LARGE CERAMIC HEADS: WHAT PROBLEMS DO THEY SOLVE?

Abstract

1. 1.

   Do large heads result in better stability in practice?

   1. –

      Prospective Randomized Studies showing increased stability

2. 2.

   How much of a risk is ceramic head fracture with current generation materials?

   1. –

      Minimal (0.004%)

3. 3.

   How much of an actual risk is liner fracture with thin polyethylene liners?

   1. –

      Minimal (only in isolated case reports with component malposition/impingement)

4. 4.

   What wear advantage is gained by using ceramic over metal heads?

   1. –

      Simulator studies (clear advantage)

   2. –

      Clinical studies – Small difference in linear wear rate (with Zirconia)

   3. –

      Larger difference in wear rate with newer materials (BIOLOX)

5. 5.

   What other advantage is gained by using ceramic heads over metal heads?

   1. –

      No CoCr in system – less corrosion

   2. –

      Corrosion at head-neck junction can be a big problem – pseudotumours

   3. –

      Meftah/Rodriguez COP

   4. –

      Ceramic heads cause less fretting and corrosion than metal heads in in vitro study