Methods, systems, and devices are disclosed for cooling tissue, and in particular for applying therapeutic hypothermia to the spinal canal, tissue disposed within the spinal canal, and nerve roots extending from the spinal canal. Bone screws, intervertebral implants, stabilization rods, spinous process spacers, and other devices are described which define a chamber through which a chilled fluid, expandable gas, or other coolant means can be circulated, delivered, or activated to cool adjacent tissue. The degree of cooling can be regulated using a controller, which can be configured to increase or decrease the cooling effect based on any of a variety of measured or predicted physiological or thermodynamic properties. Methods are disclosed for implanting cooling instruments and for carrying out various treatment regimens that involve cooling tissue using such instruments.