Gerhardt Michael B, Assenmacher Benjamin S, Chahla Jorge
Cedars-Sinai Kerlan-Jobe Institute, Santa Monica, California, USA.
Orthop J Sports Med. 2019 Feb 5;7(2):2325967118824149. doi: 10.1177/2325967118824149. eCollection 2019 Feb.
Despite an abundance of literature regarding construct strength for a myriad of anchors and anchor configurations in the shoulder, there remains a paucity of biomechanical studies detailing the efficacy of these implants for proximal hamstring repair.
To biomechanically evaluate the ultimate failure load and failure mechanism of knotless and knotted anchor configurations for hamstring repair.
Controlled laboratory study.
A total of 17 cadaveric specimens divided into 3 groups composed of intact hamstring tendons as well as 2 different anchor configurations (all-knotted and all-knotless) underwent first cyclic loading and subsequent maximal loading to failure. This protocol entailed a 10-N preload, followed by 100 cycles incrementally applied from 20 to 200 N at a frequency of 0.5 Hz, and ultimately followed by a load to failure with a loading rate of 33 mm/s. The ultimate failure load and mechanism of failure were recorded for each specimen, as was the maximal displacement of each bone-tendon interface subsequent to maximal loading. Analysis of variance was employed to calculate differences in the maximal load to failure as well as the maximal displacement between the 3 study groups. Holm-Sidak post hoc analysis was applied when necessary.
The all-knotless suture anchor construct failed at the highest maximal load of the 3 groups (767.18 ± 93.50 N), including that for the intact tendon group (750.58 ± 172.22 N). There was no statistically significant difference between the all-knotless and intact tendon groups; however, there was a statistically significant difference in load to failure when the all-knotless construct was compared with the all-knotted technique (549.56 ± 20.74 N) ( = .024). The most common mode of failure in both repair groups was at the suture-tendon interface, whereas the intact tendon group most frequently failed via avulsion of the tendon from its insertion site.
Under biomechanical laboratory testing conditions, proximal hamstring repair using all-knotless suture anchors outperformed the all-knotted suture anchor configuration with regard to elongation during cyclic loading and maximal load to failure. Failure in the all-knotted repair group was at the suture-tendon interface in most cases, whereas the all-knotless construct failed most frequently at the musculotendinous junction.
No biomechanical studies have clearly identified the optimal anchor configuration to avert proximal hamstring repair failure. Delineating this ideal suture anchor construct and its strength compared with an intact hamstring tendon may alter the current standards for postoperative rehabilitation, which remain extremely conservative and onerous for these patients.
尽管有大量关于肩部多种锚钉及锚钉配置的结构强度的文献，但详细阐述这些植入物用于腘绳肌近端修复效果的生物力学研究仍然匮乏。
对用于腘绳肌修复的无结和有结锚钉配置的极限破坏载荷及破坏机制进行生物力学评估。
对照实验室研究。
总共17具尸体标本被分为3组，包括完整的腘绳肌腱以及2种不同的锚钉配置（全有结和全无结），先进行循环加载，随后进行直至破坏的最大加载。该方案包括10 N的预加载，接着以0.5 Hz的频率从20 N递增至200 N进行100次循环，最终以33 mm/s的加载速率加载直至破坏。记录每个标本的极限破坏载荷、破坏机制以及最大加载后每个骨 - 肌腱界面的最大位移。采用方差分析计算3个研究组之间最大破坏载荷以及最大位移的差异。必要时应用霍尔姆 - 西德克事后分析。
全无结缝线锚钉结构在3组中以最高的最大载荷破坏（767.18±93.50 N），包括完整肌腱组（750.58±172.22 N）。全无结组与完整肌腱组之间无统计学显著差异；然而，将全无结结构与全有结技术（549.56±20.74 N）比较时，破坏载荷有统计学显著差异（P = 0.024）。两个修复组最常见的破坏模式是在缝线 - 肌腱界面，而完整肌腱组最常见的破坏是肌腱从其附着点撕脱。
在生物力学实验室测试条件下，在循环加载期间的伸长和极限破坏载荷方面，使用全无结缝线锚钉进行腘绳肌近端修复优于全有结缝线锚钉配置。全有结修复组在大多数情况下的破坏发生在缝线 - 肌腱界面，而全无结结构最常发生在肌腱 - 肌肉交界处破坏。
尚无生物力学研究明确确定避免腘绳肌近端修复失败的最佳锚钉配置。与完整的腘绳肌腱相比，确定这种理想的缝线锚钉结构及其强度可能会改变目前术后康复的标准，目前的标准对这些患者来说仍然极其保守且繁重。
