Sanders, A. P., and R. M. Brannon. (2010) “Hertzian contact theory applied to edge-loaded ceramic-on-ceramic hip bearings: analysis and validation.” Transaction of the 56th Annual Meeting of the Orthopaedic Research Society, March 6-9, New Orleans, LA, Poster 2258.
This work addresses the problem of wear of ceramic-on-ceramic bearing couples used in total hip arthroplasty. A wear pattern called stripe wear has been observed on retrieved ceramic femoral heads. It typically appears as a long, narrow, roughened area on affected implants. Evaluation of the wear stripe has revealed grain removal and material loss to depths of 30 mm. It has been theorized that such damage is caused by contact between the femoral head and the edge of the acetabular cup. An edge-loaded contact is much less congruent than normal contact, and it would cause increased contact stress, leading to the wear stripe. Edge-loading may be due to small separations of the head from the cup, as observed radiographically. Simulator wear tests involving such separation have yielded wear stripes similar to those on retrieved bearings.