Clinical Evaluation Of The Graft Initial Tension In ACL Reconstruction With BPTB

Objectives ACL injury is the most common cause of sports injury and it is necessary for injuried joint to be treated.ACL reconstruction with arthrocope has been prevalent.With more understanding to arthrocope technology,initian tension,given when the tibial bone-plug is fixed, is becoming more and more important.The goal of this study is to evaluate the influence of initian tension in ACL reconstruction with BPTB,and according to the result of the study,the optimal graft initial tension will be achieved.Methods Forty-five consecutive patients who had undergone ACL reconstruction with BPTB during September 2005 to December 2006 were evaluated respectively at pre-operation,post-opeation 3 months,post-opeation 6 months,post-opeation 9 months with the mean follow-up of 9 months(range from 3-14 months).patients were randomly divided into three groups,the first group was given 20N initian tension,The second group was given 40N initian tension,the other group was given 60N initian tension.The criteria of functional evaluation we used during follow-up were based on IKDC scoring system and Lysholm-Gilquist scoring system.At pre-operation,post-opeation 3 months,post-opeation 6 months,post-opeation 9 months,the outcomes were observed and compared.Results IKDC Score:Before operation,none was graded A and B in 20N group,six cases were graded C in 20N group,nine cases were graded D in 20N group;none was graded A and B in 40N group,five cases were graded C in 40N group,ten cases were graded D in 40N group, none was graded A and B in 60N group,five cases were graded C in 60N group,ten cases were graded D in 60N group.Statistic analysis show Hc=0.19,P＞0.05,the significance was not achieved among 3 groups.At 3 months after operation,none was graded A in 20N group,six cases were graded B in 20N group,five cases were graded C in 20N group,four was graded D in 20N group;none was graded A in 40N group,seven cases were graded B in 40N group,six cases were graded C in 40N group,two was graded D in 40N group;none was graded A in 60N group,six cases were graded B in 60N group,seven cases were graded C in 60N group,two was graded D in 60N group.Statistic analysis show Hc=0.45,P＞0.05,the significance was not achieved among 3 groups.At 6 months after operation,none was graded A in 20N group,eight cases were graded B in 20N group,three cases were graded C in 20N group,one was graded D in 20N group;none was graded A in 40N group,nine cases were graded B in 40N group,two cases were graded C in 40N group,one was graded D in 40N group;none was graded A in 60N group,eight cases were graded B in 60N group,two cases were graded C in 60N group,two was graded D in 60N group.Statistic analysis show Hc=0.29,P＞0.05,the significance was not achieved among 3 groups.At 9 months after operation,none were graded A in 20N group,three cases were graded B in 20N group,four case was graded C in 20N group,none was graded D in 20N group;two were graded A in 40N group,five case was graded B in 40N group,none case was graded C in 40N group,none was graded D in 40N group;none was graded A in 60N group,four cases were graded B in 60N group,three cases were graded C in 60N group,none was graded D in 60N group.Statistic analysis show Hc=7.32,P＜0.05,the significance was achieved among 3 groups.Lysholm-Gilquist score:The average score of 20N group was 63.5±4.2 before operation.The average score of 40N group was 62.3±4.9 before operation.The average score of 60N group was 61.1±4.4.Statistic analysis show F=1.046,P＞0.05,the significance was not achieved among 3 groups.There was no significance among 3 groups before operation.At 3 months after operation,the average score of 20N group was 68.7±5.3,the average score of 40N group was 68.3±4.9,the average score of 60N group was 66.9±5.5..Statistic analysis show F=0.47,P＞0.05,the significance was not achieved among 3 groups.At 6 months after operation, the average score of 20N group was76.7±2.9,the average score of 40N group was 77.0±3.3,the average score of 60N group was 76.4±3.6.Statistic analysis show F=0.096,P＞0.05,the significance was not achieved among 3 groups.At 9 months after operation,the average score of 20N group was 83.6±2.7,the average score of 40N group was 86.6±3.2,the average score of 60N group was 80.3±2.8.Statistic analysis show F=8.46,P＜0.05,the significance was achieved among 3 groups.Conclusions An optimal initial tension should be applied to the autograft when the bone plug is fixed firmly by the insertion of a mini screw,It is benifical to the function recovery of patients.The result of experiment show 40N initial tension is optimal.