This study is being done to investigate the colonization rate(growth rate) of a particular type of low-virulence (does not typically cause infection) bacterium called Propionibacterium. The most common bacterium of this family is P acnes, the same bacterium that is responsible for the majority of acne. There is increasing evidence that infection with P acnes and other Propionibacterium is a significant source of failure following certain orthopaedic shoulder procedures. However, information affecting hip surgery is currently unknown. Our personal experience leads us to believe that the numbers are actually quite high, since we are seeing an increased rate of Propionibacterium infection of hip replacement in the community. However, this type of study has never been done before, and therefore we simply do not know an accurate estimate for the average hip replacement patient's risk for Propionibacterium infection following hip replacement.
