ICD-10-CM > S00-T88 > T20-T25 > T22 > T22.4 > T22.42 > T22.421 T22.421 Corrosion of unspecified degree of right elbow Non-Billable/Non-Specific Codes T22.421A..., initial encounterT22.421D..., subsequent encounterT22.421S..., sequela