Here’s an awesome tool that many pro athletes use these days. Our clients are amazed at what 2 minutes feels like after. For a knee or ankle that’s giving you trouble, this brings immediate relief and long-term benefits.
Grab a butter knife, use the blunt end, and it should feel like you’re scratching a deep itch. If you end up with tiny red dots, broken blood vessels called petechiae, that means you went too hard. 
Skaters get so many shinners and impacts on the inside of the knee and ankle, there’s scar tissue everywhere. 30 seconds in one spot, then move to another.