Analysis Between Running Posture And Muscle Strength Of Knee Pain Runners

Purpose:The muscle strength of the main muscle group of the lower extremities were analyzed.The kinematics and dynamics of lower limbs during jogging were compared.The high risk factors of knee pain were analyzed,and the prediction method of muscle strength or running gait test for knee pain was established.Methods:In 'this study,100 runners from Nanjing were recruited through the Internet,and the incidence of knee pain were investigated by using standard knee pain questionnaire and running habit questionnaire.The muscle strength of the lower extremity is tested by BTERS,kinematics and dynamics during jogging are tested by Vicon.Result:1.84%runners have been or are suffering from running injuries,with 79%for women and 87%for men.The highest percentage of running injuries is knee injuries,46%for men and 43%for women.2.The difference between female knee pain group and non-knee pain group in the eccentric strength of gluteus muscle(P<0.05),internal rotation angle of left hip joint(P<0.01),internal and external rotation angle of right hip joint(P<0.01),right leg knee joint adduction,abduction angle(P<0.01),right knee joint internal rotation.The external rotation angle(P<0.05,)the flexion moment of left hip joint(P<0.05),the adductive moment of right hip joint(P<0.05),the peak value of extension moment of left knee joint(P<0.05),the peak value of right ankle flexion moment(P<0.05).3.There were significant differences in the H/Q ratio(P<0.05),the left knee flexion torque(P<0.05),and the peak value of the right knee' s posterior force(P<0.05)in the male knee pain group and the non knee pain group.4.The risk factors of knee pain in female runners were as follows:the peak value of external rotation of right hip joint<7.66,the peak value of extension angle of right hip joint>6.97,the peak value of external rotation moment of right hip joint>0.03,and the risk factor of knee pain of male runner was:the peak value of left ankle joint dorsal flexion moment<.0.12,and the left knee joint closure.The peak value of abduction>-3.15,the peak value of backward force of right knee joint<0.1,the muscle strength of left leg popliteal muscle less than 68 of quadriceps femoris muscle,and the peak value of external rotation of left hip joint<14.59.Conclusion:1.The incidence of pain in Chinese runners is as high as 84%,among which knee pain is the highest,about 45 percent of all injury types.2.The muscle strength of abductor muscle group in female knee pain group was weaker than that in non-knee pain group.There is a more pronounced hip rotation during running.Female knee pain runners may cause abnormal pressure between the tibial plateau because of the excessive extension of the knee joint in the course of running.In the female knee pain group,the deficiency of the tibiofemoral joint during running may lead to the decline of the stability of the knee joint.In the female knee pain group,the flexural torque of the left hip joint was significantly higher than that of the non-knee pain group,and the extension torque of the left knee joint was lower than that of the non-knee pain group,and that of the right ankle joint was greater than that of the right ankle joint.3.The male knee pain runners showed higher H/Q ratio than the non-knee pain runners.In the knee pain group,the flexural moment of the left knee joint and the backward force of the right knee joint were significantly lower than those of the non-knee pain group.