ICD-10 Code M05.819 – Other rheumatoid arthritis with rheumatoid factor of unspecified shoulder (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code M05.819 – Other rheumatoid arthritis with rheumatoid factor of unspecified shoulder
What it is
This code identifies rheumatoid arthritis with a positive rheumatoid factor affecting an unspecified shoulder. Use it when the record documents RA involving the shoulder but does not specify right or left.
Clinical signs
Typical findings include chronic inflammatory joint pain, stiffness, swelling, and reduced shoulder motion. Clinical features vary; refer to documentation for the affected side and any supporting rheumatology assessment.
When to use this code
Use M05.819 when the provider documents rheumatoid arthritis with rheumatoid factor and names the shoulder as the involved joint, but laterality is not stated. It is appropriate for encounter notes, problem lists, or specialist assessments that support RA of an unspecified shoulder.
If the chart later specifies right or left shoulder, code the laterality instead. Check documentation when the record only says “arthritis” or does not clearly confirm rheumatoid factor positivity.
Do not use for
Do not use this code for osteoarthritis, traumatic shoulder pain, or rheumatoid arthritis without rheumatoid factor. Also avoid it when the provider specifies a different joint or a specific shoulder side.
Coding tip
Confirm both rheumatoid factor involvement and absent laterality before assigning M05.819.