• ➤ Dual mobility (DM) refers to a now widely available option for total hip articulation. DM implants feature a small inner head, a hard bearing, that connects via a taper fit onto the femoral trunnion. This head freely rotates but is encased inside a larger, outer polyethylene head that articulates with a smooth acetabular component.
• ➤ DM acetabular components are available in the form of a monoblock shell or as a liner that is impacted into a modular shell, providing a metal articulation for the polyethylene outer head.
• ➤ DM is designed to increase hip stability by providing the arthroplasty construct with a higher jump distance, head-to-neck ratio, and range of motion prior to impingement.
• ➤ The use of DM in total hip arthroplasty continues to increase in the United States for both primary and revision arthroplasty. Surgeons should be aware of the potential benefits and pitfalls.
• ➤ Long-term data are lacking, especially for modular DM implants. Points of concern include a potential for accelerated polyethylene wear, intraprosthetic dislocation, and modular backside fretting corrosion.

中文翻译：

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双活动部件在全髋关节置换术中的作用

• ➤ 双活动度 (DM) 是指现在广泛使用的全髋关节活动选项。DM 植入物具有一个小的内头，一个硬轴承，通过锥形配合连接到股骨耳轴上。这个头部可以自由旋转，但被包裹在一个更大的外部聚乙烯头部内，该头部与一个光滑的髋臼组件连接在一起。
• ➤ DM 髋臼组件以整体式外壳的形式提供，也可以作为嵌入模块化外壳的衬里形式提供，为聚乙烯外头提供金属关节。
• ➤ DM 旨在通过为关节置换术结构提供更高的跳跃距离、头颈比和碰撞前的运动范围来提高髋关节稳定性。
• ➤ 在美国，无论是初次关节置换术还是翻修术，DM 在全髋关节置换术中的使用持续增加。外科医生应该意识到潜在的好处和陷阱。
• ➤ 缺乏长期数据，尤其是模块化 DM 植入物。关注点包括加速聚乙烯磨损、假体内脱位和模块化背面微动腐蚀的可能性。