A novel thermodynamic bone remodeling framework for artificial joint optimization

人工关节假体用于替代患病的关节表面并减轻患者的疼痛。经过大约 10 年的使用后，这些人工关节通常会导致严重的并发症，例如骨再骨折、感染和植入失败。这些失败的种植体需要通过昂贵的翻修手术来替换，与初次替换相比，翻修手术更加困难，结果也不太令人满意。这些并发症与关节表面磨损颗粒的产生以及骨损失（也称为骨-植入物界面处的骨重塑）有关。这种骨重塑是人工关节置换术中的一个主要问题，特别是对于患有骨质疏松症或骨关节炎的老年患者。目前，大多数用于关节置换的植入物都是由钛和钴铬合金等刚性材料制成。这种植入物的使用改变了骨内的应力水平，导致植入物附近的骨重塑。 因此，了解、监测和控制种植体周围发生的重塑非常重要。这项研究的目的是通过开发、实施和验证骨重塑的先进数学框架来改进关节植入物的设计。这种独特的数学框架使用不可逆热力学来结合所有因素，机械和代谢（生物和化学），这些因素在骨骼重塑过程中同时发挥作用。这种先进的模型在预测骨重塑和患者治疗方面具有多种潜在应用。短期内，它将有助于改进金属和仿生假肢的设计。它还将用于评估和监测全髋关节置换术和髋关节表面置换术等外科手术后骨再骨折的风险。从长远来看，它可以为与骨吸收相关的骨疾病（例如骨质疏松症）的虚拟模拟奠定基础，这将有助于开发新的治疗策略。

Artificial joint prostheses are used to replace diseased articular surfaces and provide pain relief for patients. After approximately 10 years of service, these artificial joints often cause major complications such as, bone re-fracture, infection and implant failure. These failed implants need to be replaced through costly revision surgeries, that are more difficult with less satisfactory outcomes compared to the primary replacement. These complications have been linked to the production of wear particles at the articular joint surface and bone loss also known as bone remodeling at the bone-implant interface. This bone remodeling is a major issue in artificial joint replacement particularly for elderly patients suffering from osteoporosis or osteoarthritis. Currently, most implants used in joint replacements are made from stiff materials such as titanium and cobalt-chrome alloys. The use of such implants changes the levels of stress within the bone, resulting in bone remodeling adjacent to the implant. Therefore, it is important to understand, monitor and control the remodeling that occurs around implants. The aim of this research is to improve the joint implants design by developing, implementing and validating an advanced mathematical framework for bone remodeling. This unique mathematical framework uses irreversible thermodynamics to combine all factors, mechanical, and metabolic (biological and chemical) which are simultaneously at play in the bone remodeling process. This advanced model has multiple potential applications in predicting bone remodeling and patient therapy. In the short term, it will assist in improving the design of metallic and biomimetic prostheses. It will also be used to assess and monitor the risk of bone re-fracture after surgical procedures such as total hip and hip resurfacing arthroplasty. Over the long term it can form a basis for virtual simulations of bone diseases associated with bone resorption such as osteoporosis, which will allow for the development of new therapeutic strategies.