S21
Non-billableOpen wound of thorax
Open wound of thorax
This is a header/category code. For billing purposes, use a more specific child code from the list below.
Coding Notes
Includes
Conditions included under this code
- injuries of breast
- injuries of chest (wall)
- injuries of interscapular area
Excludes 1
Codes that cannot be used together with this code (mutual exclusion)
Excludes 2
Conditions not included here, but the patient may have both
- •burns and corrosionsT20-T32
- •effects of foreign body in bronchusT17.5
- •effects of foreign body in esophagusT18.1
- •effects of foreign body in lungT17.8
- •effects of foreign body in tracheaT17.4
- •frostbiteT33-T34
- injuries of axilla
- injuries of clavicle
- injuries of scapular region
- injuries of shoulder
- •insect bite or sting, venomousT63.4
Use Additional Code
Additional codes that should follow this code
Code Also
A second code may be required; sequencing depends on circumstances
7th Character Definitions
- A - initial encounter
- D - subsequent encounter
- S - sequela
Child Codes (6)
S21.0Open wound of breast
S21.1Open wound of front wall of thorax w/o penet thoracic cavity
S21.2Open wound of back wall of thorax w/o penet thoracic cavity
S21.3Open wound of front wall of thorax w penet thoracic cavity
S21.4Open wound of back wall of thorax w penet thoracic cavity
S21.9Open wound of unspecified part of thorax
ICD-11 Equivalents(1)
ICD-11 Equivalents
View full mappingCorresponding ICD-11 codes from the WHO crosswalk mapping
Also Known As / Clinical Terms(3)
Frequently Asked Questions
What is the ICD-10 code for open wound of thorax?
The ICD-10-CM code for open wound of thorax is S21. The full clinical description is "Open wound of thorax". S21 is a non-billable header code. Use a more specific child code for billing purposes.
What does ICD-10 code S21 mean?
ICD-10-CM code S21 represents “Open wound of thorax”. It is classified under Chapter 19: Injury, Poisoning and Certain Other Consequences of External Causes and is a non-billable header code. Use a more specific child code for billing purposes.
Is S21 a billable code?
No, S21 is a non-billable header code. You need to use one of its more specific child codes for billing. There are 6 child codes under S21.
What chapter is S21 in?
S21 is in Chapter 19: Injury, Poisoning and Certain Other Consequences of External Causes (codes S00-T88).
What codes cannot be used with S21?
S21 has Excludes1 notes indicating codes that cannot be used together with it, including: birth trauma (P10-P15); obstetric trauma (O70-O71); traumatic amputation (partial) of thorax (S28.1).
What are the subcategories under S21?
S21 has 6 child codes, including: S21.0 (Open wound of breast), S21.1 (Open wound of front wall of thorax w/o penet thoracic cavity), S21.2 (Open wound of back wall of thorax w/o penet thoracic cavity), S21.3 (Open wound of front wall of thorax w penet thoracic cavity), and 2 more.
Are additional codes required with S21?
Yes, when using S21, also report: any retained foreign body, if applicable (Z18.-).
What are the UMLS CUIs for S21?
S21 is linked to 1 UMLS Concept Unique Identifier: C0478235. The UMLS (Unified Medical Language System) integrates multiple biomedical vocabularies maintained by the U.S. National Library of Medicine.
How does S21 relate to ICF functioning codes?
ICF (International Classification of Functioning, Disability and Health) codes describe how conditions like open wound of thorax affect a person's functioning — body functions, activities, participation, and environmental factors. AutoICD provides ICF Core Sets for 12+ conditions and can map clinical text to ICF categories automatically. Browse the ICF directory to explore functioning codes.
What is the ICD-11 equivalent of S21?
S21 maps to the ICD-11 code: NA81.Z (Open wound of thorax, unspecified).
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Includes SNOMED Clinical Terms® (SNOMED CT®) used by permission of SNOMED International. Includes content from the UMLS Metathesaurus, courtesy of the U.S. National Library of Medicine.