US Patent 8128619 Method for treating intervertebral discs

A method of treating an intervertebral disc includes inserting an introducer into an intervertebral disc, inserting a catheter through the introducer and into the intervertebral disc, advancing a distal region of the catheter through a nucleus pulposus of the intervertebral disc to an annular wall of an annulus fibrosus, delivering energy to material of the intervertebral disc using an electrode disposed at the distal region of the catheter, and removing the material with the delivered energy, wherein removing material with the delivered energy reduces pressure in the intervertebral disc.