Background Panda Rope Bridge Technique (PRBT) was an new minimally invasive technique consisted of two bridge anchors (proximal anchors at calcaneus and distal anchors at myotendinous junction) and strong ropes (threads of the suture anchors) stretched between them, which was suitable for early accelerated rehabilitation of Achilles tendon rupture. However, the optimal knot configuration with PRBT was unknow. The purpose of this study was identify minimum number of half hitches necessary to maintain knot security for PRBT.

Methods Using an Instron device we tested the effect of different knot configuration in two kinds of suture threads (Ethibond™ #5 and Ultrabraid™ #2). According to the result of it, we put the optimal knot configuration into Part 1 with PRBT test model and Part 2 with modified PRBT test model, to evaluate whether the optimal knot configuration could complete the cyclic loading test simulated early rehabilitation.

Findings In the first part of the study, the optimal knot configuration of Ethibond™ #5 suture thread was the combination of three half hitches and one double throw half knot, and the optimal knot configuration of Ultrabraid™ #2 suture thread was the combination of five half hitches and one double throw half knot. In the second part of the study, only Ultrabraid™ #2 suture thread with optimal knot configuration had finished all test in Part 1.

Interpretation The Ultrabraid™ #2 suture thread with optimal knot configuration was suitable for PRBT with early accelerated rehabilitation after Achilles tendon repair.

背景技术熊猫绳桥技术（PRBT）是一种新的微创技术，包括两个桥锚（跟骨近端锚和肌腱交界处远侧锚）和在它们之间伸展的坚固绳索（缝合锚的线），适用于早期跟腱断裂加速康复。但是，使用PRBT的最佳结配置是未知的。这项研究的目的是确定维持PRBT结安全性所需的最少的半结。

方法我们使用Instron装置在两种缝合线（Ethibond™＃5和Ultrabraid™＃2）中测试了不同打结配置的效果。根据结果​​，将最优的结构型放入PRBT测试模型的第1部分中，并将其修改后的PRBT测试模型分为第2部分，以评估最优的结构型是否可以完成模拟早期康复的循环载荷试验。

研究结果在研究的第一部分中，Ethibond™＃5缝合线的最佳打结配置是三个半钩和一个双掷半结的组合，而Ultrabraid™＃2缝合线的最佳打结配置是五个半结和一个双掷半结。在研究的第二部分中，只有具有最佳打结配置的Ultrabraid™＃2缝合线才完成了第1部分中的所有测试。

解释具有最佳结构型的Ultrabraid™＃2缝合线适用于跟腱修复后及早加速康复的PRBT。