Wear simulation is one of the many services available to you for investigating bearing surfaces and prosthetic designs. In vitro wear simulators approximate in vivo conditions, allowing performance evaluation of new designs and bearing materials prior to large-scale manufacture and implantation.
What equipment do you use for testing?
We perform all of our knee simulator wear tests using the six-station AMTI knee simulator developed and manufactured by Advanced Mechanical Technology Inc. (AMTI), which can replicate activities of daily living such as running, deep knee bends, and stair climbing. The simulator can be operated under both force and displacement control, and is capable of testing to ISO and ASTM standards, ensuring consistent, repeatable procedures and results.
What are the equipment specifications?
Parameter Specification Test Stations 6 Load Soak Stations 4 Axial Load 4500N (1000lb) Degrees of Freedom Flexion ±100° @ 20Nm (180in-lb) IE Rotation ±20° @ 8Nm (70in-lb) AP Translation ±25mm ML Translation ±6mm Valgus Rotation ±7° Multi-axial Load Cell Axial Load 4500N AP Force 4000N ML Force 4000N Flexion Moment 25Nm Abduction Moment 25Nm Axial Moment 25Nm
Why is this type of testing important?
Joint simulator wear testing allows researchers, manufacturers, and industry professionals to evaluate the wear performance of their prosthesis design and bearing materials under physiological conditions. These tests can help our clients optimize and improve their designs prior to large-scale manufacturing and implantation, in addition to meeting regulatory requirements.
Can tests be performed under physiological conditions?
The OIC specializes in testing under physiological conditions, especially in the type of lubricant used to mimic synovial fluid. Please refer to our publications to learn more about our innovative research in this area.
In addition, AMTI’s new Virtual Soft Tissue (VST) control uses an advanced software model to mimic the constraining influence of soft tissue surrounding the knee to more fully replicate the natural physical environment. Every station is paired with a peristaltic pump that recirculates a temperature-controlled bath surrounding the contact area of the specimen.
Standards We Test
Practice for Gravimetric Measurement of Polymeric Components for Wear Assessment
Implants for surgery — Wear of total knee-joint prostheses