ICD-10-CM > S00-T88 > T20-T25 > T25 > T25.4 > T25.49 > T25.492 T25.492 Corrosion of unspecified degree of multiple sites of left ankle and foot Non-Billable/Non-Specific Codes T25.492A..., initial encounterT25.492D..., subsequent encounterT25.492S..., sequela