Is There Anything to Learn from a National Joint Registry?

National joint registries (NJRs) have been established in Northern Europe for over 20 years. Since then, many other countries have begun collecting and reporting national data for total ankle arthroplasty (TAA). With relatively small numbers implanted, a large variety of available designs, and with any long-term reports dominated by designer groups, TAA is ideally placed to benefit from large national or even pooled national registries. This article reviews the existing registry-based literature with respect to what is already known. The potential positives and down sides of registry data also are highlighted.