ICD-10-CM > M00-M99 > M05-M14 > M05 > M05.8 > M05.87 M05.87 Other rheumatoid arthritis with rheumatoid factor of ankle and foot Non-Billable/Non-Specific Codes M05.871Other rheumatoid arthritis with rheumatoid factor of right ankle and footM05.872Other rheumatoid arthritis with rheumatoid factor of left ankle and footM05.879Other rheumatoid arthritis with rheumatoid factor of unspecified ankle and foot