A preliminary exploration of ulnar variance in healthy wrists at a tertiary hospital in Jeddah

Objectives: To gain preliminary insight by exploring ulnar variance changes in a Saudi-based sample. Methods: This 6-month (December 2013 to June 2014) cross-sectional study was conducted on a randomly selected healthy adult volunteers with a sample size of 104, at King Abdulaziz University Hospital, Jeddah, Saudi Arabia. Posteroanterior (PA), anteroposterior (AP), and PA grip views are taken. The variables of interest were the PA, AP, and PA fist measurements of both right and left wrists. An independent t-test was used to compare means between groups. Results: A total of 104 volunteers were recruited. Among 17 participants who had a negative ulnar variance on right PA views, a significantly high proportion (n=9; 56.2%) maintained a negative value on fist views; 7 participants (43.8%) had a neutral ulnar variance while none (0%) had a positive value (p<0.001). Similarly, a significant proportion of participants who had neutral, or positive values on right PA views maintained the same values on right fist views (p<0.001). On radiographs of the right wrist, the ulnar variance decreased with a change in wrist position, with an absolute difference in magnitude of 2.13 (p<0.001) between PA and AP views. Similarly, the ulnar variance on the left side decreased significantly between PA and AP views (absolute difference in magnitude, 1.68; p<0.001). Conclusions: Ulnar variance changes in our sample are similar to what is reported in the literature.