Wähnert Dirk, Müller Marcus, Tiedemann Hendrik, Märdian Sven, Raschke Michael J, Kösters Clemens
Protestant Hospital of Bethel Foundation, Department of Trauma and Orthopaedic Surgery, Burgsteig 13, Building Gilead I, 33617, Bielefeld, Germany.
Westfaelische-Wilhelms-University Muenster, Institute for Musculoskeletal Medicine, Albert-Schweitzer-Campus 1, Building D3, 48149, Muenster, Germany.
J Orthop Translat. 2020 Feb 8;24:150-154. doi: 10.1016/j.jot.2020.01.005. eCollection 2020 Sep.
Periprosthetic fractures of the femur are an increasing problem in today's trauma and orthopaedic surgery. Owing to the hip stem, implant anchorage is very difficult in the proximal femur. This study compares two plate systems regarding their biomechanical properties and the handling in periprosthetic fracture fixation of the proximal femur.
Using eight pairs of fresh, frozen human proximal femora the Locking Compression Plate/Locking Attachment Plate construct (LCP/LAP) (group I, DePuy Synthes) was compared to the new LOQTEQ® periprosthetic distal lateral femur plate (group II, AAP Implantate AG). After implantation of press fit femoral hip stems a Vancouver B1 fracture model was used. Biomechanical testing was performed by cyclic axial loading with a constant increment of 0.1 N/cycle starting from 750 N axial loading. Every 250 cycles an a.p. x-ray was done to evaluate failure.
The Group II showed significant higher axial stiffness (+42%) compared with Group I. In addition, Group II withstood significantly more load-cycles until failure (20%). The mode of catastrophic failure was plate breakage in Group II, whereas, in Group I, all plates showed an early bending followed by plate breakage.
Both plate systems enable screw placement around hip stems. The hinge plate showed superior biomechanical results compared with the locking compression plate/locking attachment plate construct. Furthermore, the hinge plate offers variable hinges and variable angel locking making bicortical screw placement around hip stems more comfortable and safe.
The results of this study can be directly transferred to patient care. With the innovative hinge plate, the surgeon has a biomechanically superior implant, which also offers improved options for screw placement compared to a standard locking plate.
股骨假体周围骨折在当今创伤和骨科手术中是一个日益严重的问题。由于股骨柄的存在，在股骨近端进行植入物固定非常困难。本研究比较了两种钢板系统在股骨近端假体周围骨折固定中的生物力学性能和操作情况。
使用八对新鲜冷冻的人股骨近端，将锁定加压钢板/锁定附件钢板结构（LCP/LAP）（第一组，DePuy Synthes公司）与新型LOQTEQ®股骨假体远端外侧钢板（第二组，AAP Implantate AG公司）进行比较。在压配式股骨柄植入后，采用温哥华B1骨折模型。通过从750 N轴向载荷开始以0.1 N/循环的恒定增量进行循环轴向加载来进行生物力学测试。每250个循环进行一次前后位X线检查以评估失效情况。
第二组的轴向刚度比第一组显著更高（+42%）。此外，第二组在失效前承受的载荷循环次数显著更多（多20%）。灾难性失效模式在第二组为钢板断裂，而在第一组，所有钢板均早期弯曲，随后钢板断裂。
两种钢板系统都能在股骨柄周围放置螺钉。与锁定加压钢板/锁定附件钢板结构相比，铰链钢板显示出更好的生物力学结果。此外，铰链钢板提供可变铰链和可变角度锁定，使在股骨柄周围进行双皮质螺钉置入更加舒适和安全。
本研究结果可直接应用于患者护理。有了创新的铰链钢板，外科医生拥有了一种生物力学性能更优的植入物，与标准锁定钢板相比，它在螺钉置入方面也提供了更好的选择。
