Novel Approaches for Modeling, Mapping, and Restoring Human Trunk Neuromechanics

能够动态稳定人体躯干是保持姿势平衡、有效完成上肢任务的关键。虽然我们在躯干帮助下执行这类任务的能力在神经肌肉损伤后往往会受到影响，但用于表征躯干神经机械功能的理论工具以及由此得出的量化见解仍然不如下半身研究中的工具。然而，这种洞察力对于推动技术创新至关重要，这些创新可以在损伤后恢复躯干功能。在我过去工作的基础上，这个项目的长期目标是创造有效的技术，使患有神经肌肉损伤的人能够在日常生活中稳定他们的躯干。我的中短期目标是：(1)开发针对性别的上半身神经力学模型；(2)使用这些模型获得躯干在动态姿势和上肢功能时的定量神经力学图；(3)系统地确定脊柱电刺激的参数，以优化躯干在坐姿时的动态稳定性。在子项目1中，我的团队将使用可见人项目的女性和男性数据集来获取用于运动学、动力学和肌肉建模的肌肉骨骼参数。使用这些参数，我们将开发详细的、针对性别的上半身神经力学模型，该模型充分考虑上肢的运动，并可以根据特定的个人进行调整。这些模型将允许我的团队在子程序2中建立躯干神经力学的量化地图，该地图考虑了年龄、性别和感觉运动限制。通过我们的神经力学模型，为一系列姿势恢复和先前验证的上肢任务获得的实验数据将用于量化、关联和可视化躯干运动学和力矩以及肌力。在子计划3中，我们将首先对处于俯卧和直立姿势的健康年轻人进行非侵入性脊柱刺激，以系统地确定刺激参数，使刺激对神经机械躯干措施的影响最大化。其次，优化的刺激参数将用于健康的年轻人，以量化刺激对坐姿躯干稳定性和在意外的支撑底座扰动时姿势恢复的影响。尽管躯干在日常活动中很重要，但缺乏对躯干的完整神经力学特征以及量化和恢复其功能的有效工具。这项计划将通过使用机械工具揭示躯干神经力学在姿势和上肢功能方面的特定性别的错综复杂，以及通过确定有效的脊椎刺激参数来恢复动态姿势下的躯干功能，从而提高我们的知识。这些贡献将推动未来的创新，转化为有效的康复战略和上半身的仿生神经假体。

Being able to dynamically stabilize the human trunk is key for maintaining postural balance and effectively completing upper limb tasks. While our ability to perform such tasks with the trunk's assistance is often compromised following neuromuscular impairment, theoretical tools for characterizing the neuromechanical function of the trunk, and derived quantitative insights, are still inferior to those in lower body research. Such insights, however, are crucial for driving technological innovations that can restore trunk function following impairment. Building on my past work, this program's long-term goal is to create effective technologies that enable individuals with neuromuscular impairments to stabilize their trunk in daily living. My short- to mid-term objectives are to: (1) develop sex-specific, neuromechanical models of the upper body; (2) use the models to obtain a quantitative neuromechanical map of the trunk in dynamic posture and upper limb function; and (3) systematically identify parameters for electrical spine stimulation that optimize the trunk's dynamic stability during seated posture. In Subprogram 1, my team will use the female and male datasets of the Visible Human Project to obtain musculoskeletal parameters for kinematic, dynamic, and muscle modeling. Using the parameters, we will develop detailed, sex-specific neuromechanical models of the upper body that fully consider the movement of the upper limbs and can be tuned to specific individuals. The models will allow my team to establish, in Subprogram 2, a quantitative map of trunk neuromechanics that accounts for age, sex, and sensorimotor constraints. Experimental data obtained for a set of postural recovery and previously validated upper limb tasks will be used to quantify, correlate, and visualize trunk kinematics and moments as well as muscle forces via our neuromechanical models. In Subprogram 3, we will first apply non-invasive spine stimulation to healthy young individuals in prone and upright positions, to systematically identify stimulation parameters that maximize the stimulation's effect on neuromechanical trunk measures. Second, the optimized stimulation parameters will be used in healthy young individuals to quantify the stimulation's influence on seated trunk stability and postural recovery during unexpected base-of-support perturbations. Despite the trunk's importance in daily activities, a complete neuromechanical characterization of the trunk and effective tools for quantifying and restoring its function are lacking. This program will advance our knowledge by uncovering the sex-specific intricacies of trunk neuromechanics in postural and upper limb function using mechanistic tools; and by identifying effective spine stimulation parameters for restoring trunk function in dynamic posture. These contributions will drive future innovations that translate into effective rehabilitation strategies and bionic neuroprostheses for the upper body.