2026 ICD-10-CM Diagnosis Code S12.130BUnspecified traumatic displaced spondylolisthesis of second cervical vertebra, initial encounter for open fracture
ICD-10-CM Codes›S00–T88›S10-S19›S12
- Billable — Valid for Submission
- MCC — Major Complication or Comorbidity
- Risk Adjusts — HCC 401
- 7th Character B — Initial, Open Fracture
- Not Chronic
S12.130B is a billable ICD-10-CM diagnosis code for unspecified traumatic displaced spondylolisthesis of second cervical vertebra, initial encounter for open fracture. The 7th character B reports the initial encounter for an open fracture. It is valid on HIPAA claims for fiscal year 2026 (October 1, 2025 through September 30, 2026) and groups to MS-DRG 551 through 552, 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 581 closely related codes. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Fracture of the spine and back, initial encounter.
For Medicare Advantage risk adjustment, S12.130B maps to CMS-HCC Category 401 (Vertebral Fractures without Spinal Cord Injury) under the V28 model, adding a risk factor of about 0.522 for a community, non-dual, aged beneficiary in payment year 2026.
Code Identity
Code Classification
Quality Payment Program MeasuresBilling
Medicare quality measures that can apply when S12.130B is part of the patient record.
Communication with the Physician or Other Clinician Managing On-Going Care Post-Fracture for Men and Women Aged 50 Years and Older
High Priority: YES
Measure Type: Process
Submission Methods: Claims, Registry
Description: Percentage of patients aged 50 years and older treated for a fracture with documentation of communication, between the physician treating the fracture and the physician or other clinician managing the patient's on-going care, that a fracture occurred and that the patient was or should be considered for osteoporosis treatment or testing. This measure is submitted by the physician who treats the fracture and who therefore is held accountable for the communication.
Osteoporosis Management in Women Who Had a Fracture
High Priority: NO
Measure Type: Process
Submission Methods: Claims, Registry
Description: The percentage of women 50-85 years of age who suffered a fracture and who had either a bone mineral density (BMD) test or prescription for a drug to treat osteoporosis in the six months after the fracture.
Medicare Risk Adjustment (HCC)Billing
S12.130B 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 2026.
Source: CMS Payment Year 2026 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.
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.
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 S12.130B to ICD-9-CMHistory
The closest ICD-9-CM equivalents under the General Equivalence Mappings.
Code HistoryHistory
Questions About S12.130BOverview
Is S12.130B a billable code?
Yes. This is a billable ICD-10-CM code, specific enough to report unspecified traumatic displaced spondylolisthesis of second cervical vertebra, initial encounter for open fracture on HIPAA-covered claims from October 1, 2025 through September 30, 2026.
What does the 7th character B in S12.130B mean?
The final character B reports the initial encounter for an open fracture, in this case involving the unspecified traumatic displaced spondylolisthesis of second cervical vertebra.
What MS-DRG does S12.130B group to?
When unspecified traumatic displaced spondylolisthesis of second cervical vertebra, initial encounter for open fracture is the principal diagnosis on an inpatient stay, it groups to MS-DRG 551, 552, 963, 964, 965, with relative weights from 0.9405 to 2.7338 depending on complications. Higher weights mean higher Medicare reimbursement.
Is S12.130B a CC or MCC?
CMS lists S12.130B as an MCC (major complication or comorbidity) for FY 2026. 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 581 closely related codes in its exclusion list.
What is the ICD-9 equivalent of S12.130B?
Under the General Equivalence Mappings, unspecified traumatic displaced spondylolisthesis of second cervical vertebra, initial encounter for open fracture converts to ICD-9-CM 805.12 (fx c2 vertebra-open). The mapping is approximate, so confirm the match fits the documentation.
What HCC is S12.130B?
S12.130B (unspecified traumatic displaced spondylolisthesis of second cervical vertebra, initial encounter for open fracture) maps to CMS-HCC Category 401 (Vertebral Fractures without Spinal Cord Injury), commonly written as HCC 401, in the CMS-HCC V28 model used for Medicare Advantage risk adjustment in payment year 2026. It mapped to HCC 169 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 S12.130B risk-adjust for Medicare Advantage payment?
Yes. When documented and reported on a Medicare Advantage encounter, S12.130B adds a risk adjustment factor of about 0.522 to the beneficiary's RAF score for a community, non-dual, aged enrollee (published V28 weights range from 0.231 to 0.622 depending on the payment segment). HCC 401 sits at the top of its hierarchy, so no other condition category supersedes it. See the full factor table on the HCC 401 category page.
