Caldeira Fátima Maria C, Rahal Sheila C, Cassanego Guilherme R, Ribeiro Celso R, Serrato Sergio A A, Mele Carlos E, Masseran Paulo
Department of Veterinary Surgery and Animal Reproduction, School of Veterinary Medicine and Animal Science-São Paulo State University (UNESP), Rubião Júnior s/n, Botucatu, São Paulo, Brazil.
LEMM-Laboratório de Ensaios Mecânicos, Jaú, São Paulo, Brazil.
Vet Comp Orthop Traumatol. 2025 Jan;38(1):18-24. doi: 10.1055/s-0044-1788802. Epub 2024 Aug 1.
To evaluate the in vitro mechanical properties of basilar fractures of the femoral neck stabilized with two or three titanium-cannulated screws in dogs.
Ex vivo study.
Cadaveric canine femur ( = 21).
The bones were divided as follows: Group 1: control (no osteotomy); Group 2: osteotomy and stabilization with two cannulated screws; and Group 3: osteotomy and stabilization with three cannulated screws. All groups were tested with destructive axial compression with load applied to the femoral head. The stiffness, load, and displacement were evaluated at the failure of Group 1, and the yield load and displacement of Groups 2 and 3.
The placement of the three cannulated screws was more demanding than two cannulated screws because of the risk of cortical perforation, especially in the trochanteric fossa area. The smaller the width of the femoral neck, the higher the risk of cortical bone wall perforation. The intact control bones were stiffer (674 N/mm) than both the two-screw repair (90 N/mm) and three-screw repair (120 N/mm) groups ( < 0.05). The failure load was greatest for Group 1 (2692 N). The yield loads for Groups 3 and 2 were 586 and 303 N, respectively. There was no difference between groups for displacement.
In vitro cadaveric models of femoral neck basilar fractures repaired with three cannulated screws were significantly stronger than two cannulated screws, but the clinical efficacy must be evaluated by comparing them in vitro with noncannulated stainless steel screws.
评估在犬类中使用两枚或三枚空心钛螺钉固定股骨颈基底骨折后的体外力学性能。
体外研究。
犬类尸体股骨（n = 21）。
将骨骼分为以下几组：第1组：对照组（未进行截骨术）；第2组：截骨并用两枚空心螺钉固定；第3组：截骨并用三枚空心螺钉固定。所有组均通过对股骨头施加轴向压缩力直至破坏来进行测试。在第1组破坏时评估刚度、载荷和位移，在第2组和第3组评估屈服载荷和位移。
由于存在皮质穿孔风险，尤其是在转子窝区域，三枚空心螺钉的置入比两枚空心螺钉要求更高。股骨颈宽度越小，皮质骨壁穿孔风险越高。完整的对照骨骼比双螺钉修复组（90 N/mm）和三螺钉修复组（120 N/mm）更硬（674 N/mm）（P < 0.05）。第1组的破坏载荷最大（2692 N）。第3组和第2组的屈服载荷分别为586 N和303 N。各组之间的位移无差异。
用三枚空心螺钉修复股骨颈基底骨折的体外尸体模型比用两枚空心螺钉修复的模型显著更强，但临床疗效必须通过将它们与非空心不锈钢螺钉在体外进行比较来评估。
