Effect Of Continuous Passive Motion On The Healing Of Full-thickness Defects In Ariticular Cartilage Of Rabbit Knee

Obejectives:The porpose of this study was to analyse the role of varied-time CPM in the repair of full-thickness defects of articular cartilage.Methods:Thirty male New Zealand white rabbits(about three-months -old) ,including sixty knee joints,were divided into three groups averagely:8h/day and intermitttnt active motion (IAM):2h/day and IAM;IAM.In every medial femoral condyle of rabbit knee joint,a 3.2-mm-wide circular full-thickness defect was drilled.At the fourth and twelfth week, half of every group were killed,the sections on the healing of full-thickness defects of osteochondral were researched by immunohistochemical techniques and safranin O staining in order to observe the expression of collagen I and II ,the staining of the glycosaminoglycan portion of cartilage and to know the results of scoring system for gross appearance and histological and histochemical.Results: 1 .The three groups had no significant differences among them in the averge weight and the averge increased weight at the 0,4th ,12th weeks the experiment. (P>0.05) .2.The CPM 8h/day group showed significant difference with the CPM 2h/day group and the IAM group. (P<0.05). However,there was no significant difference between the CPM 2h/day group and the IAM group(P>0.05).3.The positive expression rate of collage I and II of the CPM 8h/day group in the 12th week had a significant difference with the CPM 2h/day group and the IAM group in the 4th week ( P<0.05 ).Conclusions:1.The CPM mechine on rabbit knee joints can be effective to our experiment.But it should be improved in some places .2. The enough period of CPM can have an important influence to the healing of full-thickness defect in articular cartilage:It can improve the rapair of the collge II and glycosaminoglycan of cartilage , the quality and shorten the time of regeneration of full-thickness articular cartilage defects when CPM for 8h/day.But,the CPM for 2h/day and IAM can't have the preceding influence.3.In the same condition,Whether it was cured by CPM at the 4th or 12th week,it has no significant difference in the quality of healing of full-thickness defect in articular cartilage.