ICD-10-CM > S00-T88 > S20-S29 > S21 > S21.4 > S21.43 > S21.431 S21.431 Puncture wound without foreign body of right back wall of thorax with penetration into thoracic cavity Non-Billable/Non-Specific Codes S21.431A..., initial encounterS21.431D..., subsequent encounterS21.431S..., sequela