Decker Sebastian, Krämer Manuel, Marten Anna-Katharina, Pfeifer Ronny, Wesling Volker, Neunaber Claudia, Hurschler Christof, Krettek Christian, Müller Christian W
Trauma Department, Hannover Medical School, Hannover, Germany.
Laboratory for Biomechanics and Biomaterials, Hannover Medical School, Hannover, Germany.
Technol Health Care. 2015;23(4):463-74. doi: 10.3233/THC-150912.
Inverse dynamization has recently been proposed for the treatment of tibia non-unions. Nickel-titanium (NiTi) shape memory alloys (SMAs) may provide an opportunity for contactless non-invasive alteration of the stiffness of an implant after surgery.
The aim of this pilot study was to analyze the feasibility of the one way shape memory effect in a large animal as well as the feasibility of our ovine large animal fracture model.
A tibia osteotomy was performed in three sheep, followed by NiTi plate osteosynthesis in two cases and standard locking compression plate (LCP) osteosynthesis in one sheep. Contactless induction heating was performed after 3 weeks in order to alter the stiffness of the NiTi plates. Euthanasia was followed by biomechanical analysis after 8 weeks.
Successful change of configuration through contactless induction heating was shown in both SMA plates by image intensifier control. Although large differences in bending and torsional stiffness were observed between the operated and contralateral tibia, the sheep ambulated almost normally at six weeks post-operative.
We were able to trigger the one way shape memory effect which non-invasively altered the stiffness of the plate osteosynthesis.
最近有人提出反向动力化用于治疗胫骨不愈合。镍钛（NiTi）形状记忆合金（SMA）可能为术后非侵入性地改变植入物刚度提供机会。
本初步研究的目的是分析单向形状记忆效应在大型动物中的可行性以及我们的绵羊大型动物骨折模型的可行性。
对三只绵羊进行胫骨截骨术，其中两例采用镍钛板内固定，一例采用标准锁定加压钢板（LCP）内固定。3周后进行非接触式感应加热以改变镍钛板的刚度。8周后实施安乐死并进行生物力学分析。
通过影像增强器控制显示，两种形状记忆合金板均通过非接触式感应加热成功改变了形态。尽管手术侧和对侧胫骨之间在弯曲和扭转刚度上存在很大差异，但绵羊在术后六周几乎能正常行走。
我们能够触发单向形状记忆效应，该效应非侵入性地改变了钢板内固定的刚度。
