Tsang Sharon M H, Szeto Grace P Y, Li Linda M K, Wong Dim C M, Yip Millie M P, Lee Raymond Y W
Department of Rehabilitation Sciences, The Hong Kong Polytechnic University, Hung Hom, Hong Kong.
Biomechanics, School of Applied Sciences, London South Bank University, London, UK.
BMC Musculoskelet Disord. 2017 Apr 17;18(1):157. doi: 10.1186/s12891-017-1515-3.
Impaired lumbo-pelvic movement in people with low back pain during bending task has been reported previously. However, the regional mobility and the pattern of the lumbo-pelvic movement were found to vary across studies. The inconsistency of the findings may partly be related to variations in the speed at which the task was executed. This study examined the effects of bending speeds on the kinematics and the coordination lumbo-pelvic movement during forward bending, and to compare the performance of individuals with and without low back pain.
The angular displacement, velocity and acceleration of the lumbo-pelvic movement during the repeated forward bending executed at five selected speeds were acquired using the three dimensional motion tracking system in seventeen males with low back pain and eighteen males who were asymptomatic. The regional kinematics and the degree of coordination of the lumbo-pelvic movement during bending was compared and analysed between two groups.
Significantly compromised performance in velocity and acceleration of the lumbar spine and hip joint during bending task at various speed levels was shown in back pain group (p < 0.01). Both groups displayed a high degree of coordination of the lumbo-pelvic displacement during forward bending executed across the five levels of speed examined. Significant between-group difference was revealed in the coordination of the lumbo-pelvic velocity and acceleration (p < 0.01). Asymptomatic group moved with a progressively higher degree of lumbo-pelvic coordination for velocity and acceleration while the back pain group adopted a uniform lumbo-pelvic pattern across all the speed levels examined.
The present findings show that bending speed imposes different levels of demand on the kinematics and pattern of the lumbo-pelvic movement. The ability to regulate the lumbo-pelvic movement pattern during the bending task that executed at various speed levels was shown only in pain-free individuals but not in those with low back pain. Individuals with low back pain moved with a stereotyped strategy at their lumbar spine and hip joints. This specific aberrant lumbo-pelvic movement pattern may have a crucial role in the maintenance of the chronicity in back pain.
先前已有报道称，下背痛患者在弯腰任务中腰骨盆运动受损。然而，研究发现腰骨盆运动的局部活动度和模式在不同研究中存在差异。研究结果的不一致可能部分与任务执行速度的变化有关。本研究考察了弯腰速度对前屈过程中腰骨盆运动学及协调性的影响，并比较了有和没有下背痛个体的表现。
使用三维运动跟踪系统，采集了17名下背痛男性和18名无症状男性在以五种选定速度重复前屈过程中腰骨盆运动的角位移、速度和加速度。比较并分析了两组之间弯腰过程中的局部运动学及腰骨盆运动的协调程度。
下背痛组在不同速度水平的弯腰任务中，腰椎和髋关节的速度及加速度表现明显受损（p < 0.01）。在五个检查速度水平的前屈过程中，两组腰骨盆位移均表现出高度协调性。腰骨盆速度和加速度的协调性存在显著组间差异（p < 0.01）。无症状组在速度和加速度方面腰骨盆协调性程度逐渐增加，而下背痛组在所有检查速度水平上采用统一的腰骨盆模式。
目前的研究结果表明，弯腰速度对腰骨盆运动学及模式有不同程度的要求。只有无痛个体能够在以不同速度水平执行的弯腰任务中调节腰骨盆运动模式，但下背痛个体则不能。下背痛个体在腰椎和髋关节处采用刻板的策略进行运动。这种特定的异常腰骨盆运动模式可能在维持慢性背痛方面起关键作用。
