Objective The aim of this study was to evaluate the surgical execution of a virtual surgical plan (VSP) with three-dimensional (3D) guides against a freehand approach in the equine navicular bone using an automated in silico computer analysis technique.

Study Design Eight pairs of cadaveric forelimb specimens of adult horses were used in an ex vivo experimental study design with in silico modelling. Limbs received either a 3.5 mm cortical screw according to a VSP or using an aiming device. Using computed tomography and computer segmentation, a comparison was made between the executed screw and the planned screw using the Hausdorff distance (HD).

Results Navicular bone mean HD registration error was –0.06 ± 0.29 mm. The VSP with 3D printing demonstrated significantly superior accuracy with a mean deviation of 1.19 ± 0.42 mm compared with aiming device group (3.53 ± 1.24 mm, p = 0.0018). The VSP group was 5.0 times more likely to result in a mean aberration of less than 1.0 mm (95% confidence interval, 0.62–33.4). A 3.5 mm screw with an optimal entry point can have a maximum deviation angle of 3.23 ± 0.07, 2.70 ± 0.06 and 2.37 ± 0.10 degrees in a proximal, dorsal and palmar direction respectively, prior to violating one of the cortical surfaces.

Conclusion Procedures performed using the 3D guides have a high degree of accuracy, with minimal mean deviations (<1 mm and <1 degree) of a VSP compared with those using the conventional aiming device. The use of VSP and the HD for evaluation of orthopaedic surgeries and outcome measures shows promise for simplifying and improving surgical accuracy.

目的 本研究的目的是评价与针对在马舟骨徒手方法三维（3D）指南使用自动化的虚拟手术计划（VSP）的外科执行在计算机芯片上的计算机分析技术。

研究设计 八对成年马的尸体前肢标本被用于具有计算机模拟模型的离体实验研究设计。根据 VSP 或使用瞄准装置，四肢接受了 3.5 mm 皮质螺钉。使用计算机断层扫描和计算机分割，使用 Hausdorff 距离 (HD) 在执行的螺钉和计划的螺钉之间进行比较。

结果 舟骨平均 HD 配准误差为 –0.06 ± 0.29 mm。与瞄准装置组 (3.53 ± 1.24 mm, p  = 0.0018)相比，采用 3D 打印的 VSP 显示出显着优越的精度，平均偏差为 1.19 ± 0.42 mm 。VSP 组产生小于 1.0 mm 的平均像差的可能性高 5.0 倍（95% 置信区间，0.62-33.4）。在侵犯皮质表面之一之前，具有最佳进入点的 3.5 毫米螺钉在近端、背侧和手掌方向上的最大偏差角分别为 3.23 ± 0.07、2.70 ± 0.06 和 2.37 ± 0.10 度。

结论 与使用传统瞄准装置的程序相比，使用 3D 导向器执行的程序具有高度的准确性，VSP 的平均偏差最小（<1 毫米和 <1 度）。使用 VSP 和 HD 评估骨科手术和结果测量显示出简化和提高手术准确性的希望。