骨性关节炎动物模型外侧副韧带的拉伸力学性质

背景：了解骨性关节炎时膝关节外侧副韧带的拉伸力学性质，对预防和治疗骨性关节炎非常有必要，但这方面的报道不多。目的：建立骨性关节炎动物模型，比较正常和骨性关节炎动物膝关节外侧副韧带的拉伸力学性能指标，提出骨性关节炎对外侧副韧带拉伸力学性质影响的定性定量化参考数值。设计、时间及地点：随机对照实验，于2008-11-20/30在吉林大学力学实验中心完成。材料：6月龄雄性SD大鼠20只，随机分成正常对照10只，模型组10只。方法：模型组大鼠复制骨性关节炎模型。在日本岛津电子万能试验机上对正常和病态组各10个试样进行拉伸实验。拉伸实验的速度为5 mm/min。以多项式用最小二乘法处理实验数据。主要观察指标：拉伸最大载荷、最大位移、最大应力、最大应变、应力-应变曲线。结果：正常对照组最大载荷为(12.754±2.795) N，最大应力为(27.681±5.832) MPa，最大位移为(2.754±0.707) mm，最大应变为(11.679±2.373)%；模型组最大载荷为(7.183±1.817) N，最大应力为(16.162±3.403) MPa，最大位移为(1.827± 0.768) mm，最大应变为(8.019±2.811)%。正常对照组各项拉伸性能指标显著大于模型组(P < 0.05)。结论：骨性关节炎时，可以使膝关节拉伸最大载荷、最大位移、最大应力、最大应变降低、对膝关节外侧副韧带拉伸力学性能及应力松弛性具有一定影响。

Tensile mechanical properties of lateral collateral ligaments in animal models of osteoarthritis

BACKGROUND: It is very necessary for the prevention and treatment of osteoarthritis (OA) to understand the tensile mechanical properties of lateral collateral ligaments (LCLs) of knee joints with osteoarthritis, while reports on it are still few.OBJECTIVE: To compare the LCL tensile mechanical property indexes of knee joints between normal animals and OA models established for this purpose, and to provide qualitative and quantitative referential data about effects of OA on the LCL tensile mechanical properties of animal knee joints.DESIGN, TIME AND SETTING: A randomized controlled trial was finished at the Mechanical Experimental Center of Jilin University from December 20th to 30th in 2008.MATERIALS: A total of 20 male SD rats of 6 months old were divided into a normal control group and a model group, with 10 ones in each group.METHODS: Rats in the model group were copied into OA models, after which test on tensile was performed to each of the ten rats in the two groups at the speed of 5 mm/min on Universal Testing Machine, Shimadzu. Data obtained from the test were processed in polynomial though least square method.MAIN OUTCOME MEASURES: Tensile maximum load, maximum displacement, maximum stress, maximum strain and stress-strain curves.RESULTS: The tensile maximum load, maximum stress, maximum displacement and maximum strain in the normal control group and the model group were (12.754±2.795) N, (27.681±5.832) MPa, (2.754±0.707) mm, (11.679±2.373)% and (7.183±1.817) N, (16.162±3.403) MPa, (1.827±0.768) mm, (8.019±2.811)% respectively, from which we could see that each index in the normal control group was greater than that in the model group obviously (P < 0.05).CONCLUSION: The tensile maximum load, maximum stress, maximum displacement and maximum strain all decreased after OA, which indicates that osteoarthritis has certain effects on tensile mechanical properties of LCLs of knee joints as well as stress relaxation.