ICD-10-CM > S00-T88 > T20-T25 > T25 > T25.3 > T25.39 > T25.399 T25.399 Burn of third degree of multiple sites of unspecified ankle and foot Non-Billable/Non-Specific Codes T25.399A..., initial encounterT25.399D..., subsequent encounterT25.399S..., sequela