Department of Orthopaedics, Sichuan Provincial People's Hospital, University of Electronic Science and Technology of China, Chengdu, China.
J Orthop Res. 2023 Jul;41(7):1546-1554. doi: 10.1002/jor.25503. Epub 2022 Dec 20.
To determine the optimal position of three cannulated screws in an inverted triangle pattern for internal fixation of femoral neck fractures, including the apex-subchondral bone distance, computed tomography (CT) images of the hip were processed using the MIMICS (Materialize Interactive Medical Image Control System) Research software. Points adjacent to the inferior, anterosuperior, and posterior cortex of the femoral neck were selected on the axial view. Subsequently, the positions of these points were adjusted to maximize the area between them, and splines were drawn in the coronal and sagittal planes to represent the cannulated screws. Finally, the virtual anteroposterior and lateral fluoroscopy images of the proximal femur and splines were created and the parameters calculated. Finite element analysis showed this fixation scheme provides stronger fracture support and stability. Twenty patients with femoral neck fractures (Modified group), with the area and perimeter of the triangle formed on axial postoperative CT images, including the shortest distance from the tip of the screw to the subchondral bone was compared with 23 matched patients for whom the conventional inverted isosceles triangle configuration of screws for internal fixation was used (Conventional group). The area and perimeter of the stabilization screws were larger, with a shorter apex-subchondral bone distance for the Modified group. There was no incidence of screw penetration in the femoral neck or head in either group, and all fractures healed within a follow-up period of 10 months. The modified screw placement method is simple and safe and provides greater fracture stability than the conventional empirical method of fixation.
为了确定三枚空心螺钉在倒三角形模式下固定股骨颈骨折的最佳位置，包括尖端-软骨下骨距离，使用 MIMICS（Materialize Interactive Medical Image Control System）研究软件对髋关节的 CT 图像进行处理。在轴位视图上选择靠近股骨颈下、前上和后皮质的点。然后，调整这些点的位置以最大化它们之间的区域，并在冠状面和矢状面绘制样条线以代表空心螺钉。最后，创建了近端股骨的虚拟前后透视图像和样条线，并计算了参数。有限元分析表明，这种固定方案提供了更强的骨折支撑和稳定性。比较了 20 名股骨颈骨折患者（改良组）术后 CT 图像轴位上形成的三角形的面积和周长，包括螺钉尖端到软骨下骨的最短距离，与 23 名接受常规空心螺钉固定的患者（常规组）进行比较。改良组的稳定螺钉的面积和周长更大，尖端-软骨下骨距离更短。两组均未发生股骨颈或股骨头内螺钉穿透，所有骨折均在 10 个月的随访期内愈合。改良螺钉的放置方法简单、安全，提供的骨折稳定性优于常规经验性固定方法。
