How to unlock iPhone 4 with computer? Is there a way?

Long story short, I replaced my screen on my iPhone 4. The ribbon cable that allows you to see the screen is connected and therefore I can see my screen, but the ribbon cable that allows for touch is too short to be connected and I have no way to do anything on my phone.
All I'm trying to do is unlock my phone so I can back it up on my computer. The problem is, a phone has to first be unlocked in order to back it up through iTunes. I can't unlock my phone because the touch screen is not working.
Does anyone know if there's a way to unlock an iPhone 4 with your computer?

Take the phone to someone who knows what he/she is doing.