Obid Peter, Danyali Reza, Kueny Rebecca, Huber Gerd, Reichl Michael, Richter Alexander, Niemeyer Thomas, Morlock Michael, Püschel Klaus, Übeyli Hüseyin
Department of Spine and Scoliosis Surgery, Asklepios Klinik St. Georg, Hamburg, Germany.
Institute for Biomechanics, TU Hamburg-Harburg, Hamburg, Germany.
Global Spine J. 2017 Feb;7(1):47-53. doi: 10.1055/s-0036-1583945. Epub 2017 Feb 1.
Ex vivo human cadaveric study.
The development or progression of adjacent segment disease (ASD) after spine stabilization and fusion is a major problem in spine surgery. Apart from optimal balancing of the sagittal profile, dynamic instrumentation is often suggested to prevent or impede ASD. Hybrid instrumentation is used to gain stabilization while allowing motion to avoid hypermobility in the adjacent segment. In this biomechanical study, the effects of two different hybrid instrumentations on human cadaver spines were evaluated and compared with a rigid instrumentation.
Eighteen human cadaver spines (T11-L5) were subdivided into three groups: rigid, dynamic, and hook comprising six spines each. Clinical parameters and initial mechanical characteristics were consistent among groups. All specimens received rigid fixation from L3-L5 followed by application of a free bending load of extension and flexion. The range of motion (ROM) for every segment was evaluated. For the rigid group, further rigid fixation from L1-L5 was applied. A dynamic Elaspine system (Spinelab AG, Winterthur, Switzerland) was applied from L1 to L3 for the dynamic group, and the hook group was instrumented with additional laminar hooks at L1-L3. ROM was then evaluated again.
There was no significant difference in ROM among the three instrumentation techniques.
Based on this data, the intended advantage of a hybrid or dynamic instrumentation might not be achieved.
人体尸体离体研究。
脊柱稳定融合术后相邻节段疾病（ASD）的发生或进展是脊柱外科的一个主要问题。除了矢状面轮廓的最佳平衡外，通常建议使用动态内固定来预防或阻止ASD。混合内固定用于获得稳定，同时允许活动以避免相邻节段的活动过度。在这项生物力学研究中，评估了两种不同混合内固定对人体尸体脊柱的影响，并与刚性内固定进行了比较。
将18具人体尸体脊柱（T11-L5）分为三组：刚性组、动态组和钩形组，每组6具脊柱。各组的临床参数和初始力学特性一致。所有标本均接受L3-L5的刚性固定，然后施加屈伸自由弯曲载荷。评估每个节段的活动范围（ROM）。对于刚性组，施加L1-L5的进一步刚性固定。对动态组从L1到L3应用动态Elaspine系统（瑞士温特图尔Spinelab AG公司），钩形组在L1-L3处使用额外的椎板钩进行内固定。然后再次评估ROM。
三种内固定技术在ROM方面无显著差异。
基于这些数据，混合或动态内固定预期的优势可能无法实现。
