Park J H, Jang W Y, Kwak D H, Park J W
Korea University College of Medicine, 73, Inchon-ro, Sungbuk-gu, Seoul 06334, South Korea.
Bone Joint J. 2017 Nov;99-B(11):1508-1514. doi: 10.1302/0301-620X.99B11.BJJ-2016-1238.R2.
Positive ulnar variance is an established risk factor for idiopathic ulnar impaction syndrome (UIS). However, not all patients with positive ulnar variance develop symptomatic UIS and other factors, including the morphology of the lunate, may be involved. The aim of this study was to clarify the relationship between lunate morphology and idiopathic UIS.
A cohort of 95 patients with idiopathic UIS (UIS group) was compared with 95 asymptomatic controls with positive ulnar variance. The shape of the lunate was measured using the capitate-triquetrum distance (CTD), ulnar coverage ratio (UCR), radiolunate distance and radiolunate angle. The association of radiographic parameters and lunate types with the development of UIS was investigated in univariable and multivariable analyses. Receiver operating characteristic curves were used to estimate a cutoff for any statistically significant variables.
The proportion of type II lunates, which have a medial hamate facet, were significantly higher in the UIS group than in the control group in the univariable analysis (p = 0.001). CTD (odds ratio (OR) 1.52; 95% confidence interval (CI) 1.11 to 2.06; p = 0.008) and UCR (OR 44.78; 95% CI 5.35 to 374.90; p = 0.002) showed a positive association with UIS in the multivariable analysis. Estimated cutoff values were 2.5 mm for the CTD (area under the curve (AUC) = 0.65) and 0.4 for the UCR (AUC = 0.64).
The proportion of type II lunates was greater in the UIS group than in the control group. A large UCR, which represents the broad base of the lunate, was positively associated with the development of idiopathic UIS. Cite this article: 2017;99-B:1508-14.
正尺骨变异是特发性尺骨撞击综合征（UIS）的既定危险因素。然而，并非所有正尺骨变异的患者都会出现有症状的UIS，其他因素，包括月骨形态，可能也与之相关。本研究的目的是阐明月骨形态与特发性UIS之间的关系。
将95例特发性UIS患者（UIS组）与95例正尺骨变异的无症状对照者进行比较。使用头状骨-三角骨距离（CTD）、尺骨覆盖比（UCR）、桡月距离和桡月角来测量月骨的形状。在单变量和多变量分析中研究影像学参数和月骨类型与UIS发生的相关性。采用受试者工作特征曲线来估计任何具有统计学意义的变量的临界值。
在单变量分析中，具有内侧钩骨小面的II型月骨的比例在UIS组中显著高于对照组（p = 0.001）。在多变量分析中，CTD（比值比（OR）1.52；95%置信区间（CI）1.11至2.06；p = 0.008）和UCR（OR 44.78；95% CI 5.35至374.90；p = 0.002）与UIS呈正相关。CTD的估计临界值为2.5 mm（曲线下面积（AUC）= 0.65），UCR的估计临界值为0.4（AUC = 0.64）。
UIS组中II型月骨的比例高于对照组。代表月骨宽基底的较大UCR与特发性UIS的发生呈正相关。引用本文：2017；99-B：1508-14。
