ICD-10 Code A50.51 – Clutton’s joints (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code A50.51 – Clutton’s joints
What it is
Clutton’s joints refers to painless swelling of the knees linked to congenital syphilis. It is a late manifestation of infection and should be coded when the condition is specifically documented.
Clinical signs
Typical findings include bilateral knee swelling with little or no pain and limited inflammation. Clinical features vary; refer to documentation, especially when the record links the joint changes to congenital syphilis.
When to use this code
Use this code when the provider documents Clutton’s joints or clearly identifies the knee swelling as a manifestation of congenital syphilis. It may also apply when the diagnosis is recorded as a classic late syphilitic joint finding. Check documentation if the note only mentions arthritis or effusion without the specific term.
Do not use for
Do not use this code for nonspecific knee pain, trauma, or inflammatory arthritis without evidence of congenital syphilis. Do not assign it when the chart does not support Clutton’s joints.
Coding tip
Code A50.51 only when the record ties the joint finding to congenital syphilis; otherwise, query or code the documented condition.