外侧腹部肌群在骨盆运动控制中的作用机制及其在"骨盆带疼痛"中的变化

As a special subgroup of low back pain, pelvic girdle pain (PGP) has drawn more and more attentions in western countries,but almost none in China. In a systematic review in 2004, Wu et al.observed that the far majority of PGP cases are related to pregnancy, with complaints starting during or shortly after pregnancy. Wu et al.coined this syndrome "pregnancy-related pelvic girdle pain (PPP)", and reported that about 45% of all pregnant women and 25% of all postpartum women suffered from PPP and/or pregnancy-related low back pain.. The pathophysiological mechanisms underlying PGP remain poorly understood. A variety of etiologic factors have been proposed, such as hormonal and biomechanical factors associated with pregnancy, and problems with motor control.. Pelvic girdle is the only structure between trunk and the lower extremities. Due to its internal instability, it needs active motor control to generate force closure on pelvic to get a stable situation. The lateral abdominal muscles do play the main role on this force closure. The applicant's previous biomechanical studies on pelvic girdle via the tasks of the Active Straight Leg Raise test and tradmill walking have proved the theory of force closure. Futhermore, we found that even a single task, the motor control needs fine coordination of all segments of the body and related musles in three dimensional space.However, due to the small movement of pelvis, it is hard to detect by routine movement caputer system, acquiring more evidences of kinematics and kinetics. . As to the patients of pelvic girdle pain, in comparison with normal peers, the project forcuses on the study of the control changes of abdominal muscles by measuring ultrasound and fine wire EMG as well as kinematic and kinetic parameters, trying to find out the biomechanic mechanism of normal pelvic girdle and the pathological mechanism of pelvic girdle pain. These finding would provide theoretical evidence for the futher classification of diagnosis and lead to an appropriate treatment.

骨盆带疼痛作为下腰痛的一种特殊类型，在妊娠妇女的发病率约45%，而产后妇女的发病率多达25%。它病因复杂，其中之一是生物力学因素。骨盆带作为连接躯干和下肢的唯一结构，存在内在解剖不稳定性，需要主动的运动控制对骨盆形成动力锁合,才能达到骨盆带的稳定，其中外侧腹部肌群对产生动力锁合起主要作用。近年来，本项目负责人从仰卧位单侧直腿抬高实验和站立位行走实验入手进行的生物力学研究，证实了这一理论，并发现即使简单的动作，运动控制也需要全身各节段和肌肉之间在三维空间进行精密协调。然而，骨盆的活动度较小，仍缺乏足够的运动学和动力学证据。本项目针对骨盆带疼痛的病人，对比正常人群，致力于进一步研究外侧腹部肌群在骨盆运动控制中的作用机制，应用B超及细丝肌电图技术获得腹部肌肉形态学和肌电图数据，结合运动学和动力学资料，旨在阐明外侧腹部肌群在骨盆运动控制中的作用机制和病理机制，为骨盆带疼痛的诊断和治疗提供理论依据。

骨盆带疼痛作为下腰痛的一种特殊类型，在妊娠妇女的发病率约45%，而产后妇女的发病率多达25%。它病因复杂，其中之一是生物力学因素。骨盆带作为连接躯干和下肢的唯一结构，其生物力学的病理特征是引起骨盆带疼痛的重要因素。. 本项目针对骨盆带疼痛的病人，对比正常人群，就步行机上行走和仰卧位主动直腿抬高试验，应用超声及细丝和表面肌电图技术获得腹部肌肉形态学和肌电图数据，结合运动学和动力学资料进行分析，致力于研究外侧腹部肌群在骨盆运动控制中的作用机制。. 研究发现： 1)正常情况下，髋-骨盆-腰的协调动作保证了人正常的功能活动； 2)而在骨盆带疼痛患者中，骨盆不仅在矢状面不能协调动作（骨盆前倾增加），而且在横截面和冠状位也不能协调运动（同向旋转和侧偏增加）；3）腹横肌收缩力量减弱是造成骨盆带疼痛的主要原因之一，相比腰痛患者外侧腹部肌群收缩力量均减弱；4）曾有剖腹产史的骨盆带疼痛患者，腹横肌超声下的最大横截面积及厚度和肌电图幅度明显缩小。. 总之，外侧腹部肌群在骨盆的运动控制中起到重要的作用，其肌电图变化也是鉴别骨盆带疼痛和下腰痛的主要特征；对于孕产妇尽量少用剖腹产或需要仔细分层缝合。