An electrosurgical probe for ablating tissue includes an elongated shaft having an axis and a distal end. An electrically insulating housing at the distal end of the shaft has a window, and an interior channel in the shaft extends through the housing to the window. The window faces laterally relative to the axis, and a moveable member with a blade-like electrode edge is disposed within the window. A motor drives the energized electrode edge axially in the window to ablate tissue.
