Völlner Florian, Pilsl Ulrike, Craiovan Benjamin, Zeman Florian, Schneider Michael, Wörner Michael, Grifka Joachim, Weber Markus
Department of Orthopaedic Surgery, University Medical Centre Regensburg, Asklepios Klinikum Bad Abbach, Kaiser-Karl-V-Allee 3, 93077 Bad Abbach, Germany.
Institute of Macroscopic and Clinical Anatomy, Medical University of Graz, Harrachgasse 21, 8010 Graz, Austria.
J Mech Behav Biomed Mater. 2017 Jul;71:392-396. doi: 10.1016/j.jmbbm.2017.04.009. Epub 2017 Apr 7.
The first biomechanical evaluation of new implants is usually carried out with cadavers. Fixation of Thiel-embalmed cadavers is supposed to preserve the histological structure, colour and consistency of the tissue and has a low risk of infection and toxicity. However, the biomechanical properties of Thiel-fixated tissue are still unknown. The aim of this study was to quantify the effect of the Thiel-embalming method on the elastic properties of the ligament complex of the knee compared to in vivo knees during total knee arthroplasty.
The results of biomechanical tensile tests with 10 Thiel-embalmed knees were compared with the findings of 10 patients who underwent total knee arthroplasty with a standardised knee balancer at our department. We reconstructed the force-elongation curves of the medial and lateral ligament complex and calculated the stiffness in direct correlation with overall soft tissue stability in full extension and in 90° of flexion.
All curves consisted of a non-linear part at the beginning and a linear part from about 80N onwards. In full extension, median stiffness in the cadavers was 26.6N/mm for the medial compartment and 31.6N/mm for the lateral compartment. The values for in vivo were 25.7N/mm for the medial compartment and 25.3N/mm for the lateral compartment (p=0.684 for the medial compartment and p=0.247 for the lateral compartment). In 90° of flexion, median stiffness in the cadaver group was 24.7N/mm for the medial compartment and 22.2N/mm for the lateral compartment. In vivo, median stiffness was 30.3N/mm for the medial compartment and 29.2N/mm for the lateral compartment (p=0.009 for the medial compartment and p=0.143 for the lateral compartment).
Stiffness of the medial and lateral ligament complex in the knee was comparable between Thiel-embalmed cadavers and in vivo patients during total knee arthroplasty. Thiel fixation seems to preserve the soft tissue properties similar to those in vivo.
新型植入物的首次生物力学评估通常在尸体上进行。福尔马林固定的尸体被认为能够保留组织的组织结构、颜色和质地，且感染和毒性风险较低。然而，福尔马林固定组织的生物力学特性仍然未知。本研究的目的是量化福尔马林防腐方法与全膝关节置换术中活体膝关节相比，对膝关节韧带复合体弹性特性的影响。
将10个福尔马林固定膝关节的生物力学拉伸试验结果与在我们科室使用标准化膝关节平衡器进行全膝关节置换术的10例患者的结果进行比较。我们重建了内侧和外侧韧带复合体的力-伸长曲线，并计算了与完全伸展和90°屈曲时整体软组织稳定性直接相关的刚度。
所有曲线在开始时都有一个非线性部分，从大约80N开始为线性部分。在完全伸展时，尸体内侧间室的中位刚度为26.6N/mm，外侧间室为31.6N/mm。活体的内侧间室值为25.7N/mm，外侧间室为25.3N/mm（内侧间室p=0.684，外侧间室p=0.247）。在90°屈曲时，尸体组内侧间室的中位刚度为24.7N/mm，外侧间室为22.2N/mm。在活体中，内侧间室的中位刚度为30.3N/mm，外侧间室为29.2N/mm（内侧间室p=0.009，外侧间室p=0.143）。
在全膝关节置换术中，福尔马林固定的尸体膝关节和活体患者膝关节的内侧和外侧韧带复合体刚度相当。福尔马林固定似乎能保留与活体相似的软组织特性。
