What Causes Pain In Thighs Radiating To Shin And Foot?

i have pain in right leg , front leg, from quad to shin to foot, what causes such? I've had sciatica before but it was always at back of leg and butt. it aches constantly and is at its worse when i try to sleep. it hurts when i sleep on each side. no relief with pillows as wedges. aches while on back also.