In the following video, David Williamson highlights three health-care stocks that had huge -- 25% or more -- moves. Both MAKO Surgical and Dendreon took a tumble on earnings, while Arena soared ahead of an FDA advisory panel. For a closer look at these companies and what investors should make of the market’s reaction, watch the video and Fool on.

David Williamson owns shares of Dendreon and Johnson & Johnson, but he holds no other position in any company mentioned. Check out his holdings and a short bio. The Motley Fool owns shares of MAKO Surgical, Intuitive Surgical, Dendreon, and Johnson & Johnson. Motley Fool newsletter services have recommended buying shares of Johnson & Johnson, MAKO Surgical, and Intuitive Surgical and creating a diagonal call position in Johnson & Johnson. The Motley Fool has a disclosure policy. We Fools don't all hold the same opinions, but we all believe that considering a diverse range of insights makes us better investors. Try any of our Foolish newsletter services free for 30 days.