Can knee bursitis side vein impingement leaving a foot slightly blue?

Foot blue: Knee bursitis, which doesn't impinge leg veins, should not be a cause of bluish discoloration of the foot. Is the foot bluish when it's in a dependent position and also when when the leg is elevated and is it different from the other foot? If so, leg vein obstruction or phlebitis may be present. ?both feet same. Have a physician examine you for peace of mind if only one foot has the discoloration