[An anatomical study of the carpal tunnel for endoscopic carpal tunnel release].

An anatomical study of the carpal tunnel was performed to characterize the transverse carpal ligament, enabling improved endoscopic carpal tunnel release. One hundred wrist joints obtained from 50 cadavers were studied. The width of the transverse carpal ligament (TCL) was found to be narrower in females than in males, and there was no significant difference in the width of the ligament between the right and the left wrist joints. The length of the TCL was not significantly different between males and females or between the right and left wrist joints. On the sagittal plane, the TCL was spindle-shaped and its thickest part was in the distal third. The thickness of the TCL had a significant negative correlation with age. The width of the TCL had a significant positive correlation with both its length (p < 0.01) and the thickness of its distal part (p < 0.01). Neither the distance between the distal edge of the TCL and the superficial palmar arch nor the distance between the radial edge of the pisiform bone and the ulnar artery at the distal edge of the TCL were significantly correlated with sex, laterality, or age. These results indicated that the width and thickness of the TCL and the ulnar artery can be predicted by calculating the length of the TCL percutaneously, thus enabling a safe and reliable endoscopic carpal tunnel release to be performed clinically without any complication.