M05.662 Rheumatoid arthritis of left knee with involvement of other organs and systems

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.-)

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)

• 714.2 Other rheumatoid arthritis with visceral or systemic involvement (approximate)

Code annotations containing back-references to M05.662

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

• M05.651 Rheumatoid arthritis of right hip with involvement of other organs and systems
• M05.652 Rheumatoid arthritis of left hip with involvement of other organs and systems
• M05.659 Rheumatoid arthritis of unspecified hip with involvement of other organs and systems
• M05.66 Rheumatoid arthritis of knee with involvement of other organs and systems
• M05.661 Rheumatoid arthritis of right knee with involvement of other organs and systems
• M05.662 Rheumatoid arthritis of left knee with involvement of other organs and systems (this code)
• M05.669 Rheumatoid arthritis of unspecified knee with involvement of other organs and systems
• M05.67 Rheumatoid arthritis of ankle and foot with involvement of other organs and systems
• M05.671 Rheumatoid arthritis of right ankle and foot with involvement of other organs and systems
• M05.672 Rheumatoid arthritis of left ankle and foot with involvement of other organs and systems
• M05.679 Rheumatoid arthritis of unspecified ankle and foot with involvement of other organs and systems