The most reliable probe position in the ultrasonographic examination of the wrist in rheumatoid arthritis.

Objectives: This study aims to evaluate the inter-observer reliability of the ultrasonographic examination of the wrist in RA patients between 3 examiners and 3 probe positions.

Methods: Fifty-three RA patients were recruited at the University Clinical Hospital of Santiago de Compostela in Spain for ultrasonographic examination of the wrist. Ultrasonography (US) was performed on both wrists using a GE LOGIQ 9 machine, using three probe positions: Lister's Tubercle to digit II (position 1), Lister's Tubercle to digit III (position 2) and ulnocarpal (position 3), from the anatomic medial orientation.