ICD-10-CM 2027 diagnosis code
S21.3Open wound of front wall of thorax with penetration into thoracic cavity
S21.3 is a header code, so it can't be reported by itself. Choose one of the 6 more specific codes beneath it and add the required 7th character.Short description: Open wound of front wall of thorax w penet thoracic cavity
Code unchanged since ICD-10-CM took effect on October 1, 2015. Source: official FY2027 ICD-10-CM release from CDC/NCHS and CMS. Page updated September 29, 2026. About our data
About S21.3
S21.3 is the ICD-10-CM diagnosis code for open wound of front wall of thorax with penetration into thoracic cavity. It belongs to category S21 (open wound of thorax), block S20-S29 (injuries to the thorax) and chapter 19 (injury, poisoning and certain other consequences of external causes). It is a header code, so it can't be reported by itself; one of its 6 subcodes must be used instead.
Within S21 (open wound of thorax), S21.3 is specifically for open wound of front wall of thorax with penetration into thoracic cavity. Related codes cover breast (S21.0), front wall of thorax without penetration into thoracic cavity (S21.1), back wall of thorax without penetration into thoracic cavity (S21.2), back wall of thorax with penetration into thoracic cavity (S21.4) and unspecified part of thorax (S21.9).
Codes in this range require a 7th character: A for initial encounter, D for subsequent encounter and S for sequela. Use placeholder "X" characters to fill any empty positions before the 7th character.
It has been part of ICD-10-CM since the code set took effect on October 1, 2015 and hasn't changed since.
7th character
The appropriate 7th character is to be added to each code from category S21
- S21.30Unspecified open wound of front wall of thorax with penetration into thoracic cavity
- S21.31Laceration without foreign body of front wall of thorax with penetration into thoracic cavity
- S21.311Laceration without foreign body of right front wall of thorax with penetration into thoracic cavity
- S21.312Laceration without foreign body of left front wall of thorax with penetration into thoracic cavity
- S21.319Laceration without foreign body of unspecified front wall of thorax with penetration into thoracic cavity
- S21.32Laceration with foreign body of front wall of thorax with penetration into thoracic cavity
- S21.321Laceration with foreign body of right front wall of thorax with penetration into thoracic cavity
- S21.322Laceration with foreign body of left front wall of thorax with penetration into thoracic cavity
- S21.329Laceration with foreign body of unspecified front wall of thorax with penetration into thoracic cavity
- S21.33Puncture wound without foreign body of front wall of thorax with penetration into thoracic cavity
- S21.331Puncture wound without foreign body of right front wall of thorax with penetration into thoracic cavity
- S21.332Puncture wound without foreign body of left front wall of thorax with penetration into thoracic cavity
- S21.339Puncture wound without foreign body of unspecified front wall of thorax with penetration into thoracic cavity
- S21.34Puncture wound with foreign body of front wall of thorax with penetration into thoracic cavity
- S21.341Puncture wound with foreign body of right front wall of thorax with penetration into thoracic cavity
- S21.342Puncture wound with foreign body of left front wall of thorax with penetration into thoracic cavity
- S21.349Puncture wound with foreign body of unspecified front wall of thorax with penetration into thoracic cavity
- S21.35Open bite of front wall of thorax with penetration into thoracic cavity
- Ainitial encounter
- Dsubsequent encounter
- Ssequela
Coding notes
- Open wound of chest with penetration into thoracic cavity
Notes that apply from higher levels
Instructions written at a parent level also apply to S21.3.
› From S21 Open wound of thorax
- traumatic amputation (partial) of thorax (S28.1)
Broader instructions also apply from S20-S29 Injuries to the thorax and Chapter 19: Injury, poisoning and certain other consequences of external causes.
Code history
- 2016
- 2017
- 2018
- 2019
- 2020
- 2021
- 2022
- 2023
- 2024
- 2025
- 2026
- 2027
- FY2016 (effective 10/1/2015): Added (first year of ICD-10-CM)
- No changes since FY2016.
Common questions about S21.3
Is S21.3 billable?
- No. S21.3 is a header code. Report one of its more specific subcodes instead.