The John Charnley Award. Practice surveillance: a practical method to assess outcome and to perform clinical research.

The senior author systematically began collecting preoperative and postoperative data on all the total hip arthroplasties he performed starting in July 1970. The data collected represent a 26-year experience using practice surveillance (preoperative and regular interval postoperative collection and analysis of outcomes) as a method to document the outcome of the total hip arthroplasty procedure and as a method to evaluate the need for changes in the procedure. As the senior author made few selected changes in the operative procedure during the followup period, the primary author has been able to evaluate the change in outcome based on these changes. The six studies reported in the current study show the durability of the long-term results of cemented total hip arthroplasty, the improvement in radiographic reproducibility obtained on the femoral side of the construct with improved cementing techniques, the deleterious effects of using cable to reattach the greater trochanter, the deleterious effects of changing femoral component design that included a change in surface finish, the improvement in acetabular fixation using cementless fixation, and the optimization of bearing surface wear using smaller diameter femoral heads. All of these findings have been incorporated into the primary surgeon's practice based on this practice surveillance. As shown, practice surveillance also has provided a tool for performing clinical research. Although practice surveillance of controlled cohorts never will supplant prospective randomized clinical trials in evidence based medicine, it should help each surgeon with his or her own practice and can be used as an important research tool to study the optimization of outcomes of a surgical procedure.