The development of simulator testing for total knee replacements

Abstract

Professor Duncan Dowson was a pioneer in the field of tribology and simulator design. His work sparked many branches of research across orthopaedics. The first knee simulator described by Dowson was intended to measure the wear performance of early total knee replacements (TKRs). The industry has since advanced to achieve simulator designs with significant improvements including multi-station, multi-axis, multi-control, and multi-environmental capabilities. These simulators are used to test and compare not only wear, but also the kinematic/kinetic behaviour of TKRs and many other TKR design interactions prior to implantation. This has led to changes to the design of TKRs ranging from improvements to the tibial insert to the femoral component; all, in some way, thanks to Professor Duncan Dowson's inquisitive nature. This article provides a selective review to show the interdependencies of research and development endeavours starting with the evolution of knee simulators, the many advances in TKRs and finally the interconnection with cadaveric motion simulators.This is an open access article under the terms of the Creative Commons Attribution-NoDerivs License, which permits use and distribution in any medium, provided the original work is properly cited and no modifications or adaptations are made.

Revisión de los sistemas de control aplicados a los simuladores de rodilla

“…Este tipo de mecanismo se ha convertido en uno de los más usados para pruebas de prótesis, por lo que los modelos existentes han sido comercializados y no hay información científica detallada de los mismos. Se pueden encontrar trabajos de los modelos existentes más utilizados, donde se resumen las principales características de rango de carga y desplazamiento, así como de las condiciones de prueba en cuanto a velocidad, temperatura y lubricación (42). En otros casos, las fuentes de información principales son las patentes, páginas de internet y hojas de especificaciones de los fabricantes.…”

“…Considerando que estos simuladores trabajan bajo una norma, y que esta depende de la variable controlada, se han estudiado las ventajas y desventajas del uso de la norma ISO 14243 para el control de fuerza (71) y el control de desplazamiento (72). Se recomienda utilizar el modo de control de fuerza para los diseños altamente congruentes, constreñidos y con pivote medial, mientras que el modo de control del desplazamiento podría utilizarse para los diseños poco congruentes, poco constreñidos interna o externamente y placas tibiales planas (42). La Tabla III presenta una comparación de la norma ISO 14243-1 para el control de fuerza y la ISO 14243-3 para el control de desplazamiento, donde se observa que la elección de la norma adecuada para el simulador puede ser determinante en el tipo de prótesis diseñada y las pruebas deseadas.…”

A Sensorized 3d-Printed Knee Test Rig for Experimental Validation of Patellar Tracking and Contact Simulation After Total Knee Replacement

“…On the other hand, knee simulators have revolutionized the way researchers, surgeons, and manufacturers approach implant design, durability assessment, surgical techniques, and patient safety, by providing a controlled and repeatable environment for evaluating TKR implants. While the first knee simulator described by Dowson in 1977 was a mechanical device, later, cadaveric knee simulators have emerged as a response to the need for gaining deeper insights into the workings of both the native knee and TKRs (Maag et al 2021). The underlying concept involves the integration of implants into these cadaveric simulators, with the goal of prescribing specific muscle forces and displacements within the simulator.…”

Shape Memory Alloys Patches to Mimic Rolling, Sliding, and Spinning Movements of the Knee

“…Maag et al's paper developed a robot knee joint simulator to assess the wear and damage of artificial joints. This simulator was designed to mimic the actual movement of the knee joint, enabling the evaluation of artificial joint performance under various conditions [12]. Bates et al's paper simulated cadaveric knee walking, focusing on the role of the anterior cruciate ligament (ACL) inside the knee joint during movement.…”