What defines a high-volume hip or knee surgeon in the United States?

The literature suggests that high-volume hip and knee surgeons have better patient outcomes. Therefore, clearly defining a high-volume or a low-volume surgeon is important. The definition of high-volume has been quite arbitrary, and numbers such as 50 surgeries per year have been used to define high-volume. The objective of this study was to show that, on the basis of data contained in the National Inpatient Sample database, using the quartile approach will quantify the increasing number of surgeries required per year to remain a high-volume joint surgeon. Using quartiles may provide a more consistent way to define what is meant by a low- or high-volume surgeon in the United States, and a clear definition of quartiles will aid future studies seeking to determine whether outcomes can be correlated with quartiles.