不同膝关节角度时股四头肌的电机械应答规律

发布时间：2018-05-21 06:25

本文选题：膝关节角度 + 表面肌电图　；参考：《苏州大学》2012年硕士论文

【摘要】：研究目的：膝关节是人们最重要的关节之一，而髌键末端病等膝关节病给人们的生活造成巨大困扰。髌腱是股四头肌的延续，而股四头肌是伸膝的主要装置，股四头肌的电机械应答对膝关节有重要影响。利用等速测力系统在不同膝关节角度下对股四头肌等长肌力测试，同时用表面肌电进行肌肉功能评价，用动作反应时测试系统进行肌肉激发时间分析，旨在探讨不同屈膝角度时股四头肌的电机械应答规律，以及疲劳对电机械应答规律的影响。研究方法：本实验采用等速测力系统，对10名受试者在不同膝关节角度进行最大等长伸膝测试，同时对股外侧肌、股内侧肌、股直肌进行表面肌电信号的采集与记录。分析不同膝关节角度时股四头肌的表面肌电变化特征和动作反应时变化特征，以及疲劳前后的变化。研究结果：（1）在等长伸膝模式中，从屈膝10°到屈膝90°，股四头肌的PT/BW在屈膝80°达到最大，有非常显著性差异（p0.01）。（2）在等长伸膝模式中，随着屈膝角度的增大，股四头肌的RT呈减小趋势，且具有非常显著性差异（p0.01）；股四头肌的PMT无显著性变化；股外侧肌、股内侧肌和股直肌的EMD均逐渐减小，有非常显著性差异（p0.01）。（3）在等长伸膝模式中，随着屈膝角度增大，iEMG的VM/VL先增大后减小，在屈膝40°达到最大，但无显著性差异（p0.05）；股外侧肌、股内侧肌和股直肌的iEMG%也无显著性差异，但同一角度情况下，在40°、50°、60°和90°时，三者有非常显著性差异（p0.01）。（4）疲劳后，股四头肌的PT无显著性变化；股外侧肌、股内侧肌和股直肌的PMT均较疲劳前减小，且股外侧肌和股直肌呈显著性差异（p0.05）；股外侧肌、股内侧肌和股直肌的EMD较疲劳前延长，股外侧肌和股直肌呈显著性差异（p0.05）。（5）疲劳后，iEMG的VM/VL较疲劳前减小，无显著性差异（p0.05）；股外侧肌和股内侧肌的iEMG%均较疲劳前减小，无显著性差异（p0.05），股直肌的iEMG%较疲劳前增大呈显著性差异（p0.05）；股内侧肌的放电贡献率最小，三者呈非常显著性差异（p0.01）。研究结论：（1）在一定的髋关节角度，从屈膝10°到屈膝90°的等长伸膝模式中，膝关节发挥伸膝最大力量的角度为屈膝80°。（2）股四头肌动作反应速度与膝关节角度有关，一定程度上，，屈膝角度越大产生运动的速度越快。（3）在不同膝关节角度，股四头肌各肌群的贡献率不同，在40°以后股外侧肌放电占主导。（4）疲劳是引起EMD延长的重要因素。
[Abstract]:Objectives of the study: Knee joint is one of the most important joints. Patellar tendon is the continuation of quadriceps femoris, and quadriceps femoris is the main device of knee extension. The electromechanical response of quadriceps femoris has an important effect on knee joint. The isokinetic force measurement system was used to measure the equal length muscle strength of quadriceps femoris at different angles of knee joint, the muscle function was evaluated by surface electromyography, and the time of muscle stimulation was analyzed by action reaction time test system. The aim of this study was to investigate the electromechanical response of quadriceps femoris at different flexion angles and the effect of fatigue on electromechanical response. Research methods: In this experiment, the isokinetic force measurement system was used to test the maximal isometric extension of knee at different knee angles in 10 subjects, and the surface electromyography (EMG) signals of lateral femoral muscle, medial femoral muscle and rectus femoris muscle were collected and recorded. The changes of surface electromyography and movement response of quadriceps femoris at different knee angles were analyzed. The changes before and after fatigue were also analyzed. Results of the study: The PT/BW of quadriceps femoris reached the maximum at 80 掳from 10 掳to 90 掳in the isometric extension mode, and there was a significant difference between them (p 0.01). The RT of quadriceps femoris decreased with the increase of flexion angle, and the difference was significant (p0.01), the PMT of quadriceps femoris did not change significantly, the EMD of lateral femoris, medial femoral muscle and rectus femoris decreased gradually. There was a very significant difference (P 0.01). In the isometric extension mode, the VM/VL of EMG first increased and then decreased with the increase of flexion angle, and reached the maximum at 40 掳, but there was no significant difference (p0.05), and there was no significant difference in the VM/VL% of lateral, medial and rectus femoris, but at the same angle, there was no significant difference in iEMG% between the lateral, medial and rectus femoris, but at the same angle, there was no significant difference between the two groups. There was a significant difference among the three groups at 40 掳, 50 掳, 60 掳and 90 掳. (4) after fatigue, PT of quadriceps femoris did not change significantly, the PMT of lateral femoral muscle, medial femoral muscle and rectus femoris muscle decreased compared with those before fatigue, and there was significant difference between lateral femoral muscle and rectus femoris muscle (p0.05), lateral femoral muscle, medial femoral muscle and rectus femoris muscle. The EMD of medial femoral muscle and rectus femoris muscle was longer than that before fatigue, and the difference between lateral femoral muscle and rectus femoris muscle was significant (p0.05). (5) after fatigue, the VM/VL of iEMG was lower than that of before fatigue, and the VM/VL% of lateral and medial femoral muscles was lower than that of before fatigue. The iEMG% of rectus femoris muscle was significantly higher than that of before fatigue, and the contribution rate of medial femoral muscle was the smallest (P 0.01). The study concluded that: 1) in a certain hip joint angle, the angle of maximum strength of knee joint is 80 掳in the mode of equal-length extension from 10 掳to 90 掳of knee flexion. 2) the reaction speed of quadriceps femoris is related to the angle of knee joint, to a certain extent, the greater the flexion angle, the faster the speed of motion. 3) the contribution rate of quadriceps femoris muscle group was different at different knee angle, and the discharge of lateral femoral muscle dominated after 40 掳. Fatigue is an important factor in prolonging EMD.
【学位授予单位】：苏州大学
【学位级别】：硕士
【学位授予年份】：2012
【分类号】：G804.2

【参考文献】