Hermena Shady, Tawfeek Waleed, Latimer Paul
Trauma and Orthopaedics, Yeovil District Hospital NHS Foundation Trust, Yeovil, GBR.
Cureus. 2021 Nov 24;13(11):e19858. doi: 10.7759/cureus.19858. eCollection 2021 Nov.
Total hip arthroplasty (THA) is one of the most successful and widely accepted orthopedic procedures. Instability after THA is one of the most significant postoperative complications. Dual-mobility THA components were introduced in 1974 to overcome the risk of instability by increasing the jump distance. Dual-mobility bearings couple two articulations, namely, one between a 22-28 mm prosthetic head and polyethylene liner and another larger articulation between the polyethylene liner and the metal cup. Dislocation of the polyethylene liner and the consequent direct articulation between the prosthetic head and metal cup is recognized as intraprosthetic dislocation (IPD). This mode of THA failure is specific to dual-mobility implants. Despite the reduced incidence of IPD in modern dual-mobility implants compared to the early designs, iatrogenic IPD can occur during closed reduction of dislocated polyethylene liner-metal cup articulation. IPD requires timely diagnosis and early surgical intervention to minimize the necessity of major revision surgeries. This study presents a comprehensive review for dual-mobility-bearing THA, including the history and biomechanics, and focuses on the pathomechanics, diagnosis, and management of IPD.
全髋关节置换术（THA）是最成功且被广泛接受的骨科手术之一。THA术后不稳定是最严重的术后并发症之一。1974年引入双动全髋关节置换组件，通过增加跳跃距离来克服不稳定风险。双动轴承连接两个关节，即22 - 28毫米假体头与聚乙烯衬垫之间的一个关节，以及聚乙烯衬垫与金属杯之间另一个更大的关节。聚乙烯衬垫脱位以及随之而来的假体头与金属杯之间的直接关节活动被认为是假体内部脱位（IPD）。这种THA失败模式是双动植入物特有的。尽管与早期设计相比，现代双动植入物中IPD的发生率有所降低，但在脱位的聚乙烯衬垫 - 金属杯关节闭合复位过程中仍可能发生医源性IPD。IPD需要及时诊断和早期手术干预，以尽量减少进行大型翻修手术的必要性。本研究对双动轴承全髋关节置换术进行了全面综述，包括其历史和生物力学，并重点关注IPD的发病机制、诊断和管理。
