Trunk muscle control of human lumbar spine stability

脊柱是一个非常复杂的生物和机械结构。腰椎特别容易受伤和疼痛，一直是大量研究的重点，这些研究试图了解腰椎的运作方式，以及工作和日常活动如何导致组织损伤。当负荷被处理时，身体必须找到一种方法来使用脊椎的许多肌肉和韧带来执行任务，并且必须考虑一些目标。首先，我们希望将代谢成本保持在较低水平。接下来，我们需要从成功完成任务的大量肌肉力量组合中进行选择。最后，我们必须招募肌肉，使腰椎保持一定程度的稳定，使其不会弯曲。通常，这三个对象相互冲突。这项研究的目的是加深我们对身体如何解决这三个不同目标的理解，特别是在各种负荷条件下，机械脊柱稳定性所起的作用。特别是，突然的躯干负荷和长时间的疲劳任务被发现是研究脊柱稳定性的特别好的干扰因素。我们计划使用各种不同类型的扰动来挑战脊柱，并进一步了解如何保持稳定性以避免受伤。首先，我们必须进一步完善脊柱的复杂计算机模型，包括它的肌肉、脊椎和韧带。该模型将允许计算脊柱最低的六个关节和三个解剖轴线(屈曲/伸展、侧弯、轴向扭转)的稳定性。接下来，我们将使用这个模型和肌肉肌电图仪来预测各种躯干扰动对个体肌力和稳定性的贡献。受试者将通过快速施加在胸带上的力、手持载荷以及他们将坐在上面的机器人平台的移动而暴露在突然和长期的载荷中。拟议研究的长期目标是通过进一步了解躯干肌肉对腰椎力学的贡献来减少下背部损伤。

The spine is a very complex biological and mechanical structure. The lumbar spine, or low back, is particularly susceptible to injury and pain and has been the focus of a great deal of research attempting to understand how it operates and how work and everyday activities can lead to tissue damage. When loads are handled, the body must find a way to use the many muscles and ligaments of the spine to perform the task with a number of objectives that must be considered. First, we want to keep the metabolic cost low. Next, we need to select from a large number of combinations of muscle forces that will successfully complete the task. Finally, we must recruit muscles that will maintain some level of stability in the lumbar spine so that it does not buckle. Often, these three objects conflict with each other. The purpose of this research is to further our understanding of how the body resolves these three different objectives and, in particular, what role mechanical spine stability plays under a variety of loading conditions. In particular, sudden trunk loading and prolonged, fatiguing tasks have been found to be particularly good perturbations for studying spine stability. We plan to use a variety of these types of perturbations to challenge the spine and further our knowledge of how we maintain stability in an effort to avoid injury. First, we will have to further refine a complex computer model of the spine, including its muscles, vertebrae and ligaments. This model will allow for stability to be calculated about the lowest six joints of the spine and about each of the three anatomical axes (flexion/extension, lateral bend, axial twist). Next, we will use this model and muscle electromyography to predict individual muscle forces and stability contributions for a wide variety of trunk perturbations. Subjects will be exposed to sudden and prolonged loading through force rapidly applied to a chest harness, to hand held loads and through movement of a robotic platform on which they will sit. The long term objective of the proposed research is to reduce low back injuries through a further understanding of trunk muscle contributions to lumbar spine mechanics.