The present invention relates in certain embodiments to methods, systems, and devices for treating vertebral compression fractures. In one embodiment, a bone cement injector is advanced into bone and injects a bone cement flow through the injector and a vapor flow from at least one vapor outlet in the injector. In another embodiment, the bone treatment system comprises an elongated member having a flow passageway, a bone fill material source, and a vapor source coupleable to the flow passageway. Still another embodiment describes a vapor injection device having an elongated member with a flow passageway, the elongated member configured for insertion into a bone and for delivering a bone fill material through the flow passageway, and having at least one vapor channel in communication with the flow passageway to deliver a vapor into the flow passageway to heat a bone fill material flow.