How can I get items from a loot table to *drop* on a trigger?

So basically, I have an item that, when right clicked, I want to drop an item from a loot table in front of the player. I know the spawn item command, and I have a loot table, but how can I link the two? I don't know if there's a 'loot table data block' or something I can plug into the gem. Thanks!