Ethicon, Inc., Cincinnati, OH.
Surg Technol Int. 2022 May 19;40:97-103. doi: 10.52198/22.STI.40.GS1550.
Since its adoption as a surgical technique over a half-century ago, stapling has continually undergone improvements, both in the devices used and in our understanding of tissue mechanics. To best design and use stapling devices, it is beneficial to have an intimate knowledge of the response of tissue to compression and stapling dynamics. This paper provides the relevant background in the field of biomechanics, and in particular addresses the viscoelastic behavior of soft tissues under compression. Biomechanics of Stapling: The change in shape of a solid, or strain, is related to the load applied, or stress. Biological tissues are known to have non-linear relationships between stress and strain, and generally the relationships are anisotropic (dependent upon direction). Further complicating matters, there is typically a time-dependency to the relationship for compression and recovery, resulting in viscoelastic behavior. Hence both the amount and rate of compressive force applied can be expected to impact the outcome of stapling.
The growth of the laparoscopic use of staples has increased the difficulty of device design, as precise control of compression is problematic in extended length staplers. Progressive firing along the cartridge and multi-stage compression have both been found to be beneficial in providing the uniform force needed to produce well-formed staples. Such technical advances can reduce stresses within the stapler, preventing deformation of the stapler arm and undesirable strain in the tissue. Current research includes understanding the effects of changing the rate of compression on staple formation with the hope that further improvements can be achieved in this ever-fruitful method of tissue apposition.
自半个多世纪前被采用为一种手术技术以来，吻合器在器械使用和我们对组织力学的理解方面不断得到改进。为了更好地设计和使用吻合器，深入了解组织对压缩和吻合器动态的反应是有益的。本文提供了生物力学领域的相关背景知识，特别是介绍了软组织在压缩下的粘弹性行为。吻合器的生物力学：固体的形状变化，或应变，与所施加的载荷，或应力有关。众所周知，生物组织在应力和应变之间存在非线性关系，并且通常关系是各向异性的（取决于方向）。进一步复杂化的是，对于压缩和恢复，关系通常具有时间依赖性，导致粘弹性行为。因此，施加的压缩力的大小和速率都可能会影响吻合的结果。
随着腹腔镜中吻合器使用的增加，器械设计的难度也增加了，因为在长型吻合器中精确控制压缩是有问题的。沿管筒的逐步击发和多阶段压缩都被发现有助于提供产生成型良好的吻合所必需的均匀力。这些技术进步可以减少吻合器内的应力，防止吻合器臂变形和组织中出现不良应变。目前的研究包括了解改变压缩速率对吻合形成的影响，希望在这种不断产生成果的组织贴合方法中能够进一步改进。
