MacBook Pro 13" 2011 NEEDS REPAIR?

HELLO, I was given a macbook pro 13" early 2011 that was sadly thrown down cement steps. It turned on, fan ran. clicking hard drive and no screen turned on. I put in a new hd that I had down loaded mountain lion, hooked it to a external monitor and it is running sweet. I can get on internet and watch movies and more. The keyboard and tract pad is not working so I have a blue tooth keyboard or a usb keyboard that I use. and the screen which is in excellent cosmetic condition is not working. How would I find out if I need a logic board. I was going to replace the tract board, and the keyboard and get a screen assembly. But the logic board is pretty expensive. So my question is how do I find out if the logic board would need replacement and is it worth fixing it.

Thank you

Lynn Heiser

macbook pro 17"