ICD-10 Code M05.429 – Rheumatoid myopathy with rheumatoid arthritis of unspecified elbow (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code M05.429 – Rheumatoid myopathy with rheumatoid arthritis of unspecified elbow
What it is
This code identifies rheumatoid arthritis affecting an unspecified elbow, with associated rheumatoid myopathy. Use it when the record links elbow rheumatoid arthritis and muscle involvement, but does not specify right or left side.
Clinical signs
Findings may include chronic inflammatory joint pain, swelling, stiffness, and reduced elbow motion, along with muscle weakness or myopathic changes attributed to rheumatoid disease. Clinical features vary; refer to documentation.
When to use this code
Use this code when the provider documents rheumatoid myopathy and rheumatoid arthritis in the elbow, and laterality is not stated. It is appropriate when the elbow is clearly involved but the chart does not identify right or left. Check documentation if the muscle disorder is not explicitly linked to rheumatoid arthritis.
Do not use for
Do not use this code for rheumatoid arthritis of the elbow without documented myopathy, or for myopathy unrelated to rheumatoid disease. Do not assign it when the record specifies a different joint or a definite right or left elbow code.
Coding tip
Confirm both the rheumatoid arthritis and myopathy are documented together before assigning M05.429.