en جراحی دست / آرنج Hand surgery / Elbow پژوهشی Research Article <strong>Background</strong>: Carpal tunnel syndrome (CTS) is a common disorder with several known risk factors. However, the role of radiographic characteristics of the distal radius and risk factors of CTS has been overlooked.<br> Objectives: To identify radiographic characteristics of the distal radius as the risk factors of CTS.<br> <strong>Methods</strong>: In a case-control study, 60 patients with CTS who underwent surgical treatment (case group) and 60 people who underwent radiographic evaluation for reasons other than CTS (control group) were included. The case and control participants were matched for age and sex. Radiographic records of the patients were reviewed in the picture archiving and communication system, and the distal radius characteristics, including volar tilt, radius slope, radius height, and ulnar variance, were investigated.<br> <strong>Results</strong>: The Mean&plusmn;SD volar tilt was 10.49&plusmn;6.42&ordm; in the case group and 16.65&plusmn;5.31&ordm; in the control group (P <0.001). The Mean&plusmn;SD radius inclination angle was 19.58&plusmn;4.72&ordm; in the case group and 17.88&plusmn;4.88&ordm; in the control group (P=0.049). The Mean&plusmn;SD height of radius was 10.30&plusmn;3.21 mm in the case group and 12.24&plusmn;5.33 mm in the control group (P=0.017). The Mean&plusmn;SD ulnar variance was 1.36&plusmn;1.43 mm in the case group and 0.75&plusmn;0.27 mm in the control groups (P=0.002).<br> <strong>Conclusion</strong>: Radiological characteristics of the distal radius are significantly different between the CTS and non-CTS patients and could be regarded as the inherent risk factors of CTS development. Carpal tunnel syndrome, Distal radius, Volar tilt, Ulnar variance 207 212 http://jros.iums.ac.ir/browse.php?a_code=A-10-785-2&slc_lang=en&sid=1 Homan Shariatzadeh Shariatzadeh_h@hotmail.com 10031947532846005676 10031947532846005676 No Bone and Joint Reconstruction Research Center, Shafa Orthopedic Hospital, Iran University of Medical Sciences, Tehran, Iran. Ali Dehghan Marvast Ali_dehqa@yahoo.com 10031947532846005677 10031947532846005677 Yes Bone and Joint Reconstruction Research Center, Shafa Orthopedic Hospital, Iran University of Medical Sciences, Tehran, Iran. Mohsen Barkam Drbarkam@gmail.com 10031947532846005678 0003-0003-2904-2522 No Bone and Joint Reconstruction Research Center, Shafa Orthopedic Hospital, Iran University of Medical Sciences, Tehran, Iran.