I find that their idea of low carb almost always varies from mine. It works better to just go a la carte, and put together your own dish by ordering some meat, and clearing everything off your plate but vegetables. I usually get them to give me a double helping of veggies, instead of rice/potatoes. Also ask about sauces, and make sure there is none. They have sugar probably.
Whenever I eat a " low carb " selection at a restaurant I stall, but putting together my own plate usually is not a problem. Almost every restaurant has meat or fish, and vegetables, so you can eat at them all, if you do it this way.