2026 ICD-10-CM Diagnosis Code S02.19XKOther fracture of base of skull, subsequent encounter for fracture with nonunion

ICD-10-CM Codes›S00–T88›S00-S09›S02

ICD-10-CM S02.19XK
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

S02.19XK is a billable ICD-10-CM diagnosis code for other fracture of base of skull, 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 564 through 566. The code is exempt from POA reporting. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Fracture of head and neck, subsequent encounter.

Code Identity

ICD-10-CM Code
S02.19XK
Billable Status
Yes — Valid for Submission
Code Describes
Other fracture of base of skull, subsequent encounter for fracture with nonunion
Short Description
Oth fracture of base of skull, subs for fx w nonunion
Parent Code
S02.19
Other fracture of base of skull

Code Classification

ChapterS00–T88Injury, poisoning and certain other consequences of external causes
SectionS00-S09Injuries to the head
CategoryS02Fracture of skull and facial bones
This CodeS02.19XKOther fracture of base of skull, subsequent encounter for fracture with nonunion

Present on Admission (POA)Billing

S02.19XK 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 of frontal sinus
  • Closed fracture of left naso orbital ethmoid
  • Closed fracture of naso orbital ethmoid
  • Closed fracture of right naso orbital ethmoid
  • Closed fracture of temporal bone
  • Complex fracture of temporal bone
  • Cribriform plate fracture
  • Fracture of anterior fossa
  • Fracture of bone of nasal sinus
  • Fracture of ethmoid bone
  • Fracture of frontal bone
  • Fracture of frontal sinus
  • Fracture of left temporal bone
  • Fracture of medial wall of orbit
  • Fracture of middle fossa
  • Fracture of orbital plate of ethmoid bone
  • Fracture of posterior fossa
  • Fracture of right temporal bone
  • Fracture of sphenoid bone
  • Fracture of squamous part of temporal bone of skull
  • Fracture of temporal bone
  • Longitudinal fracture of temporal bone
  • Open fracture of frontal sinus
  • Open fracture of naso orbital ethmoid
  • Open fracture of temporal bone
  • Open wound of nasal sinus
  • Petrous bone fracture
  • Sphenoid sinus fracture
  • Transverse fracture of temporal bone

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 INJ038
Fracture of head and neck, 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 S02.19XK 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 S02.19XKOverview

Is S02.19XK (Other fracture of base of skull) a billable code?

Yes. This is a billable ICD-10-CM code, specific enough to report other fracture of base of skull, 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 S02.19XK mean?

The final character K reports a subsequent encounter where the other fracture of base of skull has failed to heal, called a nonunion.

What MS-DRG does S02.19XK group to?

When other fracture of base of skull, subsequent encounter for fracture with nonunion is the principal diagnosis on an inpatient stay, it groups to MS-DRG 564, 565, 566, with relative weights from 0.7493 to 1.5436 depending on complications. Higher weights mean higher Medicare reimbursement.

Is S02.19XK 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 other fracture of base of skull, subsequent encounter for fracture with nonunion on inpatient claims.

What is the ICD-9 equivalent of S02.19XK?

Under the General Equivalence Mappings, other fracture of base of skull, 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.