Department of Biomedical Engineering and Physics, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands.
Department of Plastic, Reconstructive and Hand Surgery, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands.
Int J Comput Assist Radiol Surg. 2018 Apr;13(4):507-518. doi: 10.1007/s11548-017-1682-6. Epub 2017 Nov 6.
Utilization of 3D-printed patient-specific surgical guides is a promising navigation approach for orthopedic surgery. However, navigation errors can arise if the guide is not correctly positioned at the planned bone location, compromising the surgical outcome. Quantitative measurements of guide positioning errors are rarely reported and have never been related to guide design and underlying bone anatomy. In this study, the positioning accuracy of a standard and an extended guide design with lateral extension is evaluated at different fitting locations (distal, mid-shaft and proximal) on the volar side of the radius.
Four operators placed the surgical guides on 3D-printed radius models obtained from the CT scans of six patients. For each radius model, every operator positioned two guide designs on the three fitting locations. The residual positioning error was quantified with a CT-based image analysis method in terms of the mean target registration error (mTRE), total translation error ([Formula: see text]) and total rotation error ([Formula: see text]) by comparing the actual guide position with the preoperatively planned position. Three generalized linear regression models were constructed to evaluate if the fitting location and the guide design affected mTRE, [Formula: see text] and [Formula: see text].
mTRE, [Formula: see text] and [Formula: see text] were significantly higher for mid-shaft guides ([Formula: see text]) compared to distal guides. The guide extension significantly improved the target registration and translational accuracy in all the volar radius locations ([Formula: see text]). However, in the mid-shaft region, the guide extension yielded an increased total rotational error ([Formula: see text]).
Our study demonstrates that positioning accuracy depends on the fitting location and on the guide design. In distal and proximal radial regions, the accuracy of guides with lateral extension is higher than standard guides and is therefore recommended for future use.
使用 3D 打印的患者专用手术导板是骨科手术中一种很有前途的导航方法。然而，如果导板没有正确放置在计划的骨位置上，导航误差就会出现，从而影响手术结果。很少有报道对导板定位误差进行定量测量，而且这些报道从未与导板设计和基础骨解剖相关联。在这项研究中，评估了标准和带有侧向延伸的加长导板设计在桡骨掌侧不同适配位置（远端、中段和近端）的定位准确性。
4 名操作员将手术导板放置在从 6 名患者 CT 扫描获得的 3D 打印桡骨模型上。对于每个桡骨模型，每个操作员在三个适配位置上放置两种导板设计。通过将实际导板位置与术前计划位置进行比较，使用基于 CT 的图像分析方法来量化残余定位误差，以平均目标注册误差（mTRE）、总平移误差([Formula: see text])和总旋转误差([Formula: see text])表示。构建了三个广义线性回归模型来评估适配位置和导板设计是否影响 mTRE、[Formula: see text]和[Formula: see text]。
与远端导板相比，中段导板的 mTRE、[Formula: see text]和[Formula: see text]显著更高（[Formula: see text]）。导板延伸在所有桡骨掌侧位置都显著提高了目标注册和平移精度（[Formula: see text]）。然而，在中段区域，导板延伸导致总旋转误差增加（[Formula: see text]）。
我们的研究表明，定位准确性取决于适配位置和导板设计。在远端和近端桡骨区域，带有侧向延伸的导板的准确性高于标准导板，因此推荐在未来使用。
