Shoulder, low back, or knee strength degradation

描述（由申请人提供）：本研究的总体目标是系统地调查三个主要身体关节（肩关节、下背部和膝关节）的强度退化是否以及如何影响与手动材料处理性能相关的运动策略和损伤风险。我们的长期目标是开发定量工具和指南，整合运动和力量信息，用于识别，预测和预防职业性肌肉骨骼损伤。这项拟议的研究项目旨在实现以下具体目标： (1)评估人类受试者的力量，并通过分析获得的力量曲线，建立四个受试者组，一个症状对照组和三组选择性降低肩部，腰部或膝盖力量的个体。 (2)在不同的任务条件下（通过系统地改变任务参数，如处理的负载，不对称角，目的地位置），测量由四组受试者执行的模拟手动材料处理任务期间的三维运动。 (3)使用高保真全身生物力学联动表示对测量的运动进行建模，并通过确定各种测量运动中的主动自由度，来检查假设的全身关节运动激活模式变化。 (4)使用基于优化的微分逆运动学（ODIK）方法对测量的运动进行建模，从而可视化假设的全身关节间运动分配策略畸变。 (5)为了使用逆动力学驱动的直接动力学（ID 4）方法对测量的运动进行建模，从而深入了解假设的运动学畸变的动力学原因，并检查力矩允许量的假设变化（即，“力量储备”）和受伤的风险。 成功完成此项目将导致：（1）基于运动的肌肉力量退化评估，以进行积极的人机工程学干预，重返工作评估和康复人机工程学实施;（2）用于设计消费品或工作场所的指南和计算机模拟模型，以更好地适应力量能力退化的特殊人群;以及（3）更好地理解肌肉力量如何影响运动控制策略，从而在特定的和一般的人体运动中的手动材料处理任务期间的损伤风险。

DESCRIPTION (provided by applicant): The general objective of this research is to systematically investigate whether and how strength degradation in three major body joints--the shoulder, low back, and knee--affects the movement strategies and injury risk associated with the performance of manual materials handling. Our long-term goal is to develop quantitative tools and guidelines that integrate movement and strength information for the recognition, prediction, and prevention of occupational musculoskeletal injuries. This proposed research project seeks to accomplish the following specific aims: (1) To evaluate the strengths of human subjects, and through analysis of acquired strength profiles, to establish four subject groups one a symptomatic control group and three groups of individuals with selectively degraded shoulder, low back, or knee strength. (2) To measure three-dimensional movements during simulated manual materials handling tasks performed by the four groups of subjects under various task conditions (created by systematically varying task parameters such as load handled, angle of asymmetry, destination location). (3) To model the measured movements using a high-fidelity whole-body biomechanical linkage representation, and through determination of the active degrees of freedom in various measured movements, to examine the hypothesized whole-body joint motion activation pattern change. (4) To model the measured movements using an optimized-based differential inverse kinematics (ODIK) approach, and thus to visualize the hypothesized whole-body inter-joint motion apportionment strategy aberration. (5) To model the measured movements using an inverse-dynamics-driven direct dynamics (ID 4) approach, and thus to gain insight into the kinetic cause for hypothesized kinematics aberration and examine hypothesized changes in moment allowance (i.e., "strength reserve") and risk of injury. A successful completion of this project will lead to: (1) Motion-based evaluation of muscle strength degradation for proactive ergonomics intervention, return-to-work assessment, and rehabilitative ergonomics implementation; (2) Guidelines and computerized simulation models for designing consumer products or workplaces to better accommodate special population with degraded strength capability; and (3) A better understanding of how muscle strength influences the motion control strategies and consequently the injury risk during manual materials handling tasks in specific and human movements in general.