2027 ICD-10-CM Diagnosis Code S21.149APuncture wound with foreign body of unspecified front wall of thorax without penetration into thoracic cavity, initial encounter

ICD-10-CM Codes›S00–T88›S20-S29›S21

ICD-10-CM S21.149A
CMSSource: CMS FY 2027 ICD-10-CM dataset · Effective Oct 1, 2026 – Sep 30, 2027

S21.149A is a billable ICD-10-CM diagnosis code for puncture wound with foreign body of unspecified front wall of thorax without penetration into thoracic cavity, initial encounter. The 7th character A marks it as an initial encounter code, 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 913 through 914, 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 95 closely related codes. The code is flagged as an unspecified code, since codes identifying laterality exist in the same family. Coders also document this condition as fishing hook in chest. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Open wounds of trunk, initial encounter.

Code Identity

ICD-10-CM Code
S21.149A
Billable Status
Yes — Valid for Submission
Code Describes
Puncture wound with foreign body of unspecified front wall of thorax without penetration into thoracic cavity, initial encounter
Short Description
Pnctr w fb of unsp frnt wl of thrx w/o penet thor cav, init
Parent Code
S21.149
Puncture wound with foreign body of unspecified front wall of thorax without penetration into thoracic cavity

Code Classification

ChapterS00–T88Injury, poisoning and certain other consequences of external causes
SectionS20-S29Injuries to the thorax
CategoryS21Open wound of thorax
This CodeS21.149APuncture wound with foreign body of unspecified front wall of thorax without penetration into thoracic cavity, initial encounter

Code EditsBilling

Medicare Code Editor checks that affect claim validity for S21.149A.

Unspecified codes
Unspecified codes exist in the ICD-10-CM classification for circumstances when documentation in the medical record does not provide the level of detail needed to support reporting a more specific code. However, in the inpatient setting, there should generally be very limited and rare circumstances for which the laterality (right, left, bilateral) of a condition is unable to be documented and reported. The following pages contain the list of unspecified ICD-10-CM diagnosis codes for which there is a more specific code to identify laterality (right, left, bilateral) within that code family.

Approximate SynonymsGuidance

Alternate terms and clinical phrases that map to this code.

  • Fishing hook in chest
  • Fishing hook in trunk
  • Pellet wound of chest
  • Pellet wound of trunk

Coding GuidelinesGuidance

The appropriate 7th character is to be added to each code from block Open wound of thorax (S21). 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 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 S21.149A: its own notes plus those printed at S21, 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.

From Block S20-S29 Injuries to the thorax applies to 1,602 codes
  • 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.

From S21 Open wound of thorax applies to 288 codes
  • traumatic amputation (partial) of thorax (S28.1)

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 Block S20-S29 Injuries to the thorax applies to 1,602 codes
  • 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)
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 S21 Open wound of thorax applies to 288 codes
  • any associated injury, such as:
  • injury of heart (S26.-)
  • injury of intrathoracic organs (S27.-)
  • rib fracture (S22.3-, S22.4-)
  • spinal cord injury (S24.0-, S24.1-)
  • traumatic hemopneumothorax (S27.3)
  • traumatic hemothorax (S27.1)
  • traumatic pneumothorax (S27.0)
  • wound infection

Notes

General instructions on how these codes are used.

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 S21 Open wound of thorax applies to 288 codes
  • The appropriate 7th character is to be added to each code from category S21
Values for category S21 Encounter: Initial, Subsequent, Sequela
  • Ainitial encounter this code
  • Dsubsequent encounter
  • 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 S21.149A, its category, or a range that includes it.

Excludes1 1

These codes carry an Excludes1 note naming S21.149A: they are not reported together with it, unless the two conditions are unrelated.

  • S20.37 Other superficial bite of front wall of thorax
    open bite of front wall of thorax (S21.14) names S21.14, which includes this code

Code Also 6

These codes say S21.149A may also be needed to fully describe the condition. The note gives no sequencing direction.

  • S23.1 Subluxation and dislocation of thoracic vertebra
    open wound of thorax (S21.-) names S21.-, which includes this code
  • S24 Injury of nerves and spinal cord at thorax level
    open wound of thorax (S21.-) names S21.-, which includes this code
  • S25 Injury of blood vessels of thorax
    any associated open wound (S21.-) names S21.-, which includes this code
  • S26 Injury of heart
    open wound of thorax (S21.-) names S21.-, which includes this code
  • S27 Injury of other and unspecified intrathoracic organs
    any associated open wound of thorax (S21.-) names S21.-, which includes this code
  • S29 Other and unspecified injuries of thorax
    any associated open wound (S21.-) names S21.-, which includes this code

Clinical ClassificationClinical

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

CCSR INJ013
Open wounds of trunk, initial encounter
Default principal diagnosis: inpatient Yes · outpatient Yes

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 S21.149A to ICD-9-CMHistory

The closest ICD-9-CM equivalents under the General Equivalence Mappings.

ICD-9-CM
875.1 Open wound chest-compl
Approximate The match is approximate rather than exact.

Code HistoryHistory

FY 2016AddedAdded to the ICD-10-CM code setEffective October 1, 2015, the first year of ICD-10-CM.
FY 2017–2026No changes
FY 2027CurrentCurrent code set, no changesEffective October 1, 2026 through September 30, 2027.

Questions About S21.149AOverview

Is S21.149A a billable code?

Yes. This is a billable ICD-10-CM code, specific enough to report puncture wound with foreign body of unspecified front wall of thorax without penetration into thoracic cavity, initial encounter on HIPAA-covered claims from October 1, 2026 through September 30, 2027.

What does the 7th character A in S21.149A mean?

The final character A marks the initial encounter: use it while the patient is receiving active treatment for puncture wound with foreign body of unspecified front wall of thorax without penetration into thoracic cavity, such as an emergency visit or first evaluation.

What MS-DRG does S21.149A group to?

When puncture wound with foreign body of unspecified front wall of thorax without penetration into thoracic cavity, initial encounter is the principal diagnosis on an inpatient stay, it groups to MS-DRG 964, 965, 914, 913, 963, with relative weights from 0.9281 to 2.6361 depending on complications. Higher weights mean higher Medicare reimbursement.

Is S21.149A a CC or MCC?

CMS lists S21.149A 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 95 closely related codes in its exclusion list.

Can S21.149A be reported with S28.1?

Not as a rule. The Excludes1 note at S21, which applies to S21.149A, lists "traumatic amputation (partial) of thorax (S28.1)". An Excludes1 note means the excluded code is never reported together with this one; the only exception is when the two conditions are unrelated to each other (Official Guidelines, Section I.A.12.a).