ICD-10-CM > S00-T88 > S20-S29 > S20 > S20.4 > S20.41 S20.41 Abrasion of back wall of thorax Non-Billable/Non-Specific Codes S20.411Abrasion of right back wall of thoraxS20.411A..., initial encounterS20.411D..., subsequent encounterS20.411S..., sequelaS20.412Abrasion of left back wall of thoraxS20.412A..., initial encounterS20.412D..., subsequent encounterS20.412S..., sequelaS20.419Abrasion of unspecified back wall of thoraxS20.419A..., initial encounterS20.419D..., subsequent encounterS20.419S..., sequela