Fig. 1.

The carpal tunnel. Scanning technique for the assessment of proximal and distal end of the carpal tunnel. The Guyon’s Canal is assessed using a similar transducer position as in the carpal tunnel (perpendicular to the long axis of the limb), however, the transducer should be slightly shifted to the ulnar side. Ultrasound images obtained at the indicated transducer positions are shown in Fig. 2