Does the use of polyethylene as an interface material not increase the risk of micro-motion and resultant PE wear?
This design is based on several years of experience with the stepped taper connection between polyethylene inserts and cup shells. The elasticity of the titanium shell and the polyethylene, combined with the tapered design of the individual components, means that they interlock in such a way that micro-motion between them is avoided. If a tapered connection has worked loose it can be rendered stabile, whereas a snap connection cannot. The connection between the retaining body and polyethylene differs between the ceramic and metal constructions. A form-fit snap connection lug is attached to the ceramic body in addition to the single taper. The metal body on the other hand is connected to the polyethylene via a stepped taper. Plus Orthopedics has chosen the mode of connection that offers the highest degree of safety.
