Kawanishi Y, Moritomo H, Omori S, Kataoka T, Murase T, Sugamoto K
Department of Orthopedic Surgery, Osaka University Graduate School of Medicine, Suita, Japan.
Department of Physical Therapy, Osaka Yukioka College of Health Science, Osaka, Japan
J Hand Surg Eur Vol. 2014 Jun;39(5):526-32. doi: 10.1177/1753193413516238. Epub 2013 Dec 9.
Positive ulnar variance is associated with ulnar impaction syndrome and ulnar variance is reported to increase with pronation. However, radiographic measurement can be affected markedly by the incident angle of the X-ray beam. We performed three-dimensional (3-D) computed tomography measurements of ulnar variance and ulnolunate distance during forearm rotation and compared these with plain radiographic measurements in 15 healthy wrists. From supination to pronation, ulnar variance increased in all cases on the radiographs; mean ulnar variance increased significantly and mean ulnolunate distance decreased significantly. However on 3-D imaging, ulna variance decreased in 12 cases on moving into pronation and increased in three cases; neither the mean ulnar variance nor mean ulnolunate distance changed significantly. Our results suggest that the forearm position in which ulnar variance increased varies among individuals. This may explain why some patients with ulnar impaction syndrome complain of wrist pain exacerbated by forearm supination. It also suggests that standard radiographic assessments of ulnar variance are unreliable.
尺骨正向变异与尺骨撞击综合征相关，且据报道尺骨变异会随着旋前动作而增加。然而，X线片测量会受到X线束入射角的显著影响。我们对15例健康腕关节进行了前臂旋转过程中尺骨变异和尺月骨间距的三维（3-D）计算机断层扫描测量，并将其与普通X线片测量结果进行比较。在X线片上，从旋后到旋前，所有病例的尺骨变异均增加；平均尺骨变异显著增加，平均尺月骨间距显著减小。然而，在三维成像中，12例在旋前时尺骨变异减小，3例增加；平均尺骨变异和平均尺月骨间距均无显著变化。我们的结果表明，尺骨变异增加时的前臂位置因人而异。这可能解释了为什么一些尺骨撞击综合征患者抱怨前臂旋后会加剧腕部疼痛。这也表明尺骨变异的标准X线片评估不可靠。
