ICD-10-CM > S00-T88 > S20-S29 > S23 > S23.1 > S23.11 S23.11 Subluxation and dislocation of T1/T2 thoracic vertebra Non-Billable/Non-Specific Codes S23.110Subluxation of T1/T2 thoracic vertebraS23.110A..., initial encounterS23.110D..., subsequent encounterS23.110S..., sequelaS23.111Dislocation of T1/T2 thoracic vertebraS23.111A..., initial encounterS23.111D..., subsequent encounterS23.111S..., sequela