Movement compensation after rotator cuff tear: What is safe and what is risky?

肩袖撕裂是一种常见的肌肉骨骼损伤，影响了超过一半的60岁以上的成年人。这种损伤是致残的，因为它破坏了肩部肌肉力量的分布，导致个人在执行功能性任务时产生代偿性运动。其中一些补偿可能会造成继发性损伤的风险，但补偿策略与继发性损伤风险之间的关系尚不清楚。该项目的目标是开发一个健壮的肩部计算模型，以研究肩袖撕裂对运动补偿和损伤风险的影响。使用该模型进行的分析结果将突出康复策略设计的目标，以不增加继发性损伤风险的方式促进运动补偿。研究成果还将转化为大学和K-12级别的教育推广活动，包括在课堂上采用建模活动，并与当地高中教师合作开展教师研究经验，进一步扩大这项工作的影响。建立一个模型将有助于我们提高对肩袖撕裂的功能影响的理解，包括运动补偿和继发性肩伤风险。这些结果将使美国数百万因肩袖撕裂而运动受限和继发性损伤的成年人受益。本研究的目的是开发和验证肩部复合体的计算肌肉骨骼模型，以表征上肢运动并确定肩袖撕裂后损伤的机制。现有的模型没有捕捉到肩关节复合体的所有关节（肩胛骨-胸椎、肩胛-肱骨平移）和软组织（韧带）的作用，而这些是充分理解损伤影响所必需的。为了实现这一目标，目前的项目将开发一个肩关节复合体的仿生计算肌肉骨骼模型，包括关节关节和软组织结构的详细描述。将使用该模型进行模拟，以表征肩袖撕裂情况下的运动补偿，并检查补偿与继发性损伤风险之间的关系。这里开发的建模工具将用于告知我们对肩袖撕裂的功能影响的理解，并暴露康复目标。该模型将通过开源软件平台提供给社区，为生物力学社区提供一个显着的进步，并扩大这项工作的影响。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

Rotator cuff tear is a common musculoskeletal injury that affects more than half of adults over the age of 60 years. This injury is disabling because it disrupts the distribution of muscle forces at the shoulder, causing individuals to develop compensatory movements when performing functional tasks. Some of these compensations could pose a risk for a secondary injury, but the associations between compensation strategies and secondary injury risk are not clear. The goal of this project is to develop a robust computational model of the shoulder to study the effect of a rotator cuff tear on movement compensation and injury risk. Outcomes from analyses performed with the model will highlight targets for design of rehabilitation strategies that promote movement compensation in ways that do not increase secondary injury risk. Research outcomes will also be translated into educational outreach activities at the University and K-12 levels, including adoption of modeling activities in the classroom and partnering with a local high school teacher for a Research Experience for Teachers, further broadening the impact of this work. Developing a model will help us improve our understanding of the functional effects of rotator cuff tear, including movement compensation and secondary shoulder injury risk. These outcomes will benefit the millions of adults in the US who experience movement limitations and secondary injury due to a rotator cuff tear.The objectives of this study are to develop and validate a computational musculoskeletal model of the shoulder complex to characterize upper limb movement and identify mechanisms of injury after a rotator cuff tear. Existing models do not capture all articulations (scapulo-thoracic, glenohumeral translation) and soft tissue (ligament) contributions at the shoulder complex that are needed to fully understand the implications of injury. To achieve this, the current project will develop a biofidelic computational musculoskeletal model of the shoulder complex that includes detailed descriptions of joint articulations and soft tissue structures. Simulations with the model will be performed to characterize movement compensation in the context of rotator cuff tear and examine the associations between compensation and secondary injury risk. The modeling tool developed here will be used to inform our understanding of the functional effects of rotator cuff tear and expose targets for rehabilitation. This model will be made available to the community through an open-source software platform, providing a notable advancement for the biomechanics community and broadening the impact of this work.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.