ICD-10-CM > S00-T88 > T20-T25 > T21 > T21.3 T21.3 Burn of third degree of trunk Non-Billable/Non-Specific Use Additional external cause code to identify the source, place and intent of the burn (X00-X19, X75-X77, X96-X98, Y92) Codes T21.30Burn of third degree of trunk, unspecified siteT21.30XA..., initial encounterT21.30XD..., subsequent encounterT21.30XS..., sequelaT21.31Burn of third degree of chest wallT21.31XA..., initial encounterT21.31XD..., subsequent encounterT21.31XS..., sequelaT21.32Burn of third degree of abdominal wallT21.32XA..., initial encounterT21.32XD..., subsequent encounterT21.32XS..., sequelaT21.33Burn of third degree of upper backT21.33XA..., initial encounterT21.33XD..., subsequent encounterT21.33XS..., sequelaT21.34Burn of third degree of lower backT21.34XA..., initial encounterT21.34XD..., subsequent encounterT21.34XS..., sequelaT21.35Burn of third degree of buttockT21.35XA..., initial encounterT21.35XD..., subsequent encounterT21.35XS..., sequelaT21.36Burn of third degree of male genital regionT21.36XA..., initial encounterT21.36XD..., subsequent encounterT21.36XS..., sequelaT21.37Burn of third degree of female genital regionT21.37XA..., initial encounterT21.37XD..., subsequent encounterT21.37XS..., sequelaT21.39Burn of third degree of other site of trunkT21.39XA..., initial encounterT21.39XD..., subsequent encounterT21.39XS..., sequela