Biomechanics Analysis Of Sidestep Cutting Maneuvers In Females Basketball Athletes: Implications For Anterior Cruciate Ligament Injury

Purpose: The purpose of this study was to observe the biological changes of knee joint motion in female basketball players during lateral side cut,and to investigate the kinematics,dynamics and muscle activity of lateral side cut knee joint.In order to understand the causes of ACL injury of female basketball players,it is proposed to provide theoretical basis and guidance for the prevention of sports injury.Methods: Fifteen healthy female collegiate basketball athletes performed sidestep cutting maneuvers,while 6 Vicon Motion System camera and 2 kistler force plate and EMG capture System recorded surface electromyographic data from the medial and lateral hamstrings and quadriceps and 3D motion and ground reaction force data.Lateral and medial quadriceps-to-hamstrings co-contraction,normalized root mean square electromyographic data for medial and lateral quadriceps and hamstrings,knee joint kinematics,and knee moment were calculated and used in data analyses.Findings:Females athletes had a small knee flexion angle,a greater knee abduction and knee internal rotation angle,and a great knee abduction and internal rotation moment during early deceleration.In addition,female athletes displayed less activation in the vastus medialis than in the vastus lateralis and less activation in the medial hamstrings than in the lateral hamstrings.Female athletes had lower co-contraction levels in the medial musculature compared with the lateral musculature.The ratio of lateral Q:H co-contraction had a associations with the knee abduction moment.But at the peak knee abduction angle,female basketball athletes demonstrated peak internal rotation moment.The same as at the small peak knee extension moment,female basketball athletes demonstrated peak knee abduction moment.Conclusions: 1.Female basketball players demonstrated a smaller knee flexion angle,and knee internal rotation,the peak of the valgus angle,the knee early peak moment of stretching during early deceleration,the knee peak moment of valgus and internal rotation external in the coronal and cross plane,the athletes to be at " risk" of ACL injuries.2.In respect of muscle activity,quadriceps femoris is the dominant mode of activity,female athletes displayed great activation in the lateral muscle than in the medial,and ratio of lateral Q:H co-contraction had a associations with the knee abduction moment reduce the stability of joint.3.A knee pronation peak torque at the knee valgus angle of the peak of women's basketball players,knee extension torque appears small peak,a peak valgus moment,ACL continuous stress increases the damage probability.The peak knee abduction angle,female basketball athletes demonstrated peak internal rotation moment,and the small peak knee extension moment,female basketball athletes demonstrated peak knee abduction moment,these can reduce to anterior cruciate ligament continuous stress increases the damage probability.These abnormal movement neuromuscular control strategies,knee move great loads,imbalance neuromuscular control and multi planes joint force association with noncontact Anterior cruciate ligament injures adopted by the female athletes may elucidate the reasons for which female athletes have a more frequently of anterior cruciate ligament(ACL)injures during the early deceleration phase of sidestep cutting task.This may be an important reason for the non contact injury of anterior cruciate ligament in female basketball players.