Long-term Clinical Effect And Kinematic Analysis Of Cruciate Ligament Reconstruction With LARS Artificial Ligament

BackgroundKnee cruciate ligament injury is a common sports injury,arthroscopic cruciate ligament reconstruction is the most effective treatment.LARS artificial ligament is a new generation of artificial ligament graft,which has been widely used in knee cruciate ligament reconstruction all over the world in the past decade.At present,the long-term clinical effect of cruciate ligament reconstruction with LARS artificial ligament is still controversial,and the current clinical trials lack the analysis of knee joint stability and kinematics in long-term postoperative patients.ObjectivesPart Ⅰ : To evaluate the long-term clinical effect of knee cruciate ligament reconstruction with LARS artificial ligament.To explore the influencing factors of longterm clinical effect.PartⅡ: To compare the static knee laxity and six degrees of freedom of level walking between patients after knee cruciate ligament reconstruction with LARS artificial ligament and healthy adults.To evaluate patients’ knee kinematic function in the long term after operation.MethodsPartⅠ: From 2005 to 2014,a total of 153 patients who underwent knee cruciate ligament reconstruction with LARS artificial ligament were enrolled and divided into ACL reconstruction group,PCL reconstruction group,and combined ACL+PCL reconstruction group according to the type of injury and reconstructed ligament.On the basis of general patient information collected through the electronic medical record system,all patients received the last follow-up between March and September 2022.Pre-and post-injury Tegner scores and pre-and post-operative Lysholm scores were collected at the last follow-up.The postoperative Lysholm score and postoperative Tegner score were used to evaluate the overall function and motion level of the patients’ knee joints.The influencing factors of longterm clinical effect after operation were explored by multiple linear regression analysis and correlation analysis between variables.PartⅡ: On the basis of the first part of the study,35 long-term postoperative patients and 15 healthy adults were enrolled.The static stability of knee joint was evaluated by measuring the side-to-side difference in tibial translation under 150 N stress by Ligs joint ligament digital physical examination instrument.The 6DOF spatial data of knee joint were collected by Opti Knee digital navigation joint three-dimensional dynamic evaluation system and compared with the healthy control group.ResultsPartⅠ: A total of 153 patients who underwent knee cruciate ligament reconstruction with LARS artificial ligament between 2005 and 2014 at our study institution that fulfilled the nappy criteria were enrolled in this part of the study,including 107 patients in the ACL reconstruction group,34 patients in the PCL reconstruction group,and 12 patients in the combined ACL+PCL reconstruction group.In all three groups,the mean Lysholm scores at the last follow-up were better than preoperative(P<0.001),and the mean Tegner scores at the last follow-up were lower than pre-injury(P<0.001).Multiple linear regression analysis was performed with age,gender,follow-up time,time from injury to operation,preoperative Tegner score,and preoperative Lysholm score as independent variables and postoperative Tegner score as dependent variable.The results showed that the regression model was statistically significant(P<0.001)and that the independent variables explained 65.8% of the variance in postoperative Tegner score.Significance tests showed a statistically significant effect of age(B=-0.027,β=-0.274,P<0.001),follow-up time(B=-0.006,β=-0.166,P=0.001),and preoperative Tegner score(B=-0.562,β=0.577,P < 0.001)on postoperative Tegner score.The effects of gender and BMI of patients,time from injury to operation,and preoperative Lysholm score on postoperative Tegner score were not statistically significant(P > 0.05).Multiple linear regression analysis of postoperative Lysholm scores by the same method showed that the regression model was statistically significant(P<0.001)and that the independent variables explained 40.6% of the variance in postoperative Lysholm scores.Significance tests showed that age(B =-0.389,β =-0.551,P < 0.001),follow-up time(B =-0.035,β =-0.138,P = 0.038),time from injury to operation(B =-0.019,β =-0.188,P =0.011),and preoperative Lysholm score(B = 0.135,β = 0.259,P = 0.001)had a statistically significant effect on the postoperative Lysholm score.The effects of patient gender,BMI,and preoperative Tegner score on postoperative Lysholm score were not statistically significant(P > 0.05).PartⅡ: A total of 35 patients who underwent knee cruciate ligament reconstruction with LARS artificial ligament were enrolled in this part of the study,including 15 patients in the ACL reconstruction group,12 patients in the PCL reconstruction group,and 8 patients in the combined ACL+PCL reconstruction group.Another healthy control group was set up with15 cases.Under the condition of knee flexion 20～30 degrees and 150 N stress,the mean ATTSSD in ACL reconstruction group was(2.53 ±3.02)mm,the mean PTT-SSD in PCL reconstruction group was(2.83 ±3.58)mm,the mean ATT-SSD in combined ACL+PCL reconstruction group was(2.83 ±2.99)mm,the mean PTT-SSD in combined ACL+PCL reconstruction group was(3.35 ±2.18)mm.The mean values of knee varus and valgus,internal and external rotation,flexion and extension,anterior and posterior displacement,up and down displacement mobility in the healthy control group were not significantly different from the three groups of patients(P > 0.05).The mobility of internal and external displacement of the knee joint in the healthy control group was less than that in the PCL reconstruction group and the combined ACL+PCL reconstruction group,and the difference was statistically significant(P=0.046).Conclusion1.The long-term clinical effect after the reconstruction of cruciate ligament with LARS artificial ligament was satisfactory.Advanced age and delayed reconstruction were risk factors for poorer postoperative outcomes,and patients’ knee function tended to decline with increasing postoperative follow-up.2.The patients who underwent the reconstruction of cruciate ligament with LARS artificial ligament show satisfied stability of knee joint,and their walking gait on flat ground is similar to that of a normal person.