| Objective: Ankle sprain is one of common injuries in sports,while cutting movement is one of the risk factors which could contribute to ankle sprain.Besides,females have higher risks to suffer from ACL injury in cutting maneuvers than males.Wearing ankle brace can reduce the angle of ankle inversion which has been proved as an effective method to reduce the risks of ankle sprain.However,few researches have investigated the effects of wearing ankle braces on the kinematics and kinetics of the lower limb joints during cutting maneuvers.Therefore,the purpose of this study is to explore the kinematics and kinetics characteristics of lower limbs in females to wear different ankle braces when adopting different cutting methods.Methods: Twenty females were volunteered to attend the study(mean age 24.1 ±2.1 years,height 159.4 ± 6.3cm,weight 53.2 ± 5.2kg).The subjects were required to complete side-step cutting and cross-step cutting at the speed of 4m/s under the three different conditions(no brace,hinged ankle brace(Active T2)and lace up ankle brace(ASO)).Vicon infrared motion capture system of 8-cameras were used to collect the kinematic data during different cutting maneuvers.The sampling frequency was set as 200 Hz.A three-dimensional force platform was used to measure the 3D ground reaction force,and the sampling frequency was set as 2000 Hz.VICON Nexus and Visual 3D software were used to process and obtain 3D joint angle,3D angular velocity and 3D joint moment of the hip,knee and ankle joints during cutting,as well as the ground reaction force of the anterior-posterior direction,medial-lateral direction and vertical direction.All data were expressed as mean ± SD,and SPSS 22.0statistical software was used for statistical analysis.Two-way analysis of variance with repeated measures was used to compare the differences in lower limb kinematic and kinetic parameters between different braces and different cutting maneuvers,the significance level was set to p<0.05.Results:1.Kinematics:The hip joint kinematics will not be changed when wearing hinged or lace-up ankle brace performing side-step cutting or cross-step cutting(p>0.05).When performing side-step cutting,both lace-up and hinged ankle barce can significantly increase the peak angle of knee internal rotation(p < 0.05),and significantly reduced the peak angle of ankle inversion(p < 0.05),and the hinged ankle barce limits the peak angle of ankle inversion more obviously.In addition,the lace-up ankle barce can significantly reduce the peak angle of ankle plantar-flexion and the angle of ankle internal rotation when the foot contacts the ground(p<0.05),while the hinged ankle barce has effects to significant increase the peak angle of knee valgus(p<0.05).when performing cross-step cutting,both hinged and lace-up ankle barce could reduce the knee flexion angle when the foot contacts the ground(p < 0.05).In addition,lace-up ankle barce can significantly reduce the peak ankle plantar-flexion Angle(p<0.05),and hinged ankle barce has effects to significant reduce the angle of ankle valgus when the foot contacts the ground(p<0.05).When performing side-step cutting under the condition of no-brace,hinged and lace-up ankle brace,compared with cross-step cutting,knee flexion(p<0.05),valgus(p<0.05),external rotation(p<0.05)and hip extension(p<0.05)peak angles are higher,while the peak angle of knee internal rotation is lower(p<0.05).Throughout the support period,the side-step cutting is dominated by hip abduction and ankle inversion,the cross-step cutting is dominated by hip adduction and ankle eversion.2.Kinetics:The hip joint kinetics will not be changed when wearing hinged or lace-up ankle brace performing side-step cutting or cross-step cutting(p>0.05).When performing side-step cutting,the ankle valgus moment of the hinged brace is significantly higher than that of the no-brace and the lace-up brace(p<0.05).When performing cross-step cutting,the knee internal rotation of the hinged brace is significantly higher than that of the no-brace(p<0.05).When performing side-step cutting under the condition of no-brace,hinged and lace-up ankle brace,compared with cross-step cutting,ankle plantar-flexion(p<0.05),eversion(p<0.05),internal rotation peak moment(p<0.05),knee valgus(p<0.05),external rotation peak moment(p < 0.05),and hip abduction(p < 0.05),internal rotation(p < 0.05)peak moment are higher,ankle inversion(p < 0.05),external rotation peak moment(p<0.05),and knee varus(p<0.05),internal rotation(p<0.05)peak moment are lower.When performing side-step cutting under the condition of no-brace,hinged and lace-up ankle brace,compared with cross-step cutting,the peak forward(p<0.05),inward(p<0.05),vertical(p<0.05)ground reaction force and the average,maximum loading rate(p < 0.05)are higher,but the peak outward ground reaction force is smaller(p<0.05).Conclusion:1.When performing side-step cutting under the conditons of hinged and lace-up ankle brace,which can reduce the ankle inversion angle and increase the knee internal rotation angle.Among them,wearing hinged ankle brace can also increase the angle of knee valgus.Therefore,wearing ankle brace during the side-step cutting can effectively prevent ankle sprains.However,wearing hinged and lace-up ankle brace may increase the risk of anterior cruciate ligament(ACL)injury in females during side-step cutting,and the risk of anterior cruciate ligament(ACL)is higher when wearing hinged ankle brace.When performing cross-step cutting under the conditons of hinged and lace-up ankle brace,the knee internal rotation moment are increased.Therefore,it is possible to increase the risk of injury of the medial collateral ligament(MCL)of the lower limbs in females with hinged and lace-up ankle braces during cross-step cutting.The hip joint kinematics and Kinetics will not be changed when wearing hinged or lace-up ankle brace performing side-step cutting or cross-step cutting.2.Comparing different cutting maneuvers:when performing the side-step cutting,the ankle inversion,knee valgus and external rotation load are higher,and the lower limbs absorb higher vertical and inward ground reaction force and higher vertical loading rates.When performing cross-step cutting,the knee varus and internal rotation load are higher.Therefore,the risk of ankle sprain,anterior cruciate ligament(ACL)injury and the stress fracture of lower limbs are higher during side-step cutting.The risk of medial and lateral collateral ligament(MCL,LCL)injuries are higher during cross-step cutting. |
PDF Full Text Request