Department of Orthopedic Surgery, Mayo Clinic, Rochester, Minnesota.
J Bone Joint Surg Am. 2022 Nov 16;104(22):2000-2007. doi: 10.2106/JBJS.21.01538. Epub 2022 Aug 23.
The stability of a suture knot construct has been realized as an important parameter that affects the strength of flexor tendon repairs. A novel 2-strand-overhand-locking (TSOL) knot, which is not commonly used in the clinical setting, recently was reported to increase repair strength and to decrease tendon gliding resistance in a 2-strand repair technique. The purpose of the present study was to investigate the effect of the TSOL knot on tendon repair strength and gliding resistance compared with a typical surgical knot in both 2-strand and 4-strand repair techniques using an in vitro turkey flexor tendon model.
Sixty flexor digitorum profundus tendons from the long digit of the turkey foot were divided evenly into 4 groups and repaired with the following techniques: (1) a 2-strand modified Pennington repair with a square knot, (2) a 2-strand modified Pennington repair with a TSOL knot, (3) a 4-strand grasping cruciate repair with a square knot, and (4) a 4-strand grasping cruciate repair with a TSOL knot. Repaired tendons were tested for failure mode, gliding resistance, and repair strength at failure.
The repair strength and stiffness of the 4-strand repairs were significantly higher than those of the 2-strand repairs, regardless of knot type (p < 0.05). The repair strength at failure of the TSOL knot was significantly greater than that of the square knot in 2-strand repairs (p < 0.05) but not in 4-strand repairs. The gliding resistance of the TSOL knot was significantly decreased compared with that of the square knot in both 2-strand and 4-stand repairs (p < 0.05). With regard to failure mode, the TSOL knot was less likely to fail due to knot unravelling.
In this in vitro biomechanical study involving the use of turkey flexor tendons to compare gliding resistance and repair strength characteristics for knot-inside 2 and 4-strand repairs, the TSOL knot was associated with decreased repaired tendon gliding resistance, regardless of the number of strands used. Although the TSOL knot also increased the repair strength, the difference was only significant when 2-strand repairs were used. The results of our study support the use of the TSOL knot in the clinical setting of flexor tendon repair using 2 or 4-strand, knot-inside methods.
In surgical repair of flexor tendons, there is substantial interest in maximizing strength while minimizing friction. This study shows the potential utility of the TSOL knot to increase repair strength while decreasing gliding resistance, particularly in 2-strand repairs.
缝线结的稳定性已被认为是影响屈肌腱修复强度的一个重要参数。一种新型的双股套圈锁结（TSOL），最近在双股修复技术中报道可增加修复强度和减少肌腱滑动阻力，但在临床中并不常用。本研究旨在通过体外土耳其屈肌腱模型，比较 TSOL 结与典型手术结在双股和四股修复技术中对肌腱修复强度和滑动阻力的影响。
将 60 个来自土耳其足长趾的屈趾深肌腱均分为 4 组，分别采用以下技术修复：（1）改良的双 Pennington 修复，用方结；（2）改良的双 Pennington 修复，用 TSOL 结；（3）四股抓握十字修复，用方结；（4）四股抓握十字修复，用 TSOL 结。测试修复后的肌腱的失效模式、滑动阻力和失效时的修复强度。
无论结的类型如何（p<0.05），四股修复的修复强度和刚度均明显高于双股修复。在双股修复中，TSOL 结的失效强度明显大于方结（p<0.05），但在四股修复中则不然。与方结相比，TSOL 结在双股和四股修复中的滑动阻力均显著降低（p<0.05）。就失效模式而言，TSOL 结不易因结松解而失效。
在这项涉及使用土耳其屈肌腱的体外生物力学研究中，比较了双股和四股缝线内结的滑动阻力和修复强度特征，无论使用的股数如何，TSOL 结均与修复后肌腱滑动阻力降低有关。尽管 TSOL 结也增加了修复强度，但差异仅在使用双股修复时才具有统计学意义。我们的研究结果支持在临床中使用双股或四股缝线内结修复屈肌腱。
在屈肌腱的外科修复中，人们非常关注在最大限度地提高强度的同时最大限度地减少摩擦。本研究表明，TSOL 结具有增加修复强度和降低滑动阻力的潜力，特别是在双股修复中。
