School of Engineering, Newcastle University, NE1 7RU, Newcastle upon Tyne, UK.
Freeman Hospital, Newcastle Upon Tyne, UK.
J Biomed Mater Res B Appl Biomater. 2022 Oct;110(10):2290-2298. doi: 10.1002/jbm.b.35077. Epub 2022 Jun 3.
Flanged acetabular cups were developed with the rationale that, at insertion, they would increase the pressure of the cement and improve penetration of cement into the acetabular bone. Various studies have been inconclusive regarding their effectiveness. In this work, we aimed to eliminate all confounding factors and measure the pressures generated during acetabular pressurization and cup implantation using a simplified steel acetabulum, high precision pressure transducers, proper surgical techniques and two acetabular cups, identical apart from the addition of a flange to one. It was found that the flanged acetabular component did not significantly increase the pressure in the acetabulum and in some cases reduced the pressures generated when compared to an unflanged cup. The addition of a flange did not reduce the pressure differential between the pole and the rim of the acetabulum, nor did it have a significant effect on pressure lost over the cup implantation period. It was concluded that flanged acetabular cups provide no significant improvement in the pressures generated in the acetabulum during acetabular cup implantation. It is hypothesized that the flange may be seen as a design feature intended to slow the insertion of the cup into the cement, thus requiring the surgeon to apply a larger load in order to correctly position the acetabular cup; in this way larger pressure will be generated.
带边髋臼杯的设计理念是，在插入时，它们会增加水泥的压力，并改善水泥在髋臼骨中的渗透。然而，各种研究对其效果的结论并不一致。在这项工作中，我们旨在消除所有混杂因素，并使用简化的钢髋臼、高精度压力传感器、适当的手术技术和两个髋臼杯来测量髋臼加压和杯植入过程中产生的压力，这两个髋臼杯除了一个带有法兰外，其余完全相同。结果发现，带边髋臼部件并没有显著增加髋臼内的压力，在某些情况下，与不带边的髋臼杯相比，压力反而降低。法兰的增加并没有降低髋臼杯内极和边缘之间的压力差，也没有对杯植入过程中的压力损失产生显著影响。因此得出结论，带边髋臼杯在髋臼杯植入过程中对髋臼内产生的压力没有显著改善。可以假设，法兰可能被视为一种设计特征，旨在减缓髋臼杯插入水泥的速度，因此需要外科医生施加更大的负载才能正确定位髋臼杯；这样会产生更大的压力。
