The Association of Kienböck's Disease and Uulnar Variance in the Iranian Population

This study presents the distribution of ulnar variance among Iranian patients with Kienbock’s disease and a control group of normal adults of Iranian population. We evaluated the relationship between ulnar negative variance and Kienbock’s disease in our patients. This study included two groups. In the first group، we، retrospectively، reviewed our orthopaedic department clinic charts in two hospitals in Urmia-Iran، and collected the distribution of ulnar variances in 60 patients with Kienbock’s disease. The second group comprised the distribution of ulnar variances in 400 standard wrist radiographies of normal adult population. Comparisons were made between the findings of the two groups. The mean ulnar variance of the Kienbock’s group was negative 1. 1±1. 7 and the mean ulnar variance of the general population was positive 0. 7±1. 5. The difference of the ulnar variance means was statistically significant (p<. 001). There were 38 (63%) ulnar negative، 16 (27%) neutral and 6 (10%) ulnar positive variance in the Kienbock’s group and preponderance of ulnar negative variance was statistically significant (p=. 027). There were 56 (14%) ulnar negative، 160 (40%) neutral and 184 (46%) ulnar positive variance in the control group and there was no correlation with age or sex. There was an association between ulnar negative variance and development of Kienbock’s disease in this study (p<. 001). The findings of this study support the hypothesis that there is an association between the ulnar negative variance and development of Kienbock’s disease.