M05.061 Felty's syndrome, right knee

Billable ICD-10-CM code, FY2026.

Applies from M05 Rheumatoid arthritis with rheumatoid factor

Excludes1 (never code together)

• rheumatic fever (I00)
• juvenile rheumatoid arthritis (M08.-)
• rheumatoid arthritis of spine (M45.-)

Applies from M05.0 Felty's syndrome

Applicable to

• Rheumatoid arthritis with splenoadenomegaly and leukopenia

Risk adjustment (HCC)

• CMS-HCC V28: HCC 93 — Rheumatoid Arthritis and Other Specified Inflammatory Rheumatic Disorders
• CMS-HCC V22: HCC 40 — Rheumatoid Arthritis and Inflammatory Connective Tissue Disease
• RxHCC V08: HCC 83 — Rheumatoid Arthritis and Other Inflammatory Polyarthropathy
• ESRD V24: HCC 40

MS-DRG index

Defines the logic of DRG(s) 545-547 in MDC 08.

Approximate ICD-9-CM (GEMs)

• 714.1 Felty's syndrome (approximate)

Code annotations containing back-references to M05.061

Back-references to M05.0

• Type 1 Excludes: M08 Juvenile arthritis ("Felty's syndrome (M05.0)")

Back-references to M05

• Code Also: I27.21 Secondary pulmonary arterial hypertension ("rheumatoid arthritis (M05.-)")
• Type 1 Excludes: R76.81 Abnormal rheumatoid factor and anti-citrullinated protein antibody without rheumatoid arthritis ("rheumatoid arthritis with rheumatoid factor (M05.-)")

Nearby codes

• M05.05 Felty's syndrome, hip
• M05.051 Felty's syndrome, right hip
• M05.052 Felty's syndrome, left hip
• M05.059 Felty's syndrome, unspecified hip
• M05.06 Felty's syndrome, knee
• M05.061 Felty's syndrome, right knee (this code)
• M05.062 Felty's syndrome, left knee
• M05.069 Felty's syndrome, unspecified knee
• M05.07 Felty's syndrome, ankle and foot
• M05.071 Felty's syndrome, right ankle and foot
• M05.072 Felty's syndrome, left ankle and foot