Does elevated alkaline phosphatase cause bone pain?

No: Alkaline phosphatase is known as a "marker" of increased bone (or liver) metabolism. It is contained in bone (and liver) so it will be elevated when bone is being broken down or resorbed as in paget's disease or bone cancer. It doesn't cause bone pain per se, but whatever is causing the bone to break down in the first place (e.g. Paget's disease or bone cancer) is the cause of the pain.