Ceramic on metal hips... ......................may be the best hip ever! ...................................Orthopedics Today, Volume 27-Number 8, August 2007
	Early clinical studies are showing that ceramic on metal (COM) hip bearings are showing markedly lower wear compared to metal on metal (MOM) hip bearings. Researchers have done both clinical and laboratory studies comparing COM and MOM measurements of friction wear and have shown a lower friction with COM. To compare the MOM and the COM and ceramic on ceramic (COC) researchers performed hip simulations of 3 million cycles under standard conditions and found that COM and COC combinations showed no initial bedding inwear, unlike the MOM couples. In other tests metal-ion levels were tested at various stages and low levels of cobalt, chromion and molybdenum ions were found in the COM bearing compared with the MOM bearings. The bottom line of these studies was that COM bearings provided less wear, fewer metal ions which can potentially lead to years increase in long term success.