ICD-10 Code M05.431 – Rheumatoid myopathy with rheumatoid arthritis of right wrist (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code M05.431 – Rheumatoid myopathy with rheumatoid arthritis of right wrist
What it is
This code identifies rheumatoid arthritis affecting the right wrist, with associated rheumatoid myopathy. It signals inflammatory joint disease plus muscle involvement documented in the same limb.
Clinical signs
Typical findings include chronic inflammatory wrist pain, swelling, stiffness, and reduced motion, along with muscle weakness or myopathic changes. Clinical features vary; refer to documentation.
When to use this code
Use this code when the provider documents rheumatoid arthritis of the right wrist and rheumatoid myopathy together. It is appropriate when the right wrist is specifically identified and the muscle involvement is part of the diagnosis.
Check documentation if laterality is unclear or if myopathy is not explicitly linked to the rheumatoid condition. Code the documented site and condition exactly as stated.
Do not use for
Do not use it for rheumatoid arthritis without myopathy, or for myopathy unrelated to rheumatoid disease. Do not assume the right wrist if the record does not specify laterality.
Coding tip
Verify that both the rheumatoid arthritis and myopathy are documented, and confirm right-sided wrist involvement before assigning M05.431.