Background: 

Injuries to the anterior cruciate ligament and posterior cruciate ligament are common, and often are treated with reconstruction. Limited quantitative data are available describing material properties of grafts used for reconstructions such as the bone-patellar tendon-bone (BPTB), hamstring tendon (HS), and quadriceps tendon (QT). The purpose of this study was to quantify and compare microstructural and mechanical properties of BPTB, HS, and QT grafts.

Methods: 

Forty specimens (13 BPTB, 13 HS, and 14 QT grafts) from 24 donors were used. Specimens were subjected to preconditioning, stress relaxation, and ramp to failure. Mechanical parameters were calculated for each sample, and polarization imaging was used to evaluate the direction and strength of collagen fiber alignment during testing.

Results: 

QT had the largest modulus values, and HS had the smallest. BPTB exhibited the least disperse collagen organization, while HS were the least strongly aligned. Microstructural properties showed more strongly aligned collagen with increasing load for all grafts. All tissues showed stress relaxation and subtle microstructural changes during the hold period.

Conclusions: 

The mechanical and microstructural properties differed significantly among BPTB, HS, and QT grafts. QT exhibited the largest moduli and greatest strength of collagen alignment, while HS had the smallest moduli and least strongly aligned collagen.

Clinical Relevance: 

This study identified mechanical and microstructural differences among common grafts and between these grafts and the cruciate ligaments they replace. Further research is needed to properly interpret the clinical relevance of these differences.

中文翻译：

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十字韧带重建常用的接枝的微观结构和力学性能。

背景： 

前十字韧带和后十字韧带的损伤是常见的，并且经常用重建治疗。有限的定量数据可用于描述用于重建的移植物的材料特性，例如骨-腱（BPTB），绳肌腱（HS）和股四头肌腱（QT）。这项研究的目的是量化和比较BPTB，HS和QT移植物的微结构和力学性能。

方法： 

使用了来自24个捐献者的40个标本（13个BPTB，13个HS和14个QT移植物）。样品进行了预处理，应力松弛和破坏。计算每个样品的机械参数，并使用极化成像评估测试过程中胶原纤维排列的方向和强度。

结果： 

QT的模量值最大，HS的模量值最小。BPTB表现出的胶原组织分散最少，而HS排列最不牢固。微观结构特性显示，随着所有移植物负载的增加，胶原蛋白排列更紧密。在保持期间，所有组织均显示出应力松弛和微细微的结构变化。

结论： 

BPTB，HS和QT移植物之间的机械和微观结构性质差异显着。QT具有最大的模量和最大的胶原蛋白排列强度，而HS具有最小的模量和最不强烈的胶原蛋白排列。

临床相关性： 

这项研究确定了普通移植物之间以及这些移植物和它们所取代的十字韧带之间的机械和微观结构差异。需要进一步研究以正确解释这些差异的临床意义。