Importance of measurement methods and demographic characteristics in evaluating ulnar variance: A retrospective comparative study.

OBJECTIVE

This study aimed to compare 2 methods of ulnar variance (UV) measurement (the perpendicular method and the circular method) and to determine whether UV changed based on the demographic characteristics (sex and age).

METHODS

UV was measured on bilateral wrist radiographs of 124 patients (62 men, 62 women; mean age=48.5 years; range=18-79 years) who had no history of trauma, congenital wrist anomaly, previous wrist surgery, and wrist osteoarthritis by a single radiologist with 4 years of experience. All measurements were made on standardized radiographic images using 2 methods: the perpendicular method and the circular method. All the patients were then divided into groups based on sex and age, and the study population was determined by selecting a similar number of patients for each sex and age group.

RESULTS

The mean UV of the right and left wrists was measured as 0.33 (range=-4.3 to 5.7) mm by the perpendicular method and as 0.034 (range=-5 to 5.7) mm by the circular method. A significant difference was determined between the 2 measurement methods (p<0.001). There was a statistically significant difference between sex and UV values in the left wrist measurements by both methods (p<0.05). A significant correlation was found between the UV and age in both right and left side measurements, indicating a statistically significant difference between the methods (p<0.001).

CONCLUSION

The results of our study demonstrated significant differences in the UV measurement between the 2 methods. Furthermore, UV measurement may change based on age and sex. These differences should be considered in the treatment planning of patients with wrist disorders.

LEVEL OF EVIDENCE

Level IV, Therapeutic Study.