ICD-10 Code M05.56 – Rheumatoid polyneuropathy with rheumatoid arthritis of knee (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code M05.56 – Rheumatoid polyneuropathy with rheumatoid arthritis of knee
What it is
This code identifies rheumatoid arthritis of the knee with associated polyneuropathy. Use it when documentation shows both the inflammatory joint disease and nerve involvement linked to rheumatoid disease.
Clinical signs
Typical findings include knee pain, swelling, stiffness, and reduced range of motion, along with neuropathic symptoms such as numbness, tingling, or weakness. Clinical features vary; refer to documentation.
When to use this code
Use this code when the provider documents rheumatoid arthritis affecting the knee and specifically links polyneuropathy to the rheumatoid condition. It may also apply when the record clearly states rheumatoid neuropathy with knee involvement. Check documentation if the anatomic site or neuropathy relationship is unclear.
Do not use for
Do not use this code for rheumatoid arthritis of the knee without neuropathy, or for neuropathy from another cause. If the note does not specify the knee or does not connect the neuropathy to rheumatoid disease, check documentation.
Coding tip
Code only when both the rheumatoid knee diagnosis and the polyneuropathy are documented together and clearly linked.