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The advantages of all-alumina bearings are superb wear resistance, stability, and inertness demonstrated over 3 decades. The disadvantage is a small risk for brittle fracture, as described in this paper. Surveying the latest ceramic hip series reported in recent journal articles or presented at the 6th World Biomaterials Congress, we found 11 studies representing more than 35,000 cases followed for 3 to 25 years. There were 24 reported fractures. A unique survey of hip complications in the 1990s found a fracture risk of approximately 1.4 per 1000 ceramic balls used in the United States. A company database holding more than 2.5 million records described the overall fracture risk as 1 per 10,000 cases. Initial use of ceramic cup inserts indicated a 2% to 3% incidence of chipping during surgery. Beginning in 1997, the number of ceramic-metal cup-locking cases entered into a US Food and Drug Administration ceramics database was more than 2400, with no fractures reported by the FDA in July 2003.

Polyethylene wear and extension of indications of total hip arthroplasty into younger and younger age groups have pushed manufacturers to develop more durable bearing surfaces. Standard polyethylene, the plastic used for the first 3 decades of hip replacement, virtually ceases to exist in its original form. Modifications of the processing, including sterlization in an inert environment and cross-linking, have demonstrated some improvements in wear. Hard-on-hard bearings such as ceramic-on-ceramic and metal-on-metal also have demonstrated extremely low wear. This article reviews the pros and cons of the alternative bearing options available to assist in the proper bearing selection for a particular patient.