Compliant Shape Memory Polymer Device for Meniscal Repair

描述（由申请人提供）：该项目的目标是开发基于形状记忆聚合物的兼容半月板修复装置。修复装置将插入一个侵入性较小的临时形状，然后触发扩展到其永久功能形状。半月板修复是一种越来越常见和关键的基于软组织的骨科手术。在美国，每年约有90万例手术，估计费用超过8600万美元。固定装置，如缝合线、钉和混合装置，通常用于半月板修复手术，以帮助促进组织愈合。对于由静态材料组成的器械，最小侵入和适当的生物力学性能的要求往往是相互排斥的。目前半月板修复装置最常见的失败报告包括装置错位和断裂，与半月板组织的顺应性不匹配，关节腔炎症和软骨损伤。提出的形状记忆半月板修复装置共同解决了半月板修复过程中使用的刚性钉和基于缝合线的装置相关的主要临床问题。该装置将以薄的形状插入，以便于插入和最小的组织损伤。该装置的两端将包括特定的几何设计特征，以在撕裂的组织末端内提供固定。利用设备材料的形状记忆特性，该设备将被触发，在撕裂部位扩展，并将两个撕裂组织的末端压缩在一起，以提供完整的组织与组织接触，以增强愈合。通过调整设备的几何形状，设备的顺应性将更紧密地与原始半月板组织对齐，这样半月板的生物力学不会发生剧烈改变。这个拟议的项目将通过两个具体目标来完成。目标1将涉及了解设备几何形状如何影响设备遵从性和形状记忆恢复特性。目标2将侧重于开发原型并在体外台式模型中测试其功能性能。第一阶段的成功完成将展示符合形状记忆修复设备的整体概念证明，并提供开发成功的商业设备所需的基础知识。

DESCRIPTION (provided by applicant): The objective of this project is to develop compliant meniscal repair devices based on shape memory polymers. The repair device will be inserted in a less invasive temporary shape and then triggered to expand into its permanent functional shape. Meniscus repair represents an increasingly common and critical soft-tissue based orthopedic procedure. Approximately 900,000 procedures are performed annually in the United States at an estimated cost of over $86 million. Fixation devices, such as sutures, tacks, and hybrid devices, are commonly used in meniscus repair procedures to help facilitate tissue healing. The requirements of minimal invasion and appropriate biomechanical properties are often mutually exclusive with devices comprised of static materials. The most common reported failures of current meniscal repair devices include device misplacement and breakage, compliance mismatch with meniscus tissue, inflammation of joint cavity, and chondral damage. The proposed shape memory meniscal repair device collectively addresses the primary clinical issues associated with both rigid tacks and suture-based devices used in meniscal repair procedures. The device will be inserted in a thin shape to allow for easy insertion and minimal tissue damage. Specific geometric design features will be included on both ends of the device to provide fixation within the torn tissue ends. Using the shape memory characteristics of the device material, the device will be triggered to expand across the tear site AND compress the two torn tissue ends together to provide complete tissue-to-tissue contact for enhanced healing. By tailoring the geometry of the device, the compliance of the device will be more closely aligned to native meniscus tissue such that the biomechanics of the meniscus are not drastically altered. This proposed project will be accomplished through two specific Aims. Aim 1 will involve understanding how device geometry impacts device compliance and shape memory recovery characteristics. Aim 2 will focus on developing prototypes and testing their functional performance in an in vitro benchtop model. The successful completion of the Phase I will demonstrate overall proof of concept for compliant shape memory repair devices as well as provide the fundamental knowledge needed to develop successful commercial devices. PUBLIC HEALTH RELEVANCE: This project can impact the estimated 900,000 patients who undergo meniscus repair annually in the United States. The goal of this project is to develop compliant shape memory repair devices that will improve the functional outcome for patients with torn menisci by offering a less invasive approach and more reliable healing.