In the following video, Fool contributor Matt Thalman discuss how the robotic surgery industry is changing in front of investors' eyes. MAKO Surgical (MAKO.DL) and Intuitive Surgical (ISRG -0.45%) are the two big players in this market and have seen their share prices fall in the past few months as sales have slowed down. At least for Intuitive Surgical, this comes at a time when the company is attempting to transition from relying on selling razors to selling more blades, with demand from hospitals slowing down as many can't justify spending the money on the da Vinci machine today.

As we've seen with other industries, selling the razor is great, but over the course of years and years, the real money comes from selling the blades.

Check out the video for more information.