Institute of Sports Medicine, Peking University Third Hospital, No. 49, North Garden Road, 100191, Haidian District, Beijing, People's Republic of China.
Knee Surg Sports Traumatol Arthrosc. 2011 Jun;19(6):1028-34. doi: 10.1007/s00167-010-1278-y. Epub 2010 Oct 7.
The increased use of allograft tissue in the reconstruction of anterior cruciate ligament has brought more focus to the effect of storage and treatment on allograft. The purpose of this study was to observe the effect of histology and biomechanics on Achilles tendon in rabbits through repeated freezing-thawing before allograft tendon transplantation. Rabbit Achilles tendons were harvested and processed according to the manufacture's protocol of tissue bank, and freezing-thawing was repeated three times (group 1) and ten times (group 2). Those received only one cycle were used as controls. Then, tendons in each group were selected randomly to make for histological observations and biomechanics test. Histological observation showed that the following changes happened as the number of freezing-thawing increased: the arrangement of tendon bundles and collagen fibrils became disordered until ruptured, cells disrupted and apparent gaps appeared between tendon bundle because the formation of ice crystals. There were significant differences between the experimental and control groups in the values of maximum load, energy of maximum load and maximum stress, whereas no significant differences existed in other values such as stiffness, maximum strain, elastic modulus, and energy density. Therefore, repeated freezing-thawing had histological and biomechanical effect on Achilles tendon in rabbits before allograft tendon transplantation. This indicates that cautions should be taken in the repeated freezing-thawing preparation of allograft tendons in clinical application.
同种异体组织在重建前交叉韧带中的应用越来越多，这使得人们更加关注储存和处理对同种异体移植物的影响。本研究旨在通过在同种异体肌腱移植前对兔跟腱进行反复冻融，观察组织学和生物力学对跟腱的影响。兔跟腱按组织库制造商的方案采集和处理，重复冻融 3 次（第 1 组）和 10 次（第 2 组）。仅接受一个循环的作为对照组。然后，从每组中随机选择肌腱进行组织学观察和生物力学测试。组织学观察显示，随着冻融次数的增加，出现了以下变化：肌腱束和胶原纤维的排列变得紊乱，直至断裂，细胞破裂，肌腱束之间出现明显的间隙，这是由于冰晶的形成。实验组与对照组在最大载荷、最大载荷能和最大应力值方面存在显著差异，而在刚度、最大应变、弹性模量和能量密度等其他值方面无显著差异。因此，同种异体肌腱移植前，反复冻融对兔跟腱具有组织学和生物力学效应。这表明在临床应用中，同种异体肌腱的反复冻融制备应谨慎。
