ICD-10-CM > S00-T88 > S20-S29 > S21 > S21.2 > S21.20 > S21.202 S21.202 Unspecified open wound of left back wall of thorax without penetration into thoracic cavity Non-Billable/Non-Specific Codes S21.202A..., initial encounterS21.202D..., subsequent encounterS21.202S..., sequela