The effect of ulnar variance on scapholunate and capitolunate angles

Abstract

Background Ulnar variance (UV), which is measured using anteroposterior (AP) X-rays, is associated with the development of multiple wrist pathologies. The scapholunate angle (SLA) and capitolunate angle (CLA) are measured using lateral X-rays, and these can be used in the diagnosis of intercalated segmental instability. Purpose To determine the effect of UV on SLA and CLA. Material and Methods A total of 140 patients (73 women, 67 men; mean age, 37.8 ± 14.6 years; 95% confidence interval [CI], 35.4–40.3) were included in the study. Participants were excluded if they presented with fractures or malunions, any arthritic conditions, avascular necrosis, congenital deformities, or bone and soft tissue tumors. UV, SLA, and CLA were measured using AP and lateral wrist X-rays. Results Patients were grouped as positive, neutral, and negative UV. There was no statistically significant difference in mean ages, sex, and sides (left or right) between the UV groups ( P > 0.05). In addition, there was no statistically significant difference in the mean values of SLA and CLA between the UV groups ( P > 0.05). UV showed no statistically significant association with SLA and CLA (r = –0.064; P = 0.455, and r = 0.059; P = 0.485, respectively). However, there was a statistically significant association between SLA and CLA (r = –0.482; P < 0.001). Conclusion There is higher prevalence of neutral UV and no correlation between UV with respect to age and sex of patients in the local Turkish population. SLA and CLA are not affected by UV. There is a negative correlation between SLA and CLA.