ICD-10 Code M05.451 – Rheumatoid myopathy with rheumatoid arthritis of right hip (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code M05.451 – Rheumatoid myopathy with rheumatoid arthritis of right hip
What it is
This code identifies rheumatoid arthritis affecting the right hip together with rheumatoid myopathy, meaning muscle involvement linked to the rheumatoid disease. Use it when documentation clearly ties both conditions to the same side.
Clinical signs
Typical findings include inflammatory joint pain, stiffness, and reduced hip function, along with muscle weakness or wasting attributed to rheumatoid disease. Clinical features vary; refer to documentation.
When to use this code
Use M05.451 when the record states rheumatoid arthritis of the right hip and rheumatoid myopathy are both present. It is appropriate when the provider links the myopathy to the rheumatoid condition, not to another cause. Check documentation if laterality or the muscle diagnosis is unclear.
Do not use for
Do not use this code for rheumatoid arthritis without myopathy, or for myopathy unrelated to rheumatoid disease. Do not assign it if the hip side is not documented or if another joint is specified.
Coding tip
Confirm both the rheumatoid myopathy and the right-hip laterality in the note before coding.