Tensile mechanical properties of lateral collateral ligaments in animal models of osteoarthritis / 中国组织工程研究

ABSTRACT

BACKGROUND:It is very nscessary for the prevention and treatment of ostaoarthritis(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 medels 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.DESlGN,TIME AND SETTING:A randomized controlled trial was finished at the Mechanical Expedmental Center of Jilin University from December 20th to 30th in 2008.MATERIALSA total of 20 male SD rats of 6 months old were divided into a normal control group and a model group,with 10ones in each group.METHOOSRats 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 5mm/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.