Animal Experimental Study To Static Force Structure Of Stiffknee

【Objective】: Establish knee stiffness models of rabbit through the ways of internal fixation or external fixation . study the histological and biostatical changes of the static force structure in rabbit stiffknee models, compare the factors that form stiffknee in many ways. Study the significance in forming knee stiffness models that the histological and biostatical changes of the static force structure play .study the feasibility and dependability of the experiments of establishing knee stiffness models . research the biomechanical, anatomical and histological changes of the static force structure in the stiffknee Established by 4 ways, research the rehabilitative Methods to the knee after internal fixation or external fixation.【Methods】:1. Establish knee stiffness models of rabbit through the ways of internal fixation or external fixation:choose 40 mature new_zealand rabbits,the rabbts were divide into 5 groups at random, group A1,groupA2 ,groupB1 ,groupB2 and groupC, 8 rabbits per group,the right knee of the rabbits in groupA was fixed through plaster external fixation,groud A1 fixed 6 weeks,groud A2 fixed 12 weeks; the right knee of the rabbits in groupB was fixed through inter medullary fixation with Kirschner wire ,groupB1 fixed 6 weeks, groupB2 fixed 12 weeks,groupC was control group, the knees were not fixed. 2.when got to the time we expected, we dissect every knee of all the rabbits, compare the shape of every knees, measure the length and cross section area of medial collateral ligaments, lateral collateral ligaments ,anterior cruciate ligaments ,posterior cruciate ligaments of every knees, and study the historical change in them through pathological section. Measure biostatical changes of anterior cruciate ligaments of right knee in every group.【Results】: 1.The right knee in group A1.A2.B1.B2 are all become stiff, there was no obvious significance by the statistics compare on ROM in group A1.A2.B1.B2. (P<0.01) and have obvious significance by the statistics compare to groupC. there was no obvious significance by the statistics compare on lenth of the MCL LCL ACL in groupA1.A2.B1.B2.C. there was no obvious significance by the statistics compare on cross section area of the MCL LCL ACL PCL in group A1.A2.B1.B2. and have obvious significance by the statistics compare to groupC. (P<0.01) there was no obvious significance by the statistics compare on biostatics of the MCL LCL ACL PCL in group A1.A2.B1.B2. and have obvious significance by the statistics compare to groupC. (P<0.01)【Conclusion】: the way fix knee through inter medullary fixation with Kirschner wire can Establish rabbit stiffknee models well,the changes of static force structure of stiffknee the most important factor which induce stiffknee; the pathological change of the static force structure happens mainly in the early and intermediate stage that form stiffknee,and not obviously in later stage.