2027 ICD-10-CM Diagnosis Code S22.5XXAFlail chest, initial encounter for closed fracture
ICD-10-CM Codes›S00–T88›S20-S29›s
- Billable — Valid for Submission
- MCC — Major Complication or Comorbidity
- 7th Character A — Initial Encounter for Closed Fracture
- Not Chronic
S22.5XXA is a billable ICD-10-CM diagnosis code for flail chest, 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 183 through 185, 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 54 closely related codes. Coders also document this condition as closed flail chest. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Fracture of torso, initial encounter.
Code Identity
Code Classification
Quality Payment Program MeasuresBilling
Medicare quality measures that can apply when S22.5XXA 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 180 days after the fracture.
Approximate SynonymsGuidance
Alternate terms and clinical phrases that map to this code.
- Closed flail chest
- Flail chest
- Flail sternum
- Open flail chest
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 S22.5XXA: its own notes plus those printed at S22, block S20-S29, 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.
- fracture of thoracic neural arch
- fracture of thoracic spinous process
- fracture of thoracic transverse process
- fracture of thoracic vertebra
- fracture of thoracic vertebral arch
- injuries of breast
- injuries of chest (wall)
- injuries of interscapular area
Excludes1
Not coded here: the excluded code is never reported together with this one, unless the two conditions are unrelated.
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.
- burns and corrosions (T20-T32)
- effects of foreign body in bronchus (T17.5)
- effects of foreign body in esophagus (T18.1)
- effects of foreign body in lung (T17.8)
- effects of foreign body in trachea (T17.4)
- frostbite (T33-T34)
- injuries of axilla
- injuries of clavicle
- injuries of scapular region
- injuries of shoulder
- insect bite or sting, venomous (T63.4)
Code First
The underlying condition named in the note is sequenced before this code.
Use Additional Code
Add a second code, after this one, to fully describe the condition.
- 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.
Notes
General instructions on how these codes are used.
- 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
- 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.
- The appropriate 7th character is to be added to each code from category S22
- 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 S22.5XXA, its category, or a range that includes it.
Excludes1 5
These codes carry an Excludes1 note naming S22.5XXA: they are not reported together with it, unless the two conditions are unrelated.
- M48.5 Collapsed vertebra, not elsewhere classifiedtraumatic fracture of vertebra (S12.-, S22.-, S32.-) names S22.-, which includes this code
- M84.3 Stress fracturetraumatic fracture (S12.-, S22.-, S32.-, S42.-, S52.-, S62.-, S72.-, S82.-, S92.-) names S22.-, which includes this code
- M84.4 Pathological fracture, not elsewhere classifiedtraumatic fracture (S12.-, S22.-, S32.-, S42.-, S52.-, S62.-, S72.-, S82.-, S92.-) names S22.-, which includes this code
- S22.4 Multiple fractures of ribsflail chest (S22.5-) names S22.5-, which includes this code
- S28.0 Crushed chestflail chest (S22.5) names S22.5, which includes this code
Clinical ClassificationClinical
AHRQ’s CCSR groups this code into broader clinical categories.
Clinical InformationClinical
Flail Chest
a complication of multiple rib fractures; rib and sternum fractures, or thoracic surgery. a portion of the thoracic wall becomes isolated from the rib cage and exhibits paradoxical respiration.
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 S22.5XXA to ICD-9-CMHistory
The closest ICD-9-CM equivalents under the General Equivalence Mappings.
Code HistoryHistory
Questions About S22.5XXAOverview
What is the ICD-10 code for flail chest, initial encounter for closed fracture?
The ICD-10-CM code for flail chest, initial encounter for closed fracture is S22.5XXA (sometimes written as S225XXA). It is billable on HIPAA-covered claims from October 1, 2026 through September 30, 2027.
Is S22.5XXA (Flail chest) a billable code?
Yes. This is a billable ICD-10-CM code, specific enough to report flail chest, initial encounter for closed fracture on HIPAA-covered claims from October 1, 2026 through September 30, 2027.
What does the 7th character A in S22.5XXA mean?
The final character A marks the initial encounter: use it while the patient is receiving active treatment for flail chest, 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 S22.5XXA group to?
When flail chest, initial encounter for closed fracture is the principal diagnosis on an inpatient stay, it groups to MS-DRG 964, 965, 185, 183, 963, 184, with relative weights from 0.7712 to 2.6361 depending on complications. Higher weights mean higher Medicare reimbursement.
Is S22.5XXA a CC or MCC?
CMS lists S22.5XXA as an MCC (major complication or comorbidity) for FY 2027. 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 54 closely related codes in its exclusion list.
