ICD-10-CM > S00-T88 > T20-T25 > T23 > T23.2 > T23.21 > T23.212 T23.212 Burn of second degree of left thumb (nail) Non-Billable/Non-Specific Codes T23.212A..., initial encounterT23.212D..., subsequent encounterT23.212S..., sequela