Fig. 2From: The correlation between pre-operative ultrasonographic median nerve evaluation and the operative procedure in CTSa Illustration drawing for median nerve flattening ratio calculation. b Ultrasonographic median nerve flattening ratio calculation at the level of hamate (flattening ratio = Distance A/Distance B) = (4.4/1.8) = 2.4. TZ, trapezium; TD, trapezoid; C, capitate; H, hamateBack to article page