Qu Jin, Thoreson Andrew R, An Kai-Nan, Amadio Peter C, Zhao Chunfeng
Department of Orthopedic Surgery, Mayo Clinic, 200 First Street SW, Rochester, MN 55905 USA.
Department of Orthopedic Surgery, Mayo Clinic, 200 First Street SW, Rochester, MN 55905 USA.
J Biomech. 2015 Jul 16;48(10):1811-6. doi: 10.1016/j.jbiomech.2015.04.041. Epub 2015 May 6.
The knee joint is generally characterized by very low friction and high wear resistance. Several previous studies have compared ACL with the commonly used allografts from tensile properties perspective. No study has reported about the graft tendons from a frictional perspective, which is an important parameter for ACL functional performance. Twenty hind legs were used to harvest FDP tendon, ACL, ACH, and patellar tendon. Samples were evaluated with surface friction testing, indentation testing for tendon compressive moduli, lubricin immunohistochemistry, and histologic analysis. Frictional force of FDP tendon and ACL was significantly less than that of patellar tendon and ACH at first and fifth cycles. At the tenth cycle, the FDP tendon, ACL, and ACH showed significantly less frictional force than patellar tendon; after 100 cycles, the FDP tendon and ACL showed significantly less frictional force than patellar tendon. The compressive moduli of the FDP tendon, ACL, and ACH were significantly greater than that of patellar tendon. Histologic results showed that FDP tendon and ACL had a smooth surface with a thin layer of epitenon cells; patellar tendon and ACH had a rough surface and a layer of paratenon. Lubricin was found on the surface and extracellular matrix of FDP tendon and ACL. There was only limited lubricin expression on the surface and extracellular matrix of the ACH and patellar tendon. The FDP tendon has friction force and lubricin expression similar to those of native ACL. However, patellar tendon and ACH show higher friction force and less lubricin expression than ACL.
膝关节通常具有极低的摩擦力和高耐磨性。先前已有多项研究从拉伸性能角度将前交叉韧带（ACL）与常用的同种异体移植物进行了比较。但尚无研究从摩擦角度报道移植物肌腱情况，而摩擦是ACL功能表现的一个重要参数。使用20条后腿来获取指深屈肌（FDP）肌腱、ACL、跟腱（ACH）和髌腱。对样本进行表面摩擦测试、肌腱压缩模量的压痕测试、润滑素免疫组织化学和组织学分析。在第一个和第五个循环时，FDP肌腱和ACL的摩擦力明显小于髌腱和ACH。在第十个循环时，FDP肌腱、ACL和ACH的摩擦力明显小于髌腱；在100个循环后，FDP肌腱和ACL的摩擦力明显小于髌腱。FDP肌腱、ACL和ACH的压缩模量明显大于髌腱。组织学结果显示，FDP肌腱和ACL表面光滑，有一层薄的腱外膜细胞；髌腱和ACH表面粗糙，有一层腱旁组织。在FDP肌腱和ACL的表面及细胞外基质中发现了润滑素。在ACH和髌腱的表面及细胞外基质中，润滑素表达有限。FDP肌腱的摩擦力和润滑素表达与天然ACL相似。然而，髌腱和ACH的摩擦力高于ACL，润滑素表达则少于ACL。
