Wilson Wouter, van Burken Christine, van Donkelaar Corrinus, Buma Pieter, van Rietbergen Bert, Huiskes Rik
Department of Biomedical Engineering, WH 4.118, Eindhoven University of Technology, P.O. Box 513, 5600 MB Eindhoven, The Netherlands.
J Orthop Res. 2006 Feb;24(2):220-8. doi: 10.1002/jor.20027.
Osteoarthritis (OA) is a multifactorial disease, associated with articular cartilage degeneration and eventually joint destruction. The phases of the disease have been described in detail, and mechanical factors play an important role in the initiation of OA, but many questions remain about its etiology. Swelling of cartilage, one of the earliest signs of damage, is proportional to the amount of collagen damage. This strongly suggests that damage to the collagen network is an early event in cartilage degeneration. The goal of this study was to determine the mechanical cause of early collagen damage in articular cartilage after mechanical overloading. Both the shear strain along the fibrils and the maximum fibril strains were evaluated as possible candidates for causing collagen damage. This evaluation was done by comparing the locations of maximum shear and tensile strains with the locations of initial collagen damage after mechanical overloading in bovine explants as found using antibodies directed against denatured type II collagen (Col2-3/4M). Collagen damage could be initiated by excessive shear strains along the collagen fibrils, and by excessive fibrils strains. The locations of collagen damage after mechanical overloading were highly dependent on the cartilage thickness, with thinner cartilage being more susceptible to damage than thicker samples.
骨关节炎（OA）是一种多因素疾病，与关节软骨退变及最终的关节破坏相关。该疾病的各个阶段已被详细描述，机械因素在OA的发病过程中起着重要作用，但其病因仍存在诸多疑问。软骨肿胀是最早的损伤迹象之一，与胶原蛋白损伤量成正比。这强烈表明胶原蛋白网络损伤是软骨退变的早期事件。本研究的目的是确定机械过载后关节软骨中早期胶原蛋白损伤的机械原因。沿纤维的剪切应变和最大纤维应变均被评估为可能导致胶原蛋白损伤的因素。通过比较在牛外植体机械过载后，使用针对变性II型胶原蛋白（Col2-3/4M）的抗体所发现的最大剪切应变和拉伸应变的位置与初始胶原蛋白损伤的位置，来进行这一评估。胶原蛋白损伤可能由沿胶原纤维的过度剪切应变以及过度的纤维应变引发。机械过载后胶原蛋白损伤的位置高度依赖于软骨厚度，较薄的软骨比较厚的样本更容易受到损伤。
