Bone treatment systems and methods

A method for treating a bone, comprising:

• flowing bone fill material through a bone fill material injector system having at least a portion of an injector positioned in a cancellous bone portion of the bone;
• delivering a first non-zero level of applied energy to the flow of bone fill material via a thermal energy emitter in communication with the bone fill material injector system, wherein delivering the first non-zero level of applied energy changes the viscosity of the bone fill material to a first viscosity;
• delivering a second non-zero level of applied energy to the flow of bone fill material via the thermal energy emitter after delivering the first non-zero level of applied energy, wherein delivering the second non-zero level of applied energy changes the viscosity of the bone fill material to a second viscosity less than the first viscosity, the first and second viscosities defining a viscosity range therebetween;
• delivering a third non-zero level of applied energy to the flow of bone fill material via the thermal energy emitter after delivering the second non-zero level of applied energy, wherein delivering the third non-zero level of applied energy changes the viscosity of the bone fill material to the first viscosity;
• wherein the third non-zero level of applied energy is less than the first non-zero level of applied energy;
• and
• electronically controlling the delivery of the first, second, and third non-zero levels of energy via the thermal energy emitter to modulate the viscosity of the bone fill material about a desired mean bone fill material viscosity within the viscosity range based at least in part on a sensed parameter of the bone fill material injector system.