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A functional biomechanics garment (FBG) may help to prevent injury by improved kinematics during motion such as single leg drop landing (SLDL). The purpose of this study was to investigate the effects of the FBG on the biomechanics of SLDL. Seventeen female university basketball players participated. Characteristics of the FBG were designed based on biomechanics during weight-loaded performance of human movement. The average values of lower limb kinematics and kinetics in the sagittal and frontal planes from 3 SLDL with and without FBG were measured and compared. The maximum varus angle of the knee showed a significant difference between the use of FBG (15.3 ± 15.1°) and without the use of FBG (5.9 ± 15.4°), the flexion angular displacement of the hip (with FBG, 21.5 ± 8.1°; without FBG, 24.0 ± 6.7°) between with and without FBG. The moment of the hip with FGB (1.1 ± 0.6 Nm) was significantly smaller than without FGB (1.4 ± 0.8 Nm). Regarding function of the FBG, the rigid part of the hip could counter the excessive adduction and flexion of the hip, and the elastic part of the thigh could support the varus moment when the elastic part stretched. Therefore, the subjects with FBG could control the frontal motion of the knee, which has a risk of knee injury, such as the dynamic valgus of the knee during the SLDL. Use of the FBG decreases dynamic knee valgus, which reduces risk of knee injury. • The functional garment may improve sports performance, increase muscular endurance, and enhance recovery. • We have produced a functional biomechanics garment (FBG) based on the biomechanics of braking and inducing joint motion during athletic performance. • We found that the FBG could decrease dynamic knee valgus and adductor moment of the hip. • Our functional garment can decrease dynamic knee valgus during the single leg drop landing, which may prevent knee injuries, such as ACL injury, which is related to dynamic knee valgus. [ABSTRACT FROM AUTHOR]

Study aim: to examine the differences in landing kinetics factors (LKF) to assess the whole body stability and preparatory muscle activation (PMA) in female handball players with and without dynamic knee valgus.

Background: ‪Biomechanical factors are the main mechanism of load applied on the anterior cruciate ligament (ACL). The aim of this study was to evaluate the effect of eight weeks of core stability training on the lower extremity joints moment during a single leg drop landing task. Material and methods: ‪Thirty basketball athletes were randomly assigned into training and control groups. The training group performed core stability training for 8 weeks, but the control group did not perform these exercises. Lower extremity kinetics and kinematics variables during a single leg drop landing test were collected by a motion analysis system and a force plate in a pre- and post-test. Data were analyzed using a mixed repeated measure ANOVA test (p ≤ 0.05). Results: ‪The results showed there was a significant reduction in the moment of flexion, adduction and rotation of the hip and the moment of the knee and subtalar joint in the training group (p < 0.05), while there was no significant reduction in the ankle moment (p > 0.05). Conclusions: ‪Core stability training that was used in this study can reduce the forces exerted on the lower extremity joints during single leg drop landing. So, this study provides evidence that core stability training reduces lower extremity joints moment and may reduce the risk of ACL injury in athletes.

Background and Objective: Genuvarum is considered as one of the risk factors for the incidence of osteoarthritis. This study was done to compare the knee joint muscles activity during single leg drop landing from different heights among men with genu varum and men with normal knee. Methods: This case – control study was done on 20 male students with genu varum deformity and 20 male students with normal knee. Genu varum deformity was measured by a kolis and goniometer. Muscle activity of lower limb was recorded with electromyography. Results: There was significant difference in muscles activity of medialis gastrucnemius, peroneus longus, biceps femoris and gluteus medius in cases and controls (P

Objective: pesplanus is one of the changes that brings about changes in muscle activation patterns. Being aware of muscles activity changes in various standing positions among pesplanus patients provides insights into preventing lower extremity injuries in this population. The aim of this study was to compare leg muscles electromyography during various standing positions in pesplanus and normal subjects. Methods: 60 healthy male university students, 30 subjects with pesplanus deformity (with average age 23/54±3/57 year, average height 175/34±7/62 cm, average weight 74/87±10/72 kg ) and 30 normal subjects (with average age 22/97±2/38 year, average height 176/6±5/59 cm, average weight 73/58±8/36 kg ) participated in this comparative study. Deformity of pesplanus was assessed with navicular drop test. Each subject performed single-leg landing dropping from 30cm height onto a force platform where muscles activity was recorded with EMG device. For data analysis, Matlab and Spss softwares were used and independent sample t-test was used to compare the dependent variables at a significance level of P &le 0/05. Results: Significant differences were observed between the two groups for the activities of the longus peroneus and anterior tibialis muscles ( p&le0/05) while no significant differences were observed in other muscles. Conclusion: The changes in the normal structure of the foot might affect muscle activities during standing, which can cause changes in the injury patterns. Therefore, it is proposed that focusing on corrective exercises and therapy plan can reduce these risks.

