2023-06-16 スイス連邦工科大学ローザンヌ校(EPFL)
◆糸の物質特性や結び目の張力、摩擦、結び目の数などが結び目の強度に関係しています。予測モデルを用いた結び目の安定な作成や糸の材料開発にも応用できると期待されています。
<関連情報>
- https://actu.epfl.ch/news/study-reveals-mechanics-of-the-ideal-surgical-knot/
- https://www.science.org/doi/10.1126/sciadv.adg8861
手術用結び目の強度は、摩擦と弾力性の間の重要な相互作用に関与している。 The strength of surgical knots involves a critical interplay between friction and elastoplasticity
Paul Johanns,Changyeob Baek,Paul Grandgeorge,Samia Guerid,Shawn A. Chester and Pedro M. Rei
Science Advances Published:7 Jun 2023
DOI:https://doi.org/10.1126/sciadv.adg8861
Abstract
Knots are the weakest link in surgical sutures, serving as mechanical ligatures between filaments. Exceeding their safe operational limits can cause fatal complications. The empirical nature of present guidelines calls for a predictive understanding of the mechanisms underlying knot strength. We identify the primary ingredients dictating the mechanics of surgical sliding knots, highlighting the previously overlooked but critical effect of plasticity and its interplay with friction. The characterization of surgeon-tied knots reveals the relevant ranges of tightness and geometric features. Using model experiments coupled with finite element simulations, we uncover a robust master curve for the target knot strength versus the tying pre-tension, number of throws, and frictional properties. These findings could find applications in the training of surgeons and robotic-assisted surgical devices.
