Wear Mechanics in Joint Replacement

Types of Wears

Mode I - Joint Articulation

Mode II - Primary Articular surface non intended to be a bearing surface (femoral head and metal

                 cup in acetabulum )

Mode III - Articulating surface and debris


Mode IV - One non weight bearing surface (polyethylene insert and a tibial tray )



Mechanism

Adhesion - repeated multiaxial loading leading to cracks.

Abrasion- hard and soft material objects in contact and motion.

Third body wear

Fatigue

Corrosion












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