Radiographic characteristics of wrists in idiopathic carpal tunnel syndrome patients

To determine the radiographic characteristics of wrists in idiopathic carpal tunnel syndrome patients, we compared the radiographic parameters of the wrists between carpal tunnel syndrome patients and non-symptomatic controls. We evaluated radiographic parameters of 94 wrists of 62 idiopathic carpal tunnel syndrome patients and 94 asymptomatic wrists of 94 controls. Carpal tunnel syndrome was diagnosed by clinical findings and nerve conduction studies. The lack of symptoms was confirmed with the medical records and interviews for the controls. X-ray images of the postero-anterior and lateral views of the wrist were taken. Using the obtained X-ray images, the indices of radial inclination, volar tilt, ulnar variance, and transverse and antero-posterior diameters of the wrists were measured. Two raters independently performed the measurement. One rater measured without information of clinical symptoms. Inter-rater reliabilities for each parameter were evaluated by the intra-class correlation coefficients. The averages of the measurements of two raters were compared between the carpal tunnel syndrome patients and the controls. The intra-class correlation coefficients were 0.58 for radial inclination, 0.77 for ulnar variance, 0.99 for transverse diameter, 0.60 for volar tilt, and 0.91 for antero-posterior diameter. Statistically significant correlations were found for all parameters (P