2027 ICD-10-CM Diagnosis Code S02.121AFracture of orbital roof, right side, initial encounter for closed fracture

ICD-10-CM Codes›S00–T88›S00-S09›S02

ICD-10-CM S02.121A
CMSSource: CMS FY 2027 ICD-10-CM dataset · Effective Oct 1, 2026 – Sep 30, 2027

S02.121A is a billable ICD-10-CM diagnosis code for fracture of orbital roof, right side, initial encounter for closed fracture. The 7th character A means initial encounter for closed fracture, used while the patient is receiving active treatment. It is valid on HIPAA claims for fiscal year 2027 (October 1, 2026 through September 30, 2027) and groups to MS-DRG 82 through 87, 963 through 965. As a secondary diagnosis, it counts as a complication or comorbidity (CC) and moves an inpatient stay to a higher severity level within its MS-DRG family. It does not count, however, when the principal diagnosis is one of 383 closely related codes. Coders also document this condition as closed fracture of right orbit. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Fracture of head and neck, initial encounter.

For Medicare Advantage risk adjustment, S02.121A maps to CMS-HCC Category 399 (Major Head Injury without Loss of Consciousness) under the V28 model, adding a risk factor of about 0.199 for a community, non-dual, aged beneficiary in payment year 2027.

Code Identity

ICD-10-CM Code
S02.121A
Billable Status
Yes — Valid for Submission
Code Describes
Fracture of orbital roof, right side, initial encounter for closed fracture
Short Description
Fracture of orbital roof, right side, init
Parent Code
Fracture of orbital roof, right side

Code Classification

ChapterS00–T88Injury, poisoning and certain other consequences of external causes
SectionS00-S09Injuries to the head
CategoryS02Fracture of skull and facial bones
This CodeS02.121AFracture of orbital roof, right side, initial encounter for closed fracture

Medicare Risk Adjustment (HCC)Billing

S02.121A 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 2027.

CMS-HCC V28 Category (Payment Model)
HCC 399— Major Head Injury without Loss of Consciousness
Payment HCC · PY 2027 one of 189 ICD-10-CM codes in this category
Risk Adjustment Factor (RAF) Weight
+0.199
community, non-dual, aged · ranges 0.052–0.349 across segments
Hierarchy
Superseded by HCC 397 and HCC 398
a more severe related category takes the payment when both are reported
Prior Model (CMS-HCC V24)
HCC 167
V24 retired V28 pays 100% of MA risk scores since PY 2026
Other CMS Models
PACE (CMS-HCC V22): HCC 167 · ESRD (V21): HCC 167 · ESRD (V24): HCC 167
ESRD V21 weights: 0.017 dialysis, 0.000–0.184 functioning graft · ESRD V24 weights: 0.043 dialysis, 0.000–0.239 functioning graft
Part D (RxHCC)
Not mapped
S02.121A does not risk-adjust in the RxHCC prescription drug model

Source: CMS Payment Year 2027 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.

Approximate SynonymsGuidance

Alternate terms and clinical phrases that map to this code.

  • Closed fracture of right orbit
  • Fracture of orbital roof
  • Open fracture of right orbit
  • Open fracture of right orbital roof
  • Open fracture of superior wall of orbit
  • Right superior wall orbit closed fracture

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 2027, published by CMS and the National Center for Health Statistics.

Instructional NotesGuidance

Instructions from the official ICD-10-CM Tabular List that apply to S02.121A: its own notes plus those printed at S02.1, S02, block S00-S09, and Chapter 19. A note printed at a category, block or chapter applies to every code under it.

Includes

Further defines, or gives examples of, the content of the category.

From Block S00-S09 Injuries to the head applies to 1,934 codes
  • injuries of ear
  • injuries of eye
  • injuries of face [any part]
  • injuries of gum
  • injuries of jaw
  • injuries of oral cavity
  • injuries of palate
  • injuries of periocular area
  • injuries of scalp
  • injuries of temporomandibular joint area
  • injuries of tongue
  • injuries of tooth

Excludes2

Not included here: the excluded condition is not part of this code, but a patient may have both, so both codes may be reported.

From S02.1 Fracture of base of skull applies to 126 codes
From Block S00-S09 Injuries to the head applies to 1,934 codes
  • burns and corrosions (T20-T32)
  • effects of foreign body in ear (T16)
  • effects of foreign body in larynx (T17.3)
  • effects of foreign body in mouth NOS (T18.0)
  • effects of foreign body in nose (T17.0-T17.1)
  • effects of foreign body in pharynx (T17.2)
  • effects of foreign body on external eye (T15.-)
  • frostbite (T33-T34)
  • insect bite or sting, venomous (T63.4)
From Chapter 19 (S00-T88) Injury, poisoning and certain other consequences of external causes applies to 41,187 codes

Use Additional Code

Add a second code, after this one, to fully describe the condition.

From Chapter 19 (S00-T88) Injury, poisoning and certain other consequences of external causes applies to 41,187 codes
  • code to identify any retained foreign body, if applicable (Z18.-)

Code Also

A second code may be needed to fully describe the condition; the note gives no sequencing direction.

From S02 Fracture of skull and facial bones applies to 456 codes
  • any associated intracranial injury (S06.-)
From Block S00-S09 Injuries to the head applies to 1,934 codes
  • for any associated infection

Notes

General instructions on how these codes are used.

From S02 Fracture of skull and facial bones applies to 456 codes
  • A fracture not indicated as open or closed should be coded to closed
From Chapter 19 (S00-T88) Injury, poisoning and certain other consequences of external causes applies to 41,187 codes
  • 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.

