2026 ICD-10-CM Diagnosis Code S29.9XXSUnspecified injury of thorax, sequela
S29.9XXS is a billable ICD-10-CM diagnosis code for unspecified injury of thorax, sequela. The 7th character S marks it as a sequela code, which reports a problem that remains after the original condition has resolved. It is valid on HIPAA claims for fiscal year 2026 (October 1, 2025 through September 30, 2026) and groups to MS-DRG 913 through 914. The code is exempt from POA reporting. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Injury, sequela.
Code Identity
Code Classification
Present on Admission (POA)Billing
S29.9XXS 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.
- Blunt injury
- Blunt injury of thorax
- Breast hematoma
- Central cord syndrome of thoracic spinal cord due to traumatic injury
- Chest injury
- Clavicle injury
- Costal cartilage injury
- Deceleration injury of thorax
- Injury of back of chest
- Injury of breast
- Injury of chest wall
- Injury of front of chest
- Injury of interscapular region
- Injury of left breast
- Injury of ribs
- Injury of right breast
- Injury of side of chest
- Injury of sternum
- Injury of thoracic cavity
- Internal injury of chest, abdomen and pelvis
- Multiple injuries of head and chest
- Multiple injuries of thorax
- Traumatic hematoma of breast
- Traumatic injury of chest wall
- Traumatic injury of posterior chest wall
Coding GuidelinesGuidance
The appropriate 7th character is to be added to each code from block Other and unspecified injuries of thorax (S29). 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 2026, published by CMS and the National Center for Health Statistics.
Clinical ClassificationClinical
AHRQ’s CCSR groups this code into broader clinical categories.
Patient EducationClinical
Chest Injuries and Disorders
The chest is the part of your body between your neck and your abdomen (belly). The medical term for your chest is thorax.
The full article covers:
- What is the chest?
- What are chest injuries and disorders?
- How are chest injuries and disorders diagnosed?
Read the full article at MedlinePlus
Courtesy of MedlinePlus, a service of the U.S. National Library of Medicine.
Convert S29.9XXS to ICD-9-CMHistory
The closest ICD-9-CM equivalents under the General Equivalence Mappings.
Code HistoryHistory
Questions About S29.9XXSOverview
Is S29.9XXS (Unspecified injury of thorax) a billable code?
Yes. This is a billable ICD-10-CM code, specific enough to report unspecified injury of thorax, sequela on HIPAA-covered claims from October 1, 2025 through September 30, 2026.
What does the 7th character S in S29.9XXS mean?
The final character S makes this a sequela code: it reports a lingering problem that remains after the unspecified injury of thorax itself has resolved, not the original event.
What MS-DRG does S29.9XXS group to?
When unspecified injury of thorax, sequela is the principal diagnosis on an inpatient stay, it groups to MS-DRG 913, 914, with relative weights from 0.8855 to 1.6346 depending on complications. Higher weights mean higher Medicare reimbursement.
Is S29.9XXS 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 unspecified injury of thorax, sequela on inpatient claims.
What is the ICD-9 equivalent of S29.9XXS?
Under the General Equivalence Mappings, unspecified injury of thorax, sequela converts to ICD-9-CM 908.9 (late effect injury NOS). 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.
