Manufacturing and Automation Research Center, Koç University, Istanbul, Turkey.
Department of Orthopaedics and Traumatology, Koç University Hospital, Istanbul, Turkey.
Acta Orthop Traumatol Turc. 2023 Jul;57(4):134-140. doi: 10.5152/j.aott.2023.22175.
This study aimed to introduce a method to extract the 3-dimensional spatial position of the femoral head implant from 2-dimensional fluoroscopic projections, allowing surgeons to assess fixation much more accurately and prevent cut-out complications in proximal femoral nailing.
To define a safety region for the tip in the femoral head, a novel 3-dimensional distance-based risk parameter called TSD3D was introduced. An intersection algorithm was developed that solely takes the fluoroscopic anteroposterior and lateral distances to reveal the 3-dimensional location of the screw or Kirschner wire tip, enabling the utilization of the 3-dimensional parameter. Orthogonal per- spectives of 6 femur proximal bone substitutes with randomly inserted Kirschner wires were imaged under fluoroscopy. The developed algorithm was used to calculate the implant tip location in 3-dimensional from 2-dimensional images for each case. Algorithm accuracy was validated with the computed tomography-obtained 3-dimensional models of the same femur substitutes.
The newly introduced risk parameter successfully visualizes 3-dimensional safety regions. Utilizing the 2-dimensional fluoro- scopic distances as inputs to the algorithm, the 3-dimensional position of the implanted Kirschner wire tip is calculated with a maximum of 9.8% error for a single Cartesian-coordinate measurement comparison.
By incorporating the newly introduced 3-dimensional risk parameter, surgeons can more precisely evaluate the position of the implant and avoid cut-out complications, instead of relying solely on misleading 2-dimensional fluoroscopic projections of the femoral head.
本研究旨在介绍一种从二维透视投影中提取股骨头植入物三维空间位置的方法，使外科医生能够更准确地评估固定情况，防止股骨近端钉固定时出现切割脱出并发症。
为了定义股骨头内尖端的安全区域，引入了一种新的基于三维距离的风险参数 TSD3D。开发了一种交集算法，该算法仅使用透视前后位和侧位距离来揭示螺钉或克氏针尖端的三维位置，从而可以利用三维参数。在透视下对 6 个股骨近端骨替代物中随机插入的克氏针进行正交透视成像。对于每个病例，使用开发的算法从二维图像计算植入物尖端的三维位置。通过与相同股骨替代物的计算机断层扫描获得的三维模型验证算法的准确性。
新引入的风险参数成功地可视化了三维安全区域。利用二维荧光透视距离作为算法的输入，植入克氏针尖端的三维位置通过单点笛卡尔坐标测量比较计算，最大误差为 9.8%。
通过引入新的三维风险参数，外科医生可以更精确地评估植入物的位置，避免切割脱出并发症，而不是仅仅依赖于误导性的股骨头二维荧光透视投影。
