A method of delivering energy to an intervertebral disc includes positioning an energy delivery device adjacent an inner wall of the disc, and shrinking the nucleus pulposus. An energy delivery element of the device is positioned adjacent a bulge in the intervertebral disc. Energy delivery is controlled based on monitored temperature. A device for delivering energy includes a catheter with a distal portion configured to be inserted into a patient and to follow a natural boundary of a patient tissue, and an energy delivery element located at the distal portion for treating tissue. The distal portion includes a braided polymeric material. The catheter has a proximal portion including a tube for transmitted torque to the distal portion. The energy delivery element is a resistive heating coil having a length, e.g., of about 1.5 cm.