Comparison of Conduction Velocity and Cross-Sectional Area of Median Nerve in Healthy Individuals with and Without Cuboid Wrist

The cuboid or square shaped wrist has been suggested in the previous studies as a predisposing factor for CTS. The aim of this study was to compare the conduction velocity and cross-sectional area of the median nerve in the wrist of healthy individuals with and without a cuboid wrist in ultrasonographic and electrodiagnostic studies.

In a analytic cross-sectional study, the volunteers at the beginning of the study, antero-posterior and medio-lateral diameters of their wrists were measured by calipers and those with a wrist-ratio greater than or equal to0.7were considered as a case group and individuals with lesser were considered as a control group. Then, the cross-sectional area of the median nerve at the entrance of the carpal tunnel was assessed by ultrasound and the conduction velocity of the nerve was assessed by electrodiagnostic tests in both groups.

In this study, 80 healthy hands were evaluated in two groups with and without cuboid wrist. The mean nerve conduction velocity in the median nerve was 47.15 m/s in individuals with a cuboid wrist and 51.93m/s in healthy individuals.The mean cross-sectional area of the median nerve in individuals with a cuboid wrist and in the control group was 10.6mm and 8.2mm, respectively.

The present study showed that the mean cross-sectional area of the median nerve in healthy individuals with a cuboid wrist is higher and the use of ultrasound in the diagnosis of CTS in these individuals may be associated with a false positive result. Therefore, it is necessary to consider the wrist-ratio and further evaluations in these people.