Remove the stems from the mushrooms and clean the caps with a damp paper towel. Arrange the mushroom caps on a parchment-lined baking sheet.
In a medium bowl, mix the cream cheese, garlic, Worcestershire sauce, green onion, breadcrumbs, and half of the Parmesan cheese. Fold in the crab meat.
Spoon the crab mixture into the mushroom caps. Sprinkle with the remaining Parmesan and chopped parsley.
Bake for 20-25 minutes, until the mushrooms are tender and the filling is hot and starting to brown on top.