S21.409

Billable code

Unspecified open wound of unspecified back wall of thorax with penetration into thoracic cavity

The ICD-10 code for unspecified open wound of unspecified back wall of thorax with penetration into thoracic cavity is S21.409.

Documentation support

General coding-documentation guidance — not a substitute for payer-specific requirements or professional coding judgment.

•Laterality-specific codes exist for this condition — confirm the affected side is documented.
•As a general rule, code to the highest level of specificity supported by the documentation in the medical record.