Ultradistal Level in Carpal Tunnel Syndrome Diagnosis

This original research article investigates the effectiveness of using ultrasound to diagnose carpal tunnel syndrome (CTS) by incorporating the ultradistal level of the median nerve (MN). The study includes a case-control design with 219 patients diagnosed with primary CTS and 39 healthy controls. The research aims to assess whether measuring the cross-sectional area (CSA) of the MN at the ultradistal level enhances diagnostic accuracy compared to traditional measurements at proximal and distal levels. The CSA was significantly higher in patients than in controls, particularly at the ultradistal level. The study establishes specific CSA cut-off values for each wrist level and evaluates various definitions for ultrasound-based CTS diagnosis. The findings suggest that including the ultradistal level improves the sensitivity and specificity of ultrasound in diagnosing CTS, advocating for its integration into clinical practice. The article contributes to the understanding of CTS diagnosis and proposes a refined ultrasound protocol for clinical use.