ICD-10-CM > S00-T88 > S20-S29 > S23 > S23.1 > S23.10 > S23.100 S23.100 Subluxation of unspecified thoracic vertebra Non-Billable/Non-Specific Codes S23.100A..., initial encounterS23.100D..., subsequent encounterS23.100S..., sequela