Rheumatoid myopathy with rheumatoid arthritis of left hip

This code signifies a muscular disorder directly caused by rheumatoid arthritis, specifically affecting the left hip joint. It indicates that the muscle pathology is a direct consequence of the inflammatory process of rheumatoid arthritis rather than a separate, unrelated myopathy.

Apply this code when documentation clearly states rheumatoid myopathy in the context of a patient diagnosed with rheumatoid arthritis, with the left hip being the affected joint. Supporting documentation should include physician notes detailing the myopathy and its direct association with the patient's rheumatoid arthritis.

• Ensure the documentation explicitly links the myopathy to rheumatoid arthritis; otherwise, a non-rheumatoid myopathy code may be more appropriate.
• Always code the underlying rheumatoid arthritis first (e.g., M05.xx or M06.xx) as the primary diagnosis, followed by this code.
• Verify laterality. This code is specific to the left hip; use M05.451 for the right hip or M05.459 for unspecified hip.