Patent attributes
A surgical instrument comprises a hollow tube (18) having a cutting window (16) at the distal end portion. An inner tube (15) is disposed within the tube (18) and is mounted for rotation about its longitudinal axis. A cutting tool (17) is located at the distal end of the tube (15), and is positioned adjacent to the cutting window (16). An outer tube (14) is provided over the tube (18). A motor (5) is provided for rotating the inner tube (15), and saline is fed to the cutting window (16) via a passageway (25) between the tubes (15) and (18). The inner tube (15) has a central lumen (24) through which tissue cut by the cutting tool (17) is removed under the action of a source of suction (12). The outer surface of the tube (18) is covered with an electrically insulating layer (22) and coagulating RF signals are supplied between the tube (18) and the outer tube (14) so as to coagulate tissue at the cutting window (16). A weakened portion (43) of the outer tube (14) ensures that when the outer tube (14) and hollow tube (18) are bent to form a curved portion (42), the relative positioning of the respective distal ends of the tubes (14) and (18) is maintained.
