M05.66 Rheumatoid arthritis of knee with involvement of other organs and systems

Non-billable header with 3 child codes.

Applies from M05 Rheumatoid arthritis with rheumatoid factor

Excludes1 (never code together)

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

Codes under M05.66

• 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
• M05.669 Rheumatoid arthritis of unspecified knee with involvement of other organs and systems

Code annotations containing back-references to M05.66

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.-)")

Diagnosis Index entries for M05.66

• Rheumatoid › arthritis › with involvement of organs NEC › knee

Nearby codes

• M05.649 Rheumatoid arthritis of unspecified hand with involvement of other organs and systems
• M05.65 Rheumatoid arthritis of hip with involvement of other organs and systems
• 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 (this code)
• 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
• 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