AO Research Institute Davos, Davos, Switzerland.
Department of Surgery, Cantonal Hospital Graubuenden, Chur, Switzerland.
J Orthop Trauma. 2023 May 1;37(5):243-248. doi: 10.1097/BOT.0000000000002552.
To evaluate the biomechanical performance of the intramedullary TFN-ADVANCED Proximal Femoral Nailing System (TFNA) versus the extramedullary Femoral Neck System (FNS) for fixation of simple pertrochanteric fractures in a human cadaveric model.
Ten human cadaveric femoral pairs were implanted pairwise with either TFNA or FNS. A simple pertrochanteric fracture OTA/AO 31-A1 was created and all specimens were biomechanically tested under progressively increasing cyclic loading until failure. Interfragmentary and bone-implant movements were monitored by motion tracking.
Axial stiffness was comparable between TFNA and FNS, P = 0.34. Similarly, varus deformation, femoral head rotation around neck axis and implant migration remained without significant differences between TFNA and FNS after 3000 cycles (800 N peak load), P ≥ 0.10. However, cycles to 15-mm leg shortening were significantly higher for TFNA versus FNS, P < 0.01.
From a biomechanical perspective, with its current design, FNS does not seem to be a valid alternative to TFNA for treatment of simple pertrochanteric fractures.
评估髓内 TFN-ADVANCED 股骨近端髓内钉系统（TFNA）与髓外股骨颈系统（FNS）治疗简单股骨转子间骨折的生物力学性能。
将 10 对人体股骨标本成对植入 TFNA 或 FNS。创建一个简单的股骨转子间骨折 OTA/AO 31-A1，并在逐渐增加的循环载荷下对所有标本进行生物力学测试，直至失效。通过运动跟踪监测断端间和骨-植入物的运动。
轴向刚度在 TFNA 和 FNS 之间具有可比性，P = 0.34。同样，在 3000 次循环（800 N 峰值载荷）后，TFNA 和 FNS 之间的内翻变形、股骨头围绕颈轴的旋转和植入物迁移也没有显著差异，P ≥ 0.10。然而，TFNA 达到 15mm 腿缩短的循环次数明显高于 FNS，P < 0.01。
从生物力学的角度来看，在其目前的设计下，FNS 似乎不是治疗简单股骨转子间骨折的 TFNA 的有效替代方法。
