ICD-10 Code M05.419 – Rheumatoid myopathy with rheumatoid arthritis of unspecified shoulder (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code M05.419 – Rheumatoid myopathy with rheumatoid arthritis of unspecified shoulder
What it is
This code identifies rheumatoid arthritis affecting an unspecified shoulder, with associated rheumatoid myopathy. Use it when the record shows both inflammatory joint disease and muscle involvement in the same shoulder.
Clinical signs
Typical findings include shoulder pain, stiffness, reduced range of motion, and weakness related to rheumatoid inflammation. Clinical features vary; refer to documentation.
When to use this code
Use M05.419 when the provider documents rheumatoid arthritis with rheumatoid myopathy in an unspecified shoulder and does not name right or left. The note should support both the rheumatoid arthritis diagnosis and the muscle involvement. If the shoulder side is later documented, code to the more specific option.
Do not use for
Do not use it for shoulder pain or weakness without documented rheumatoid arthritis and myopathy. Do not use this code when a specific shoulder side is documented and another code is more exact.
Coding tip
Check the chart for laterality and explicit linkage between rheumatoid arthritis and myopathy before assigning this code.