Hak David J, Neiman Rafael, Hazelwood Scott
Denver Health / University of Colorado, Denver, Colorado.
Curr Orthop Pract. 2010 Aug 12;21(4):385-389. doi: 10.1097/BCO.0b013e3181d73bae.
The purpose of this study was to examine the influence of proximal retrograde intramedullary nail position on proximal femoral strain, since stress risers occurring at the end of an implant can increase fracture risk. METHODS: Proximal femoral strains during axial and torsional loading were measured in composite Sawbone femurs after placement of retrograde intramedullary nails that ended at three different locations (2 cm proximal, 4 cm distal, and at the level of the lesser trochanter). RESULTS: No statistically significant difference was found between the axial or torsional strain observed in the intact femur and that seen after placement of a retrograde femoral nail ending at any of the three positions. Gages proximal to the nail tip demonstrated higher strains than the strains for the intact femur when compared with gages distal to the nail tip. CONCLUSION: The ending location of a retrograde nail in the proximal femur does not appear to significantly alter strain in the proximal femur under the axial and torsional loading methods used in the study.
本研究的目的是检查逆行髓内钉近端位置对股骨近端应变的影响，因为植入物末端出现的应力集中会增加骨折风险。方法：在复合Sawbone股骨中，放置在三个不同位置（小转子水平近端2 cm、小转子水平远端4 cm以及小转子水平）结束的逆行髓内钉后，测量轴向和扭转载荷期间的股骨近端应变。结果：在完整股骨中观察到的轴向或扭转载荷与在三个位置中任何一个位置结束的逆行股骨钉放置后观察到的轴向或扭转载荷之间，未发现统计学上的显著差异。与钉尖远端的应变片相比，钉尖近端的应变片显示出比完整股骨的应变更高的应变。结论：在本研究使用的轴向和扭转载荷方法下，逆行钉在股骨近端的结束位置似乎不会显著改变股骨近端的应变。