Background: Biomechanical factors are the main mechanism of load applied on the anterior cruciate ligament (ACL). The aim of this study was to evaluate the effect of eight weeks of core stability training on the lower extremity joints moment during a single leg drop landing task. Material and methods: Thirty basketball athletes were randomly assigned into training and control groups. The training group performed core stability training for 8 weeks, but the control group did not perform these exercises. Lower extremity kinetics and kinematics variables during a single leg drop landing test were collected by a motion analysis system and a force plate in a pre- and post-test. Data were analyzed using a mixed repeated measure ANOVA test (p ≤ 0.05). Results: The results showed there was a significant reduction in the moment of flexion, adduction and rotation of the hip and the moment of the knee and subtalar joint in the training group (p < 0.05), while there was no significant reduction in the ankle moment (p > 0.05). Conclusions: Core stability training that was used in this study can reduce the forces exerted on the lower extremity joints during single leg drop landing. So, this study provides evidence that core stability training reduces lower extremity joints moment and may reduce the risk of ACL injury in athletes. [ABSTRACT FROM AUTHOR]

Purpose: The purpose of this study was to investigate the kinematic and kinetic variables, which predict anterior tibia shear force during single-leg landing in female athletes. Methods: Forty-three subjects (mean and standard deviation for age 21.12 ± 2.00 y, height 168.58 ± 7.62 cm, and weight 60.27 ± 7.80 kg) participated in this study. Kinematic and kinetic variables of lower extremity and trunk during single-leg landing were collected by 5 Vicon cameras and Kistler force plate. Stepwise multiple regression and Pearson correlation were used to identify predictor variables of anterior shear force (P ≤ 0.05). Results: Peak of extensor moment (P = 0.004, r = -0.394) and maximum knee flexion (P = 0.007, r = -0.370) were the best predictors that explained 30% of the variance of the shear force data. Therefore, rise in maximum extensors moment of knee and knee maximum flexion causes increase and decrease in anterior shear force, respectively. In addition, a significant relationship between trunk flexion (P = 0.039) and knee flexion angular velocity (P = 0.048) at the moment of initial contact with the anterior shear force. Conclusion: On the basis of previous research, and the relationship between clinical findings, the noncontact of anterior cruciate ligament injury during landing was confirmed. These results can be used in prospective studies examining modifiable noncontact risk factors of ACL injury.

Background and Objective: Genuvarum is considered as one of the risk factors for the incidence of osteoarthritis. This study was done to compare the knee joint muscles activity during single leg drop landing from different heights among men with genu varum and men with normal knee. Methods: This case - control study was done on 20 male students with genu varum deformity and 20 male students with normal knee. Genu varum deformity was measured by a kolis and goniometer. Muscle activity of lower limb was recorded with electromyography. Results: There was significant difference in muscles activity of medialis gastrucnemius, peroneus longus, biceps femoris and gluteus medius in cases and controls (P<0.05), while no significant difference was observed in other muscles. Conclusion: The changes in the knee normal structure might affect daily activities and possibly lead to in injuries due to physical training. [ABSTRACT FROM AUTHOR]

[Purpose] The purpose of this study was to examine the influence of static knee alignment on knee-in and tibial rotation, and the relationship between knee-in and tibial rotation angle during a single leg drop landing. [Subjects] One hundred three women were classified into 3 groups: valgus (7), neutral (10) and varus (10) based on static alignment of their knees. [Method] Three-dimensional motion analysis was carried out during a single leg drop landing from a platform 30 cm in height. [Results] The variation of knee-in angle in the the varus group was significantly greater than that in the valgus group. The tibia was internally rotated in the valgus group and externally rotated in the varus group. There was a correlation between the variation of knee-in angle and the variation of the tibial rotation angle. [Conclusion] The direction of tibial rotation was influenced by static knee alignment, and the variation of knee-in angle was influenced by the direction of the tibial rotation. [ABSTRACT FROM AUTHOR]