Common Causes of THR Revisions in the US 2005-2006Updated 10/27/09 Read Complete Article by clicking hereInterview of Kevin J. Bozic, MD, MBA by Douglas W. Jackson, MDAccording to the Nationwide Inpatient Sample (NIS) database, which is a stratified, statistically valid survey of inpatient hospital visits in the United States, there are almost 40,000 revision total hip arthroplasties (THAs) performed annually in the United States. This number has steadily increased over the past 20 years, and is expected to continue to increase over the next several decades. This increase is primarily due to an increased incidence of primary THA procedures, an expansion of the indications for THA to include younger, more active patients, and limitations in implant longevity……Between October 2005 and December 2006, the most common causes of revision THA in the United States (see chart) were hip instability (22.5%), mechanical loosening (19.7%) and infection (14.8%). T