Basic studies on remodeling of fibrous tissues and their application to reconstruction of ligaments

1.考虑组织重塑的韧带重建器械设计使用由稀疏排列的纤维组成的聚酯织物作为人工韧带的模型移植物。生物学固定有望通过自发性骨长入纤维间隙实现。采用兔模型进行实验性前交叉韧带重建。力学测试和组织学测量表明，几丁质涂层移植物的附着强度和骨面积显著较大。从而成功实现生物学固定，为ACL重建提供了可能性.利用胶原纤维的引导重塑对经皮器械和牙科种植体进行生物固定。开发了模型装置，实现了周围软纤维组织的自发锚定。用大鼠背部皮肤进行的植入试验表明， ...更多信息 所有没有锚定结构的样本都从皮肤脱落，而配备有锚定结构的样本则没有。此外，组织学观察显示胶原纤维的自发锚定。预期这种自发锚定对于经皮装置和牙科植入物是有益的。在机械刺激下的软纤维组织的体外重塑在静态拉伸的机械刺激下培养大鼠的股骨筋膜，其是围绕肌肉的薄纤维软组织，其中胶原纤维的取向可以用光学显微镜监测。无负荷培养时，纤维的取向变得随机，负荷-位移曲线上的趾区消失。首先，进行增量小拉伸的样本显示高度对齐的胶原纤维和延伸的脚趾区域。另一方面，经受大拉伸的组织显示出对齐的胶原纤维和小脚趾区域。因此，适当幅度的机械刺激诱导胶原纤维的重新排列和机械性能的过继性变化，而大的刺激不触发重塑。少

1. Design of devices for ligament reconstruction considering the tissue remodeling Polyester fabrics composed of sparsely aligned fibers were utilized as the model grafts for the artificial ligaments. the biological fixation was expected to be realized through the spontaneous bone ingrowth into the space between fibers. experimental anterior cruciate ligament reconstruction was performed with using the rabbit model. the mechanical test and histometric measurement demonstrated that the attachment strength and amount of bone area were significantly large in the group of chitin-coated grafts. thus biological fixation was successfully realized and the possibility of ACL reconstruction was demonstrated.2. Biological fixation of percutaneous devices and dental implants with use of the guided remodeling of collagen fibers. Model devices were developed to which spontaneous anchoring of surrounding soft fibrous tissue was realized. implantation test with using rat's hind skin demonstrated the a … More ll specimens without anchoring structure dropped out of skin, whereas the specimens equipped with the anchoring structure did not Further, histological observation revealed the spontaneous anchoring of collagen fibers. such spontaneous anchoring is expected to be beneficial for percutaneous devices and dental implants.3. In vitro remodeling of soft fibrous tissues under mechanical stimuli Femoral fascia of rat, a thin fibrous soft tissue surrounding muscle, in which orientation of collagen fibers can be monitored with a light microscope was cultured under the mechanical stimuli of static stretching. In case of the culture free from load, the orientation of fibers became random, and the toe region in the load-displacement curve disappeared. Contrarily, the specimens subjected to incremental small stretching demonstrated highly aligned collagen fibers and extended toe region. On the other hand, the tissue subjected to a large stretch demonstrated aligned collagen fibers and small toe region. Thus suitable magnitude of mechanical stimuli induced the realignment of collagen fibers and adoptive change of mechanical properties, whereas large stimuli do not trigger remodeling. Less