Effect of Radial Clearance on Wear and Contact Pressure of Hard-on-Hard Hip Prostheses Using Finite Element Concepts

Abstract

Wear of the bearing surface increases the revision rate of artificial hip replacements and is influenced by the radial clearances between the acetabulum cup and the femoral head. The objective of this article is to determine the effect of various radial clearance values over the contact pressure and wear of the hard-on-hard—that is, polycrystalline diamond (PCD)—hip prostheses using finite element concepts for normal walking conditions. The wear of the hip bearing surface is determined by considering the contact pressures obtained from the hip gait instants of normal walking activity and sliding distance determined from the three-dimensional hip gait motions. The radial clearance value of 0.05 mm showed less volumetric wear rate when compared with other radial clearance values. Overall, it is recommended that the low radial clearance between the contacting pair is suitable for PCD-on-PCD hip prostheses.