2026 ICD-10-CM Diagnosis Code S32.413KDisplaced fracture of anterior wall of unspecified acetabulum, subsequent encounter for fracture with nonunion

ICD-10-CM Codes›S00–T88›S30-S39›S32

ICD-10-CM S32.413K
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

S32.413K is a billable ICD-10-CM diagnosis code for displaced fracture of anterior wall of unspecified acetabulum, subsequent encounter for fracture with nonunion. The 7th character K reports a subsequent encounter for a fracture that has failed to heal, called a nonunion. It is valid on HIPAA claims for fiscal year 2026 (October 1, 2025 through September 30, 2026) and groups to MS-DRG 521 through 522, 564 through 566. The code is flagged as an unspecified code, since codes identifying laterality exist in the same family and exempt from POA reporting. Coders also document this condition as closed fracture acetabulum, anterior column. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Fracture of torso, subsequent encounter.

Code Identity

ICD-10-CM Code
S32.413K
Billable Status
Yes — Valid for Submission
Code Describes
Displaced fracture of anterior wall of unspecified acetabulum, subsequent encounter for fracture with nonunion
Short Description
Disp fx of ant wall of unsp acetab, subs for fx w nonunion
Parent Code
S32.413
Displaced fracture of anterior wall of unspecified acetabulum

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
CategoryS32Fracture of lumbar spine and pelvis
This CodeS32.413KDisplaced fracture of anterior wall of unspecified acetabulum, subsequent encounter for fracture with nonunion

Code EditsBilling

Medicare Code Editor checks that affect claim validity for S32.413K.

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.

Present on Admission (POA)Billing

S32.413K is exempt from POA reporting on inpatient claims to general acute care hospitals. Review other POA exempt codes.

Approximate SynonymsGuidance

Alternate terms and clinical phrases that map to this code.

  • Closed fracture acetabulum, anterior column
  • Closed fracture of anterior wall of acetabulum
  • Open fracture acetabulum, anterior column
  • Open fracture of anterior wall of acetabulum

Coding GuidelinesGuidance

The principles of multiple coding of injuries should be followed in coding fractures. Fractures of specified sites are coded individually by site, to the level of detail furnished by medical record content.

A fracture not indicated as open or closed should be coded to closed. A fracture not indicated whether displaced or not displaced should be coded to displaced.

Initial vs. Subsequent Encounter for Fractures

Traumatic fractures are coded using the appropriate 7th character for initial encounter (A, B, C) while the patient is receiving active treatment for the fracture. The appropriate 7th character for initial encounter should also be assigned for a patient who delayed seeking treatment for the fracture or nonunion.

Fractures are coded using the appropriate 7th character for subsequent care for encounters after the patient has completed active treatment of the fracture and is receiving routine care for the fracture during the healing or recovery phase.

Care for complications of surgical treatment for fracture repairs during the healing or recovery phase should be coded with the appropriate complication codes.

Care of complications of fractures, such as malunion and nonunion, should be reported with the appropriate 7th character for subsequent care with nonunion (K, M, N) or subsequent care with malunion (P, Q, R).

The open fracture designations in the assignment of the 7th character for fractures of the forearm, femur and lower leg, including ankle are based on the Gustilo open fracture classification. When the Gustilo classification type is not specified for an open fracture, the 7th character for open fracture type I or II should be assigned (B, E, H, M, Q).

Source: ICD-10-CM Official Guidelines for Coding and Reporting, FY 2026, published by CMS and the National Center for Health Statistics.

Clinical ClassificationClinical

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

CCSR INJ040
Fracture of torso, subsequent encounter
Default principal diagnosis: inpatient Yes · outpatient Yes

Patient EducationClinical

Fractures

A fracture is a break in a bone. Fractures are usually caused by injuries. Since they can sometimes be serious, it's important to get medical care right away if you think you have a fracture.

The full article covers:

  • What is a fracture?
  • What are the different types of fractures?
  • What causes fractures?
  • What are the symptoms of a fracture?
  • How are fractures diagnosed?
  • What are the treatments for fractures?
  • Can fractures be prevented?

Read the full article at MedlinePlus

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

Convert S32.413K to ICD-9-CMHistory

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

ICD-9-CM
733.82 Nonunion of fracture
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 2017–2025No changes
FY 2026CurrentCurrent code set, no changesEffective October 1, 2025 through September 30, 2026.

Questions About S32.413KOverview

Is S32.413K a billable code?

Yes. This is a billable ICD-10-CM code, specific enough to report displaced fracture of anterior wall of unspecified acetabulum, subsequent encounter for fracture with nonunion on HIPAA-covered claims from October 1, 2025 through September 30, 2026.

What does the 7th character K in S32.413K mean?

The final character K reports a subsequent encounter where the displaced fracture of anterior wall of unspecified acetabulum has failed to heal, called a nonunion.

What MS-DRG does S32.413K group to?

When displaced fracture of anterior wall of unspecified acetabulum, subsequent encounter for fracture with nonunion is the principal diagnosis on an inpatient stay, it groups to MS-DRG 521, 522, 564, 565, 566, with relative weights from 0.7493 to 2.8702 depending on complications. Higher weights mean higher Medicare reimbursement.

Is S32.413K exempt from POA reporting?

Yes. CMS lists this code among those exempt from present on admission reporting, so hospitals do not assign a POA indicator for displaced fracture of anterior wall of unspecified acetabulum, subsequent encounter for fracture with nonunion on inpatient claims.

What is the ICD-9 equivalent of S32.413K?

Under the General Equivalence Mappings, displaced fracture of anterior wall of unspecified acetabulum, subsequent encounter for fracture with nonunion converts to ICD-9-CM 733.82 (nonunion of fracture). The mapping is approximate, so confirm the match fits the documentation.

Footnotes

[1] Not chronic - A diagnosis code that does not fit the criteria for chronic condition (duration, ongoing medical treatment, and limitations) is considered not chronic. Some codes designated as not chronic are acute conditions. Other diagnosis codes that indicate a possible chronic condition, but for which the duration of the illness is not specified in the code description (i.e., we do not know the condition has lasted 12 months or longer) also are considered not chronic.