7th Character

Every code in the category takes a 7th character from the listed values, with the placeholder X filling any empty positions before it.

From S02 Fracture of skull and facial bones applies to 456 codes
  • The appropriate 7th character is to be added to each code from category S02
  • Ainitial encounter for closed fracture this code
  • Binitial encounter for open fracture
  • Dsubsequent encounter for fracture with routine healing
  • Gsubsequent encounter for fracture with delayed healing
  • Ksubsequent encounter for fracture with nonunion
  • Ssequela

Source: CMS ICD-10-CM Tabular List. How to read instructional notes.

Referenced in Other NotesGuidance

Instructional notes printed at other codes that name S02.121A, its category, or a range that includes it.

Excludes1 2

These codes carry an Excludes1 note naming S02.121A: they are not reported together with it, unless the two conditions are unrelated.

  • S01 Open wound of head
    open skull fracture (S02.- with 7th character B) names S02.-, which includes this code
  • S02.85 Fracture of orbit, unspecified
    orbital roof (S02.12-) names S02.12-, which includes this code

Excludes2 5

These codes carry an Excludes2 note naming S02.121A: its condition is not part of those codes, and both may be reported when the patient has both.

  • S02.3 Fracture of orbital floor
    orbital roof (S02.1-) names S02.1-, which includes this code
  • S02.8 Fractures of other specified skull and facial bones
    fracture of orbital roof (S02.12-) names S02.12-, which includes this code
  • S02.83 Fracture of medial orbital wall
    orbital roof (S02.12-) names S02.12-, which includes this code
  • S02.84 Fracture of lateral orbital wall
    orbital roof (S02.12-) names S02.12-, which includes this code
  • S05 Injury of eye and orbit
    orbital bone fracture (S02.1-, S02.3-, S02.8-) names S02.1-, which includes this code

Code First 1

These codes say to code first a condition named in the note, and S02.121A is one of the conditions named.

  • R40.2 Coma
    fracture of skull (S02.-) names S02.-, which includes this code

Use Additional Code 1

These codes say to use an additional code from the note, and S02.121A is one of the codes named.

  • S07 Crushing injury of head
    skull fractures (S02.-) names S02.-, which includes this code

Code Also 2

These codes say S02.121A may also be needed to fully describe the condition. The note gives no sequencing direction.

  • S04 Injury of cranial nerve
    skull fracture (S02.-) names S02.-, which includes this code
  • S06 Intracranial injury
    skull fracture (S02.-) names S02.-, which includes this code

Clinical ClassificationClinical

AHRQ’s CCSR groups this code into broader clinical categories.

CCSR INJ001
Fracture of head and neck, initial encounter
Default principal diagnosis: inpatient Yes · outpatient Yes

Patient EducationClinical

Facial Injuries and Disorders

Face injuries and disorders can cause pain and affect how you look. In severe cases, they can affect sight, speech, breathing and your ability to swallow. Fractures (broken bones), especially in the bones of your nose, cheekbone and jaw, are common facial injuries.

Read the full article at MedlinePlus

Courtesy of MedlinePlus, a service of the U.S. National Library of Medicine.

Code History & ChangesHistory

Replacement S02.121A replaces the following previously assigned code(s):

  • S02.19XA - Oth fracture of base of skull, init for clos fx
FY 2020AddedAdded to the ICD-10-CM code setEffective October 1, 2019.
FY 2021–2026No changes
FY 2027CurrentCurrent code set, no changesEffective October 1, 2026 through September 30, 2027.

Questions About S02.121AOverview

Is S02.121A (Fracture of orbital roof, right side) a billable code?

Yes. This is a billable ICD-10-CM code, specific enough to report fracture of orbital roof, right side, initial encounter for closed fracture on HIPAA-covered claims from October 1, 2026 through September 30, 2027.

What does the 7th character A in S02.121A mean?

The final character A marks the initial encounter: use it while the patient is receiving active treatment for fracture of orbital roof, right side, such as an emergency visit or first evaluation. In this category the CMS Tabular List defines A as "initial encounter for closed fracture".

What MS-DRG does S02.121A group to?

When fracture of orbital roof, right side, initial encounter for closed fracture is the principal diagnosis on an inpatient stay, it groups to MS-DRG 85, 964, 83, 84, 965, 82, 86, 87, 963, with relative weights from 0.9219 to 2.6361 depending on complications. Higher weights mean higher Medicare reimbursement.

Is S02.121A a CC or MCC?

CMS lists S02.121A as a CC (complication or comorbidity) for FY 2027. Reported as a secondary diagnosis, it moves the inpatient stay to a higher-weighted DRG within its severity family. It does not count when the principal diagnosis is one of the 383 closely related codes in its exclusion list.

What HCC is S02.121A?

S02.121A (fracture of orbital roof, right side, initial encounter for closed fracture) maps to CMS-HCC Category 399 (Major Head Injury without Loss of Consciousness), commonly written as HCC 399, in the CMS-HCC V28 model used for Medicare Advantage risk adjustment in payment year 2027. It mapped to HCC 167 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 S02.121A risk-adjust for Medicare Advantage payment?

Yes. When documented and reported on a Medicare Advantage encounter, S02.121A adds a risk adjustment factor of about 0.199 to the beneficiary's RAF score for a community, non-dual, aged enrollee (published V28 weights range from 0.052 to 0.349 depending on the payment segment). A more severe related category (HCC 397 and HCC 398) supersedes it when both are reported. See the full factor table on the HCC 399 category page.