ICD-10 Code M05.76 – Rheumatoid arthritis with rheumatoid factor of knee without organ or systems involvement (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code M05.76 – Rheumatoid arthritis with rheumatoid factor of knee without organ or systems involvement
What it is
This code identifies rheumatoid arthritis affecting the knee in a patient who has rheumatoid factor, without documented involvement of other organs or body systems. Use it when the record specifies the knee and excludes systemic complications.
Clinical signs
Typical findings include chronic inflammatory knee pain, swelling, stiffness, and reduced range of motion. Clinical features vary; refer to documentation for confirmation of rheumatoid factor and absence of extra-articular involvement.
When to use this code
Use this code when the provider documents rheumatoid arthritis with rheumatoid factor limited to the knee. It is appropriate when the note clearly states no organ or system involvement, and the knee is the named joint. Check documentation if laterality or systemic disease is unclear.
Do not use for
Do not use it for rheumatoid arthritis without rheumatoid factor, other joints only, or cases with documented organ or system involvement. Check documentation if the record does not specify the knee.
Coding tip
Confirm both the rheumatoid factor finding and the absence of systemic involvement before assigning M05.76.