2026 ICD-10-CM Diagnosis Code S13.170SSubluxation of C6/C7 cervical vertebrae, sequela
S13.170S is a billable ICD-10-CM diagnosis code for subluxation of C6/C7 cervical vertebrae, 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 562 through 563. The code is exempt from POA reporting. Coders also document this condition as closed dislocation C6/C7. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Injury, sequela.
Code Identity
Code Classification
Present on Admission (POA)Billing
S13.170S 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 dislocation C6/C7
- Closed subluxation C6/C7
- Open dislocation C6/C7
- Open dislocation of seventh cervical vertebra
- Open dislocation of sixth cervical vertebra
- Open subluxation C6/C7
- Traumatic dislocation of sixth and seventh cervical vertebra
Coding GuidelinesGuidance
The appropriate 7th character is to be added to each code from block Dislocation and sprain of joints and ligaments at neck level (S13). 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
Dislocations
Dislocations are joint injuries that force the ends of your bones out of position. The cause is often a fall or a blow, sometimes from playing a contact sport. You can dislocate your ankles, knees, shoulders, hips, elbows and jaw. You can also dislocate your finger and toe joints.
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Convert S13.170S to ICD-9-CMHistory
The closest ICD-9-CM equivalents under the General Equivalence Mappings.
Code HistoryHistory
Questions About S13.170SOverview
Is S13.170S (Subluxation of C6/C7 cervical vertebrae) a billable code?
Yes. This is a billable ICD-10-CM code, specific enough to report subluxation of C6/C7 cervical vertebrae, sequela on HIPAA-covered claims from October 1, 2025 through September 30, 2026.
What does the 7th character S in S13.170S mean?
The final character S makes this a sequela code: it reports a lingering problem that remains after the subluxation of C6/C7 cervical vertebrae itself has resolved, not the original event.
What MS-DRG does S13.170S group to?
When subluxation of C6/C7 cervical vertebrae, sequela is the principal diagnosis on an inpatient stay, it groups to MS-DRG 562, 563, with relative weights from 0.8955 to 1.4248 depending on complications. Higher weights mean higher Medicare reimbursement.
Is S13.170S 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 subluxation of C6/C7 cervical vertebrae, sequela on inpatient claims.
What is the ICD-9 equivalent of S13.170S?
Under the General Equivalence Mappings, subluxation of C6/C7 cervical vertebrae, sequela converts to ICD-9-CM 905.6 (late effect dislocation). 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.
