ICD-10 Code M05.64 – Rheumatoid arthritis of hand with involvement of other organs and systems (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code M05.64 – Rheumatoid arthritis of hand with involvement of other organs and systems
What it is
This code identifies rheumatoid arthritis affecting the hand, with documented involvement of other organs or body systems. Use it when the record links the hand arthritis to systemic rheumatoid disease.
Clinical signs
Typical findings include inflammatory hand joint pain, swelling, stiffness, and reduced function. Clinical features vary; refer to documentation for evidence of extra-articular or systemic involvement.
When to use this code
Use this code when the provider documents rheumatoid arthritis in the hand and specifies involvement of other organs or systems. It fits cases where the hand is the named site and the disease is not limited to joints alone.
Check the note for laterality, if reported, and for any additional rheumatoid arthritis manifestations. If the record does not clearly support systemic involvement, you should not assume it.
Do not use for
Do not use this code for rheumatoid arthritis without hand involvement, or for unspecified inflammatory arthritis. Do not assign it when systemic involvement is not documented; check documentation.
Coding tip
Code only what the provider explicitly links: hand involvement plus other organ or system involvement.