From the Department of Orthopedic Surgery, Rainier Orthopedic Institute, Puyallup, WA (Vajapey) and the Department of Orthopaedic Surgery, Brigham and Women's Hospital, Boston, MA (Shah and Estok).
J Am Acad Orthop Surg. 2023 Feb 15;31(4):189-197. doi: 10.5435/JAAOS-D-22-00498. Epub 2023 Jan 11.
Trunnion in total hip arthroplasty refers to the interface between the neck of a femoral stem and the femoral head. Clinical complications arising from damage to this junction, whether it be due to mechanical wear, corrosion, or a combination, are referred to as mechanically assisted crevice corrosion (MACC), also commonly known as trunnionosis. With the use of modular hip prostheses, which help customize offset and leg length to an individual patient's anatomy, the incidence of MACC and revision due to MACC has increased in recent years. Although the cause of MACC is multifactorial, with patient factors and technique factors contributing to this condition, taper design and geometry, metallurgical properties of implants, and size mismatch of the bearing couple are some of the implant factors that have also been implicated in this clinical phenomenon. Understanding the history of taper design and geometry, the track record of older implants, and the rationale behind the development of current prostheses can help surgeons choose the right implants for their patients and accurately assess the pros and cons of new implants being introduced to the market each year.
在全髋关节置换术中，臼杯是指股骨柄颈部与股骨头之间的界面。由于这个连接点受到机械磨损、腐蚀或两者共同作用而导致的临床并发症被称为机械辅助缝隙腐蚀（MACC），也通常被称为臼杯病。近年来，随着使用模块化髋关节假体来帮助根据个体患者的解剖结构定制偏心距和下肢长度，MACC 的发生率和因 MACC 而进行的翻修手术有所增加。虽然 MACC 的原因是多因素的，与患者因素和技术因素有关，但锥度设计和几何形状、植入物的冶金特性以及轴承对的尺寸不匹配等植入物因素也与这一临床现象有关。了解锥度设计和几何形状的历史、旧植入物的记录以及当前假体开发背后的原理，可以帮助外科医生为患者选择合适的植入物，并准确评估每年引入市场的新型植入物的优缺点。
