Yetkinler Duran N, Goodman Stuart B, Reindel Eric S, Carter Dennis, Poser Robert D, Constantz Brent R
ArthroCare Corporation, Sunnyvale, CA 94085, USA.
Acta Orthop Scand. 2002 Apr;73(2):157-64. doi: 10.1080/000164702753671731.
We created three-part unstable intertrochanteric fractures in 6 pairs of aged, osteopenic, human, cadaveric femora. Fractures were reduced and fixed with a Dynamic Hip Screw (DHS) (Synthes, Paoli, PA). Two test groups were evaluated: 1. Fixation with DHS, and 2. Fixation with a DHS and calcium phosphate bone cement (Norian SRS (Skeletal Repair System)) augmentation of the fracture line and posteromedial calcar region of the proximal femur. Each femur was loaded to 1,650 N (2.5 body weight) for 10,000 cycles to simulate postoperative load transmission across the fracture construct during normal gait. The load was further increased successively by one body weight for another 10,000 cycles until failure. We evaluated fixation by measuring the amount of sliding of the lag screw of the DHS (shortening) and stiffness of the overall fracture construct (stability). SRS cement-augmented specimens had less shortening (1 mm versus 17 mm) and twice the initial construct stiffness compared to control specimens.
我们在6对老年、骨质疏松的人体尸体股骨上制造了三部分不稳定型转子间骨折。骨折复位后用动力髋螺钉（DHS）（辛迪斯公司，波利，宾夕法尼亚州）固定。评估了两个试验组：1. 用DHS固定；2. 用DHS固定并在股骨近端骨折线和后内侧骨皮质区域用磷酸钙骨水泥（诺瑞安SRS（骨骼修复系统））增强。每个股骨加载至1650 N（2.5倍体重），循环10000次，以模拟正常步态期间骨折结构上的术后负荷传递。负荷再依次增加一倍体重，再循环10000次，直至失效。我们通过测量DHS拉力螺钉的滑动量（缩短）和整个骨折结构的刚度（稳定性）来评估固定情况。与对照标本相比，SRS骨水泥增强标本的缩短量更小（1毫米对17毫米），初始结构刚度是对照标本的两倍。
