ICD-10-CM > M00-M99 > M05-M14 > M06 > M06.3 > M06.37 M06.37 Rheumatoid nodule, ankle and foot Non-Billable/Non-Specific Codes M06.371Rheumatoid nodule, right ankle and footM06.372Rheumatoid nodule, left ankle and footM06.379Rheumatoid nodule, unspecified ankle and foot