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和有效完成上肢任务的关键。虽然在神经肌肉损伤后，我们在躯干的帮助下完成这些任务的能力经常受到损害，但描述躯干神经力学功能的理论工具，以及衍生的定量见解，仍然不如下半身的研究。然而，这些见解对于推动技术创新至关重要，这些技术创新可以恢复受损后的躯干功能。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，使神经肌肉损伤的人在日常生活中能够稳定他们的躯干。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)利用模型获得躯干动态姿态和上肢功能的定量神经力学图；(3)系统识别脊柱电刺激参数，优化坐姿时躯干的动态稳定性。在子程序1中，我的团队将使用Visible Human Project的女性和男性数据集来获取肌肉骨骼参数，用于运动学、动力学和肌肉建模。利用这些参数，我们将开发详细的、性别特异性的上肢神经力学模型，充分考虑上肢的运动，并可针对特定个体进行调整。这些模型将允许我的团队在子程序2中建立一个躯干神经力学的定量地图，该地图可以解释年龄、性别和感觉运动限制。通过我们的神经力学模型，从一组姿势恢复和先前验证的上肢任务中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肉力。在子项目3中，我们将首先对俯卧和直立姿势的健康年轻人进行无创脊柱刺激，系统地确定刺激参数，使刺激对神经机械躯干测量的影响最大化。其次，将优化后的刺激参数应用于健康的年轻个体，量化刺激对意外支持基础扰动下坐姿躯干稳定性和姿势恢复的影响。尽管躯干在日常活动中很重要，但缺乏完整的神经力学特征以及量化和恢复其功能的有效工具。该计划将通过使用机械工具揭示姿势和上肢功能中躯干神经力学的性别特异性复杂性来提高我们的知识；并通过确定有效的脊柱刺激参数来恢复动态姿态下的躯干功能。这些贡献将推动未来的创新，转化为有效的康复策略和上半身仿生神经假体。

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.