This interactive D3.js visualization displays a hierarchical tree of hip replacement specialists, organized by country, city, institution, and expert name, based on CSV data fetched from a GitHub gist. The tree uses a horizontal tidy layout with collapsible nodes, rendered as SVG with animated transitions. The page features a dark blue background, displays a header image, and leverages D3 v7’s `d3.hierarchy` and `d3.tree` APIs along with `d3.linkHorizontal` for the curved connecting links.