ICD-10-CM · FY 2026 APRIL UPDATE

S21.4

Open wound of back wall of thorax with penetration into thoracic cavity

Diagnosis reference

Nonbillable category

This entry is a category or subcategory. Choose the appropriate billable descendant based on the clinical documentation.

Effective periodOctober 1, 2026–September 30, 2027

SourceCMS ICD-10-CM order file

ClassificationDiagnosis · clinical modification

Related entries

Up to 30 descendants in this category

CODE	DESCRIPTION	TYPE
S21.40	Unspecified open wound of back wall of thorax with penetration into thoracic cavity	Category
S21.401	Unspecified open wound of right back wall of thorax with penetration into thoracic cavity	Category
S21.401A	Unspecified open wound of right back wall of thorax with penetration into thoracic cavity, initial encounter	Billable
S21.401D	Unspecified open wound of right back wall of thorax with penetration into thoracic cavity, subsequent encounter	Billable
S21.401S	Unspecified open wound of right back wall of thorax with penetration into thoracic cavity, sequela	Billable
S21.402	Unspecified open wound of left back wall of thorax with penetration into thoracic cavity	Category
S21.402A	Unspecified open wound of left back wall of thorax with penetration into thoracic cavity, initial encounter	Billable
S21.402D	Unspecified open wound of left back wall of thorax with penetration into thoracic cavity, subsequent encounter	Billable
S21.402S	Unspecified open wound of left back wall of thorax with penetration into thoracic cavity, sequela	Billable
S21.409	Unspecified open wound of unspecified back wall of thorax with penetration into thoracic cavity	Category
S21.409A	Unspecified open wound of unspecified back wall of thorax with penetration into thoracic cavity, initial encounter	Billable
S21.409D	Unspecified open wound of unspecified back wall of thorax with penetration into thoracic cavity, subsequent encounter	Billable
S21.409S	Unspecified open wound of unspecified back wall of thorax with penetration into thoracic cavity, sequela	Billable
S21.41	Laceration without foreign body of back wall of thorax with penetration into thoracic cavity	Category
S21.411	Laceration without foreign body of right back wall of thorax with penetration into thoracic cavity	Category
S21.411A	Laceration without foreign body of right back wall of thorax with penetration into thoracic cavity, initial encounter	Billable
S21.411D	Laceration without foreign body of right back wall of thorax with penetration into thoracic cavity, subsequent encounter	Billable
S21.411S	Laceration without foreign body of right back wall of thorax with penetration into thoracic cavity, sequela	Billable
S21.412	Laceration without foreign body of left back wall of thorax with penetration into thoracic cavity	Category
S21.412A	Laceration without foreign body of left back wall of thorax with penetration into thoracic cavity, initial encounter	Billable
S21.412D	Laceration without foreign body of left back wall of thorax with penetration into thoracic cavity, subsequent encounter	Billable
S21.412S	Laceration without foreign body of left back wall of thorax with penetration into thoracic cavity, sequela	Billable
S21.419	Laceration without foreign body of unspecified back wall of thorax with penetration into thoracic cavity	Category
S21.419A	Laceration without foreign body of unspecified back wall of thorax with penetration into thoracic cavity, initial encounter	Billable
S21.419D	Laceration without foreign body of unspecified back wall of thorax with penetration into thoracic cavity, subsequent encounter	Billable
S21.419S	Laceration without foreign body of unspecified back wall of thorax with penetration into thoracic cavity, sequela	Billable
S21.42	Laceration with foreign body of back wall of thorax with penetration into thoracic cavity	Category
S21.421	Laceration with foreign body of right back wall of thorax with penetration into thoracic cavity	Category
S21.421A	Laceration with foreign body of right back wall of thorax with penetration into thoracic cavity, initial encounter	Billable
S21.421D	Laceration with foreign body of right back wall of thorax with penetration into thoracic cavity, subsequent encounter	Billable

Use the complete reference

This reference does not reproduce the full tabular hierarchy, inclusion notes, Excludes1/2 notes, sequencing instructions, or seventh-character rules. Review the official tables and coding guidelines.

Open official CMS files

ICD-10-CM codes describe diagnoses. They do not have an independent Medicare PFS reimbursement amount, and billability alone does not establish coverage.