Jaenisch Max, Kohlhof Hendrik, Wirtz Dieter Christian, Schildberg Frank Alexander, Beckmann Nicholas A, Kretzer Jan Philippe, Schonhoff Mareike, Jäger Sebastian
Department for Orthopaedics and Trauma Surgery, University Hospital Bonn, 53127 Bonn, Germany.
Laboratory of Biomechanics and Implant Research, Clinic for Orthopaedics and Trauam Surgery, Heidelberg University Hospital, 69118 Heidelberg, Germany.
J Clin Med. 2021 Sep 4;10(17):4002. doi: 10.3390/jcm10174002.
The goal of this study is to evaluate the primary stability of a cementless augment-and-modular-cage system with and without the addition of cranial straps in a standardized in vitro setting. As the surrogate parameter for the evaluation of primary stability, the measurement of relative motion between the implant components themselves and the bone will be used. Acetabular revision components with a trabecular titanium augment in combination with a large fourth-generation composite left hemipelvis were assembled. These constructs were divided into two groups with (S) and without cranial straps (nS). A total of 1000 cycles was applied at each of three load levels. Relative movements (RM) between the components were measured. Load levels display a significant effect on the amount of RM at all interfaces except between shell/augment. The group assignment appears to have an effect on RM due to significantly differing means at all interfaces. Between bone/shell RM increased as load increased. NS displayed significantly more RM than S. Between shell/augment RM remained constant as load increased. Between shell/cup S showed more RM than nS while both groups' RM increased with load. We conclude a significant increase of primary stability between the shell and the bone through the addition of cranial straps. Relative motion between components (shell/cup) increases through the addition of cranial straps. A clinical impact of this finding is uncertain and requires further investigation. Finally, the cementless fixation of the augment against the rim-portion of the shell appears stable and compares favorably to prior investigation of different fixation techniques.
本研究的目的是在标准化的体外环境中，评估一种无骨水泥增强型模块化髋臼杯系统在添加和不添加颅骨固定带情况下的初始稳定性。作为评估初始稳定性的替代参数，将测量植入部件自身与骨骼之间的相对运动。组装了带有小梁钛增强物的髋臼翻修部件，并与大型第四代复合左半骨盆相结合。这些结构被分为两组，一组有颅骨固定带（S组），另一组没有颅骨固定带（nS组）。在三个载荷水平下，每组均施加1000次循环，并测量部件之间的相对运动（RM）。除了髋臼杯/增强物之间的界面外，载荷水平对所有界面处的RM量均有显著影响。由于所有界面处的均值存在显著差异，分组似乎对RM有影响。在骨/髋臼杯之间，RM随着载荷增加而增加。nS组的RM显著多于S组。在髋臼杯/增强物之间，RM随着载荷增加保持不变。在髋臼杯/髋臼之间，S组的RM多于nS组，且两组的RM均随载荷增加。我们得出结论，通过添加颅骨固定带，髋臼杯与骨骼之间的初始稳定性显著提高。通过添加颅骨固定带，部件（髋臼杯/髋臼）之间的相对运动增加。这一发现的临床影响尚不确定，需要进一步研究。最后，增强物与髋臼杯边缘部分的无骨水泥固定似乎是稳定的，与先前对不同固定技术的研究相比具有优势。
