ICD-10 Code M05.851 – Other rheumatoid arthritis with rheumatoid factor of right hip (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code M05.851 – Other rheumatoid arthritis with rheumatoid factor of right hip
What it is
This code identifies rheumatoid arthritis affecting the right hip, with rheumatoid factor documented, but not a more specific rheumatoid arthritis subtype. Use it when the record clearly links the right hip involvement to seropositive rheumatoid disease.
Clinical signs
Typical findings include inflammatory joint pain, stiffness, swelling, and reduced range of motion in the hip. Clinical features vary; refer to documentation for evidence of rheumatoid factor positivity and right hip involvement.
When to use this code
Use this code when the provider documents other rheumatoid arthritis with rheumatoid factor affecting the right hip. It is appropriate when the right hip is specifically named as involved and the diagnosis is not classified elsewhere. Check documentation if laterality or seropositive status is unclear.
Do not use for
Do not use this code for rheumatoid arthritis without rheumatoid factor, or when the left hip or both hips are documented instead. Do not assign it if the note does not confirm right hip involvement.
Coding tip
Verify both the rheumatoid factor status and the right-sided joint site before assigning M05.851.