Understanding the Mechanical Underpinnings of Rotator Cuff Tear and Surgical Repair

项目摘要 肩袖损伤影响450万美国人，肩袖损伤患病率的增加与 随着年龄的增长。每年约有25万例肩袖修复手术， 美元的经济成本。肩袖是至关重要的日常生活活动，因此损害 会限制独立性和生活质量。肩袖撕裂通常采用手术治疗， 肌腱的重新附着;然而，由于再撕裂的可能性很高，手术并不总是可取的。高 在再附着手术期间的修复张力不仅在修复期间具有技术挑战性， 术后再撕裂、功能受限和/或由于关节接触改变导致的肩关节不稳定 力.因此，一种预测修复张力的方法可以在手术选择中发挥关键作用。修复张力为 术中测量;因此，它不能为手术决策提供信息。外科医生目前必须选择 基于与不良结局相关的其他MR成像参数进行手术修复的患者 严重受伤。在肩袖损伤后，肌肉-肌腱单元发生生理变化 包括回缩、肌肉萎缩和肌内脂肪和纤维组织增加。但目前尚不清楚 修复张力与三个主要临床参数之间是否存在直接关系 用于确定手术候选人（肌内脂肪、肌肉萎缩和收缩）。鉴于财政 与手术干预相关的成本和患者经历的身体负担， 需要了解影响肩袖损伤和修复张力的因素， 手术患者的护理水平，从而积极影响数百万美国人的生活质量。我们的整体 目的是了解肩袖修复的机械基础，以确定 生理变化和术后结果。这项研究将提供所需的关键信息， 告知手术成功的可能性并更好地预测手术结果，从而指导 肩袖修复手术实践标准。这项研究结合了实验和 计算框架（1）确定肩袖损伤引起的生理 变化和修复张力，以及（2）确定如何生理变化，由于肩袖损伤和升高 修复张力影响术后结果。

Project Summary Rotator cuff injuries affect 4.5 million Americans and the increase in prevalence of rotator cuff injuries correlates with increasing age. Around 250,000 rotator cuff repairs are performed each year, equating to over three billion dollars in economic cost. The rotator cuff is critically important in activities of daily living, and therefore damage to the rotator cuff can limit independence and quality of life. Rotator cuff tears are commonly treated with surgical reattachment of the tendon; however, surgery is not always advisable due to the high probability of retear. High repair tension during reattachment surgery is not only technically challenging during repair but also is often followed by post-surgical retear, limited functional capacity, and/or shoulder instability due to altered joint contact forces. Thus, a method to predict repair tension could play a key role in surgical selection. Repair tension is intraoperatively measured; therefore, it cannot inform the decision to operate. Surgeons currently must select patients for surgical repair based on other MR imaging parameters associated with poor outcomes and more severe injury. Following injury of the rotator cuff, the muscle-tendon unit undergoes physiological changes including retraction, muscle atrophy, and increased intramuscular fat and fibrous tissue. However, it is unclear whether there is a direct relationship between repair tension and the three main clinical parameters typically used for determining surgical candidacy (intramuscular fat, muscle atrophy, and retraction). Given the financial costs associated with surgical intervention and the physical burden experienced by patients, an improved understanding of the factors that influence rotator cuff injury and repair tension are needed to provide a higher level of care for surgery patients, thus positively impacting the quality of life for millions of Americans. Our overall objective is to understand the mechanical underpinnings of rotator cuff repair to identify relationships between physiological changes and post-surgical outcomes. This research will provide crucial information needed to inform likelihood of surgical success and better predict surgical outcomes, thereby guiding development of a standard of practice for rotator cuff repair surgery. The proposed research combines an experimental and computational framework to (1) determine the relationship between rotator cuff injury-induced physiological changes and repair tension, and (2) determine how physiological changes due to rotator cuff injury and elevated repair tension influences post-surgical outcomes.