Haynes R C, Pöll R G, Miles A W, Weston R B
School of Mechanical Engineering, University of Bath, UK.
Injury. 1997 Jun-Jul;28(5-6):337-41. doi: 10.1016/s0020-1383(97)00035-1.
The most commonly reported failure mode of sliding hip screws in published literature is cut-out of the lag screw. This study investigates the resistance to failure of the femoral head, with lag screws used in two types of sliding hip screws, the gamma locking nail (Howmedica) and the dynamic hip screw (DHS) (Synthes). The investigation consisted of biomechanical tests under static loading conditions on 12 pairs of cadaveric femoral heads, to establish the failure loads due to screw cut-out for the two implant lag screws. The gamma nail appeared to reduce the tendency to cut-out in the osteoporotic bone (soft) associated with elderly patients in whom these devices are commonly used (p < 0.05). In high density bone (hard) the gamma lag screw also appeared to be stronger, because the DHS showed a tendency to bend. The larger diameter of the gamma nail lag screw resists bending and appears to reduce the risk of cut-out compared with the DHS.
在已发表的文献中，滑动髋螺钉最常报道的失效模式是拉力螺钉穿出。本研究调查了使用两种滑动髋螺钉（伽马锁定钉（Howmedica公司）和动力髋螺钉（DHS，Synthes公司））中的拉力螺钉时股骨头的抗失效能力。该研究包括对12对尸体股骨头进行静态加载条件下的生物力学测试，以确定两种植入拉力螺钉因螺钉穿出导致的失效载荷。伽马钉似乎降低了在骨质疏松性骨（软质）中穿出的倾向，而骨质疏松性骨常见于通常使用这些器械的老年患者（p<0.05）。在高密度骨（硬质）中，伽马拉力螺钉似乎也更强，因为动力髋螺钉有弯曲的倾向。与动力髋螺钉相比，伽马钉拉力螺钉的较大直径可抵抗弯曲，似乎降低了穿出风险。
