The Difference Analysis Of Functional Outcome And Drop Vertical Jumping Test Between Patients With Anterior Cruciate Ligament Reconstruction In Different Body Mass Index Classes

Objective:Compare the differences in knee function and drop vertical jumping test between patients in different body mass index(BMI)classes after primary hamstring-graft anterior cruciate ligament(ACL)reconstruction.Materials and Methods:This study was a retrospective study of all patients who were treated with anterior cruciate ligament(ACL)by arthroscopy anterior cruciate ligament reconstruction by same operation between September 2016 and January2018 in our hospital.A total of 27 patients were reviewed,with 24 males and 3females,16 in the left leg and 11 in the right leg,the average patient age was26.59±8.40 years old.Patients were classified into 2 BMI groups:normal-BMI group(BMI<25kg/m~2)and high-BMI group(BMI>25kg/m~2).Compare preoperative and last follow-up's angle of flexion of the affected limbs between the two groups.KT-1000 was used to evaluate knee relaxation,Lysholm score,Tegner score,knee injury and Osteoarthritis Outcome Score(KOOS)to evaluate patients'knee function between preoperative and postoperative.Patients were invited to perform a drop vertical jumping test at the end of two years follow-up after operation to evaluate related knee joint angle change and peak value,torque and reaction force at each stage between two groups.Compare the differences in relevant data between the two groups,analyze postoperative functional rehabilitation and biodynamic differences in drop vertical jumping test between two groups.Results:All 27 patients achieved good clinical efficacy after ACL reconstruction.Except for the angle of flexion,patients'Knee joint relaxation before and after operation in group normal-BMI and high-BMI(7.2±3.7,2.2±1.2;7.0±3.9,2.4±1.5),Lysholm score(61.7±2.4,92.5±8.2;60.1±21.1,89.8±13.2),Tegner score(3.2±1.8,5.7±1.9;2.7±1.8,3.5±1.8),Among the postoperative differences between the two groups,the flexion angle of knee joint(P=0.001,P<0.05)and Tegner score(P=0.007,P<0.05)have significant statistical differences.However,there was no significant statistical difference in the degree of relaxation and Lysholm score of the affected knee(P>0.05).There were no significant differences between the two groups in the KOOS subset score and the two groups in the last follow-up assessment(P=0.39,P=0.862,P=0.101,P=0.945,P=0.688,P>0.05),During the initial contact period of the drop vertical jumping test,There are statistical differences in ground reaction forces at the injured site between normal BMI and high BMI(P=0.005,<0.05).The difference in flexion moment between the two groups was also statistically significant(P=0.039,<0.05),But there was no statistical difference in flexion angle,varus angle and varus moment(P=0.143,P=0.572,P=0.730).In the second stage of the landing,the maximum knee overextension angle(P=0.024,<0.05)produced by the landing was also significantly different.And there was no significant statistical difference in maximum buckling angle,buckling moment,peak extension moment,maximum varus angle,maximum valgus angle,peak valgus moment,and peak valgus torque.While comparing within groups,there was no significant statistical difference in the data of the comparison of the affected limb and the unaffected limb between the patients in both normal BMI and high BMI groups.Conclusion:It is confirmed that ACLR of hamstring single bundle is an efficient treatment option.BMI does not adversely affect the functional results of the affected knee joint.Patients with high BMI have lower ground reaction force,and lower peak flexion moment.Postoperative weight loss is important to protect bilateral knee joints in jump down movement.