nerve disorders?
  • How are peripheral nerve disorders diagnosed?
  • What are the treatments for peripheral nerve disorders?
  • Can peripheral nerve disorders be prevented?

Read the full article at MedlinePlus

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

Convert S34.3XXA to ICD-9-CMHistory

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

ICD-9-CM
952.4 Cauda equina injury
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 S34.3XXAOverview

What is the ICD-10 code for injury of cauda equina, initial encounter?

The ICD-10-CM code for injury of cauda equina, initial encounter is S34.3XXA (sometimes written as S343XXA). It is billable on HIPAA-covered claims from October 1, 2026 through September 30, 2027.

Is S34.3XXA (Injury of cauda equina) a billable code?

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

What does the 7th character A in S34.3XXA mean?

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

What MS-DRG does S34.3XXA group to?

When injury of cauda equina, initial encounter is the principal diagnosis on an inpatient stay, it groups to MS-DRG 964, 965, 53, 963, 52, with relative weights from 0.9723 to 2.6361 depending on complications. Higher weights mean higher Medicare reimbursement.

Is S34.3XXA a CC or MCC?

CMS lists S34.3XXA 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 363 closely related codes in its exclusion list.

What HCC is S34.3XXA?

S34.3XXA (injury of cauda equina, initial encounter) maps to CMS-HCC Category 182 (Spinal Cord Disorders/Injuries), commonly written as HCC 182, in the CMS-HCC V28 model used for Medicare Advantage risk adjustment in payment year 2027. It mapped to HCC 72 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 S34.3XXA risk-adjust for Medicare Advantage payment?

Yes. When documented and reported on a Medicare Advantage encounter, S34.3XXA adds a risk adjustment factor of about 0.478 to the beneficiary's RAF score for a community, non-dual, aged enrollee (published V28 weights range from 0.270 to 0.478 depending on the payment segment). A more severe related category (HCC 180, HCC 181, HCC 191, and HCC 192) supersedes it when both are reported. See the full factor table on the HCC 182 category page.