Clutton's joints

Clutton's joints refer to a specific, usually bilateral, painless, non-inflammatory synovitis of the knee joints, often associated with congenital syphilis. This condition typically presents as symmetrical swelling of the knees without significant pain, redness, or warmth. It is a late manifestation of congenital syphilis, usually appearing in late childhood or adolescence.

This code is used when documentation explicitly states "Clutton's joints" as the diagnosis, particularly in a patient with a known history of congenital syphilis or strong clinical suspicion thereof. It applies to cases presenting with characteristic bilateral knee effusions without inflammatory signs. Documentation should confirm the presence of synovitis in the knee(s) and ideally link it to congenital syphilis.

• Ensure documentation specifies "Clutton's joints" and not just general knee synovitis, as this is a very specific manifestation.
• Always code an underlying diagnosis of congenital syphilis (A50.-) as the primary diagnosis, with Clutton's joints (A50.51) as a secondary diagnosis, unless the Clutton's joints are the primary reason for the encounter.
• Do not confuse with other forms of knee arthritis or synovitis; Clutton's joints are distinct due to their association with congenital syphilis and typically non-inflammatory nature.