S12.291K
Other nondisplaced fracture of third cervical vertebra, subsequent encounter for fracture with nonunion
S12.291K (also written S12291K) is a billable ICD-10-CM diagnosis code for other nondisplaced fracture of third cervical vertebra, subsequent encounter for fracture with nonunion. It is part of the FY2027 code set, effective October 1, 2026. It is one of the 420 codes in category S12 (Fracture of cervical vertebra and other parts of neck). The Alphabetic Index lists it under 1 entry. Its 7th character, K, means subsequent encounter for fracture with nonunion. Its coding notes include a Code first instruction, a Use additional code instruction and 9 Excludes2 entries.
7th character
Category S12 requires a 7th character.
Guidelines tips
From the FY2027 Official Guidelines. ICD10Ref adds no rules of its own.
A fracture not stated as open or closed is coded closed, and one not stated as displaced or not displaced is coded displaced. Nonunion and malunion have their own 7th characters.
The 7th character depends on whether the patient is in active treatment, not on who sees the patient. An aftercare Z code is not used for injury aftercare.
Each injury gets its own code unless a combination code exists, with the most serious injury first. Superficial injuries at the same site as a more severe injury are not coded. Injuries during medical care are coded as complications.
Code first
If the underlying condition listed here is present and known, sequence it first.
Use additional code
Add the listed code as a secondary code, if known.
Also from chapter/block level (1 note)
- code to identify any retained foreign body, if applicable (Z18.-)
Excludes2
Not included here. Both codes may be reported if the patient has both conditions.
Also from chapter/block level (9 notes)
- birth trauma (P10-P15)
- obstetric trauma (O70-O71)
Care settings
How CMS programs treat this code. These are CMS claim edits and list entries, not coverage or eligibility rules.
Home Health Primary
Accepted as the primary (principal) diagnosis on a home health claim. The Home Health Grouper assigns it to the Musculoskeletal Rehabilitation clinical group.
Source: CMS Home Health Grouper Software v07.2.26, effective October 1, 2026Hospital CC
Counts as a complication or comorbidity (CC) when reported as a secondary diagnosis on an inpatient claim. It does not count when the principal diagnosis is one of the 5,561 codes in its exclusion list. Some MS-DRGs also ignore a CC or MCC that defines the DRG.
Source: CMS MS-DRG Definitions Manual v44, effective October 1, 2026, Appendix CIncludes
Further defines or gives examples of the content of the category.
- fracture of cervical neural arch
- fracture of cervical spine
- fracture of cervical spinous process
- fracture of cervical transverse process
- fracture of cervical vertebral arch
- fracture of neck
Also from chapter/block level (3 notes)
- injuries of nape
- injuries of supraclavicular region
- injuries of throat
Notes
- A fracture not indicated as displaced or nondisplaced should be coded to displaced
- A fracture not indicated as open or closed should be coded to closed
Also from chapter/block level (2 notes)
- Use secondary code(s) from Chapter 20, External causes of morbidity, to indicate cause of injury. Codes within the T section that include the external cause do not require an additional external cause code
- The chapter uses the S-section for coding different types of injuries related to single body regions and the T-section to cover injuries to unspecified body regions as well as poisoning and certain other consequences of external causes.
Alphabetic Index terms
Terms the official Alphabetic Index lists for S12.291. This code adds the 7th character. 1 entry