Study On Chronic Low Back Pain Of Sanda Athletes

Objective:In this research Sanda athletes are employed as the research objects. According tothe characteristics of the special training and epidemiological investigation, this studyis to analyze the waist muscle control and coordination mechanism of Sanda athleteswith the chronic low back pain（CLBP）, the muscle strength, proprioceptions, etc. bymuscle electrophysiology, muscle form, biomechanics research methods, to explorethe relevant circumstance of waist muscle force in the process of the round kicks byusing Anybody to model simulation software, investigate the CLBP characteristicsand mechanism of Sanda athletes so as to provide the reference of treatment,rehabilitation and the training after injury and further research related to the athleteswith CLBP.Methods:The132athletes of4male professional Sanda teams from Shanghai, Zhejiang,Guangdong, Henan provinces and two male professional Sanda classes of grade2-3inShanghai Sports university have been surveyed by using the self-designed back painquestionnaire (Reliability and validity meet the requirement.)15Sanda athletes are chosen as the research objects. Among them, CLBP group—arranged as experimental group (8Sanda athletes with CLBP) and NLBP group—as control group (7normal Sanda athletes without low back pain). These2groupsreceive EMG test about the lower back muscle of different actions, waist mobility testof the different actions, waist muscle test, lumbar proprioception test and musclemorphology measurements respectively to analyze function characteristics of Sandaathletes with CLBP.According to a Sanda athletes’ height, weight, thigh length, leg length and othermeasurement parameters，building human musculoskeletal model With Anybodysoftware system. Get its whip leg movements in the process of kinematics anddynamics of C3d data to drive the body musculoskeletal model.Results:（1） As epidemiological survey,50.0%of Sanda athletes are liable to suffer fromLBP, among them14.4%was CLBP. The technological movements causing the waistinjury, throwing techniques account for31.6%, leg techniques,42.1%. （2） Using surface electromyography to evaluate of back muscle feedforwardactivity, activation timing and degree of activation, the result is that CLBP group andNLBP group have significant differences between groups (P <0.05) in three muscles(opposite multifidus, ipsilateral external oblique and ipsilateral internal oblique). Andmuscle activation time of NLBP group is earlier than experimental group. NLBPgroup can use feedforward activity way to activate7muscles, that is, bilateral verticalspinal muscular, crack, internal oblique muscle and so on. While NLBP group onlyactivates3muscles, namely, vertical spinal muscular, side more muscle to crack andthe internal oblique muscle.The left side kick, the activation order of CLBP group’ trunk muscle is thecontralateral erector spinae firstly then the activation of the external oblique muscle,while NLBP group was first activated muscle ipsilateral abdominal oblique andcontralateral multifidus muscle. Activation of dorsal muscles of the trunk of the CLBPgroup slightly higher than the painless group, there is no difference statistically.When the Right leg whip, the CLBP group’ trunk muscle activation sequence isthat first activate contralateral abdominal oblique and erector spinae, and NLBP groupwas first activated muscle is the contralateral abdominal oblique muscle and theipsilatera lmultifidus muscle. RMS value of the ipsilateral erector spinaes groups aresignificant difference (P <0.05), the RMS value of the CLBP group is more large.（3）Using of the Contrex isokinetic dynamometer to test back muscle strength,endurance and proprioception sensory function, the result is that in60°/s,90°/s,120°/s three different angular velocity, CLBP group’ Athletes in flexion andextension muscle peak torque values are less than the value of the NLBP group (P>0.05). The extensor average power values of CLBP group less than the painless group(P>0.05)。In CLBP group， there were significant differences (P <0.05) betweenflexor and extensor value of the average power，There were significant differences (P<0.05) between60°/s and120°/s. Comparison of trunk muscle endurance, CLBPgroup of peak torque decline rates were20.8%,23.3%less than27.8%of NLBPgroup’s and29%.Using proprioception test, CLBP group’ reposition error value is greater than theNLBP group at15°(P <0.05) and30°angle (P>0.05).（4）Using of MRI technology to test the morphological changes of the lumbarmuscles, the result is that one athlete of CLBP group (xx)，the cross sectional area ofPsoas muscle was significantly greater than the NLBP group, and muscle fiberbundles, multifidus, erector spinae is more difficult to be distinguished.（5）Using Vicon kinematic technology to test the waist activity, the result is thatwhen the left side kick or Right leg whip, the range of trunk action of the CLBP groupin Y, Z-axis is relatively large. （6）Building AnyBody body modeling and simulation system model of Sandaathletes right leg whip action. The degree of muscle activation obtained show that thestage of the whip leg whipping, the activation of the left erector spinae is much higherthan the right, whereas the left multifidus, is indeed significantly lower degree ofactivation of the left abdominal obliqueon the right.Conclusions:（1）The prevalence rate of CLBP of Sanda athletes is relatively high, and thetechnical movements to injury waist is mainly wrestling and leg.（2） The trunk muscle electrical activity of Sanda athletes with CLBP exists tocontrol abnormal activation delay, while the decreased proprioception. Side kick andwhip leg movements, Sanda athletes with CLBP has back muscle activation time,activation of the abnormal, suggesting that the group of athletes waist musclecoordination and control drop.（3）The trunk muscle strength of Sanda athletes with CLBP is low, extensorexplosiveness low. Morphological studies have shown that Sanda athletes with CLBPwaist muscles such as erector spinae, multifidus muscle tissue morphologydegenerative disorders, suggesting that the symptoms of Sanda athletes with CLBPhave related to the muscle strength decreased and lumbar structural degeneration.（4）Throughout the course of action of the side kick and whip legs, the waistactivities change rate of Sanda athletes with CLBP is relatively large, suggesting thatSanda athletes with CLBP weaken the control of posture.（5）Using theAnyBody human modeling and simulation system build the simulationmodel of skeletal muscle about right leg whip action of Sanda athletes, with a certainreference value to study the muscle force.