ICD-10-CM > M00-M99 > M80-M85 > M85 > M85.1 > M85.17 M85.17 Skeletal fluorosis, ankle and foot Non-Billable/Non-Specific Codes M85.171Skeletal fluorosis, right ankle and footM85.172Skeletal fluorosis, left ankle and footM85.179Skeletal fluorosis, unspecified ankle and foot