Arthroscopic shaver

Claim 2

A surgical instrument for cutting tissue, the instrument comprising: an outer tube sized and shaped for insertion through a puncture in the flesh of a body, the outer tube having a side-facing opening therein for the entrance of tissue to be cut; an inner tube fitted in the outer tube and adapted to rotate relative to the outer tube, the inner tube including a side-facing opening defining a blade adapted to co-act in cutting action with a cooperating edge of the side-facing opening of the outer tube; the inner tube further including a longitudinal opening on its proximal end adapted for connection to a suction device for drawing fluid and cuttings into the openings and for drawing the fluid and cuttings through the instrument; means for connecting the inner tube to a drive motor for continuously rotating the inner tube relative to the outer tube so that the blade on the inner tube is moved past the cooperating edge of the side-facing opening in the outer tube; bearing means at the distal end of the inner and outer tubes for supporting and aligning the inner tube relative to the outer tube; the bearing means including a first bearing surface projecting into the outer tube and forming an annular space that tapers inwardly away from the inner side surface of the outer tube; and a second bearing surface at the distal end of the inner tube shaped and dimensioned to overlap and cooperate with the first bearing surface and extend around substantially the entire distal end of the inner tube.

Claim 3

The improvement of claim 1, wherein: the first bearing surface is formed on the outer conical surface of a truncated cone projecting into the distal end of the outer tube; and the second bearing surface is beveled to overlap and cooperate with the outer conical surface of the first bearing surface.

Claim 4

The improvement of claim 1, wherein: the outer tube is swaged to fit closely over the inner tube; and the outer side surface of the inner tube is polished to a smooth finish.

Claim 5

The improvement of claim 1, wherein: the outer tube is open at the distal end and the first bearing surface is formed on a plug connected to the distal end of the outer tube.

Claim 6

The improvement of claim 1, wherein the side-facing openings in the inner and outer tubes are oval in shape.

Claim 7

The improvement of claim 5, wherein the opening of the outer tube is formed entirely above the axial centerline of the tube and a rim surface defining the opening is substantially perpendicular to the inner side surface of the outer tube.

Claim 8

The improvement of claim 6, wherein the blade edge of the opening of the inner tube is coincidental with the cooperating edge of the rim surface in the outer tube, and the blade defining the opening of the inner tube is beveled.

Claim 9

A surgical instrument for cutting tissue, the instrument comprising: an outer tube sized and shaped for insertion through a puncture in the flesh of a body, the outer tube having a side-facing opening therein for the entrance of tissue to be cut; an inner tube fitted in the outer tube and adapted to rotate relative to the outer tube, the inner tube including a side-facing opening defining a blade adapted to co-act in cutting action with a cooperating edge of the side-facing opening of the outer tube; the inner tube further including a longitudinal opening on its proximal end adapted for connection to a suction device for drawing fluid and cuttings into the openings and for drawing the fluid and cuttings through the instrument; means for connecting the inner tube to a drive motor for continuously rotating the inner tube relative to the outer tube so that the blade on the inner tube is moved past the cooperating edge of the side-facing opening in the outer tube; the outer tube having a distal end portion, the outer tube opening being generally elliptical and located within the distal end portion; the inner tube having a distal end portion, the inner tube opening being generally elliptical and located within the distal end portion, the outer surface of the inner tub defining said inner tube opening being the same size and shape as the inner surface of the outer tube defining said outer tube opening for forming cooperating cutting surfaces for cutting tissue when the inner tube rotates relative to the outer tube.

Claim 10

A surgical instrument for cutting tissue, the instrument comprising: an outer tube sized and shaped for insertion through a puncture in the flesh of a body, the outer tube having a side-facing opening therein for the entrance of tissue to be cut; an inner tube fitted in the outer tube and adapted to rotate relative to the outer tube, the inner tube including a side-facing opening defining a blade adapted to co-act in cutting action with a cooperating edge of the side-facing opening of the outer tube; the inner tube further including a longitudinal opening on its proximal end adapted for connection to a suction device for drawing fluid and cuttings into the openings and for drawing the fluid and cuttings through the instrument; means for connecting the inner tube to a drive motor for continuously rotating the inner tube relative to the outer tube so that the blade on the inner tube is moved past the cooperating edge of the side-facing opening in the outer tube; the outer tube having a distal end portion, the outer tube opening being generally elliptical and located within the distal end portion; the inner tube having a distal end portion, the inner tube opening being generally elliptical and located within the distal end portion, the outer surface of the inner tub defining said inner tube opening being the same size and shape as the inner surface of the outer tube defining said outer tube opening for forming cooperating cutting surfaces for cutting tissue when the inner tube rotates relative to the outer tube.

Claim 11

The improvement of claim 8, wherein the inner tube opening is beveled for forming a sharp cutting edge around the outer surface of the inner tube, which defines said inner tube opening.

Claim 12

The improvement of claim 8, and further including bearing means at the distal end of the inner and outer tubes for supporting and aligning the inner tube relative to the outer tube, the bearing means including a first bearing surface projecting into the outer tube and forming an annular space between the first bearing surface and the inner side surface of the outer tube, and a second bearing surface at the distal end of the inner tube adapted to overlap and cooperate with the first bearing surface.