Background

The watershed line is widely accepted as the distal limit of the volar locking plate (VLP); however, the VLP placement could vary depending on the plate contour and morphology of the distal radius. The aim of this study was to investigate the morphology of the distal radius and VLP fitting using 3D images.

Hypothesis

We hypothesized that attachment of the VLP would affect the contour of the volar prominence of the distal radius.

Patients and methods

Variable-angle LCP two-column volar distal radius Plate 2.4 and 16 formalin-fixed cadavers were studied. The plate and forearm were scanned using a computed tomography scanner. The plate was fixed to the radial shaft in the most distal position without flexor pollicis longus tendon contact. Postero-antero and lateral radiographs were obtained using fluoroscopy. Postero-antero radiographs were superimposed on a 3D image of the distal radius. The virtual plate was attached to the distal radius in the computer simulations and the plate was adjusted in the sagittal plane. In the postero-antero radiographs, the distance between the plate and distal end of the radius (DPR) was measured. In the sagittal plane, the height of the volar lunate facet (VLF) and the plate-to-bone distance of each locking screw hole was measured. The volar cortical angle (VCA) was measured as the angle formed by a line drawn along the volar surface and a line drawn on the radial shaft on the sagittal plane at each locking screw plane.

Results

A significant correlation was observed between the height of the VLF and the DPR and between the height of the VLF and the VCA. The plate-to-bone distance at the ulnar screw hole was significantly smaller than that of the other screw holes.

Discussion

Our study revealed that the higher the VLF, the more proximal is the VLP. The plate fits on the bone surface at the ulnar side, whereas the radial side has more space between the plate and bone.

Level of Evidence

III, diagnostic Level.

中文翻译：

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参考掌侧锁定钢板手术的桡骨远端三维成像

背景

分水岭线被广泛接受为掌侧锁定板 (VLP) 的远端界限；然而，VLP 的放置可能会因钢板轮廓和桡骨远端的形态而异。本研究的目的是使用 3D 图像研究桡骨远端的形态和 VLP 拟合。

假设

我们假设 VLP 的附着会影响桡骨远端掌侧突起的轮廓。

患者和方法

研究了可变角度 LCP 双柱掌侧桡骨远端板 2.4 和 16 具福尔马林固定的尸体。使用计算机断层扫描仪扫描板和前臂。钢板固定在桡骨干的最远端位置，没有拇长屈肌腱接触。使用荧光透视法获得后前位和侧位 X 线片。前后位射线照片叠加在桡骨远端的 3D 图像上。在计算机模拟中将虚拟板连接到桡骨远端，并在矢状面上调整板。在前后位 X 线片中，测量了钢板与桡骨远端 (DPR) 之间的距离。在矢状面上，测量了掌侧月骨小面 (VLF) 的高度和每个锁定螺钉孔的骨板距离。

结果

在 VLF 高度和 DPR 之间以及 VLF 高度和 VCA 之间观察到了显着的相关性。尺骨螺钉孔处的骨板距离明显小于其他螺钉孔。

讨论

我们的研究表明，VLF 越高，VLP 越接近。板适合尺侧的骨表面，而桡侧在板和骨之间有更多空间。

证据等级

三、诊断级。