Apparatus and methods for removal of intervertebral disc tissues

A method of removing tissue from an intervertebral space comprising:

• providing an apparatus for removing tissue from an intervertebral disc comprising an elongated guide tube defining a lumen extending through the elongated guide tube from a proximal opening at a proximal end of the elongated guide tube to a distal opening at a distal end of the elongated guide tube, the lumen including a bendable portion providing a bendable end near the distal end, the guide tube having a wall having a first bend control lumen therein and a second bend control lumen therein;
• a first control wire within the first bend control lumen;
• a second control wire within the second bend control lumen;
• an actuator for moving at least one of the first control wire or the second control wire;
• a cutting head housing slidably received within the distal opening at the distal end of the elongated guide tube, the cutting head housing positionable between a first retracted position and a second extended position relative to the distal end of the elongated guide tube;
• a cutting member positioned within the cutting head housing, the cutting member adapted to rotate with respect to the cutting head;
• a drive shaft rotatably received within the lumen and extending between the proximal opening in the guide tube and attached to the rotary cutting member;
• a driver attached to the drive shaft near the proximal opening in the guide tube;
• the cutting head housing including a blunt end and having a cutting opening therein, the cutting opening including a cutting edge located between the blunt end and the distal end of the guide tube;
• and
• a control apparatus attached near the distal opening of the elongated guide, the control apparatus including a wire controller attached to the first control wire and the second control wire, the wire controller for varying the length of the first control wire and the second control wire to selectively bend the bendable end, the control apparatus further comprises an extension mechanism for selectively extending the cutting head housing with respect to the distal end of the guide tube;
• positioning the bendable end of the elongated guide tube within an intervertebral disc space with the blunt end and a portion of the cutting head housing near an annulus of a disc;
• rotating the cutting member within the cutting head housing while bending the bendable end;
• controllably bending the bendable end away from the annulus of the disc, thereby imparting a sweeping motion within the intervertebral space with the cutting head housing in a first retracted position relative to the bendable end of the elongated guide tube to cut a nucleus pulposus of the interverbral disc;
• extending the cutting head housing from the first retracted position to the second extended position relative to the bendable end of the elongated guide tube:
• and
• controllably bending the bendable end away from the annulus of the disc, thereby imparting a sweeping motion within the intervertebral space with the cutting head housing in a second extended position relative to the bendable end of the elongated guide tube to cut the nucleus pulposus of the interverbral disc.

An apparatus for removing tissue from an intervertebral disc comprising:

• an elongated guide tube defining a lumen extending through the elongated guide tube from a proximal opening at a proximal end of the elongated guide tube to a distal opening at a distal end of the elongated guide tube, the lumen including a bendable portion providing a bendable end near the distal end, the guide tube having a wall having a first bend control lumen therein and a second bend control lumen therein;
• a first control wire within the first bend control lumen;
• a second control wire within the second bend control lumen;
• an actuator for moving at least one of the first control wire or the second control wire;
• a cutting head housing slidably received within the distal opening at the distal end of the elongated guide tube, the cutting head housing positionable between a first retracted position and a second extended position relative to the distal end of the elongated guide tube;
• a cutting member positioned within the cutting head housing, the cutting member adapted to rotate with respect to the cutting head;
• a drive shaft rotatably received within the lumen and extending between the proximal opening in the guide tube and attached to the rotary cutting member;
• and
• a driver attached to the drive shaft near the proximal opening in the guide tube;
• the cutting head housing including a blunt end and having a cutting opening therein, the cutting opening including a cutting edge located between the blunt end and the distal end of the guide tube;
• a control apparatus attached near the distal opening of the elongated guide, the control apparatus including a wire controller attached to the first control wire and the second control wire, the wire controller for varying the length of the first control wire and the second control wire to selectively bend the bendable end, the control apparatus further comprises an extension mechanism for selectively extending the cutting head housing with respect to the distal end of the guide tube;
• the cutting member and cutting head housing each defining an opening on a side of the cutting member and a side of the cutting head that does not extend beyond a central axis of the cutting member and the cutting head housing, such that each opening is aligned during a portion of a rotation of the cutting member about the central axis to provide a passage between the outside of the cutting head housing and the inside of the cutting member;
• a fluid passage directed into the inside of the cutting member, the fluid passage in fluid communication with a source of irrigation fluid;
• and
• a vacuum source attached to the proximal end of the lumen of the elongated guide tube, the vacuum source producing a vacuum at the distal end of the lumen and at the opening in the cutting head housing.

A method of removal of tissue from an intervertebral disc comprising:

• providing an apparatus for removing tissue from an intervertebral disc comprising an elongated guide tube defining a lumen extending through the elongated guide tube from a proximal opening at a proximal end of the elongated guide tube to a distal opening at a distal end of the elongated guide tube, the lumen including a bendable portion providing a bendable end near the distal end, the guide tube having a wall having a first bend control lumen therein and a second bend control lumen therein;
• a first control wire within the first bend control lumen;
• a second control wire within the second bend control lumen;
• an actuator for moving at least one of the first control wire or the second control wire;
• a cutting head housing slidably received within the distal opening at the distal end of the elongated guide tube, the cutting head housing positionable between a first retracted position and a second extended position relative to the distal end of the elongated guide tube;
• a cutting member positioned within the cutting head housing, the cutting member adapted to rotate with respect to the cutting head;
• a drive shaft rotatably received within the lumen and extending between the proximal opening in the guide tube and attached to the rotary cutting member;
• a driver attached to the drive shaft near the proximal opening in the guide tube;
• the cutting head housing including a blunt end and having a cutting opening therein, the cutting opening including a cutting edge located between the blunt end and the distal end of the guide tube;
• and
• a control apparatus attached near the distal opening of the elongated guide, the control apparatus including a wire controller attached to the first control wire and the second control wire, the wire controller for varying the length of the first control wire and the second control wire to selectively bend the bendable end, the control apparatus further comprises an extension mechanism for selectively extending the cutting head housing with respect to the distal end of the guide tube;
• positioning the cutting head housing within the intervertebral disc space;
• rotating the cutting member to cut nucleus pulposus tissue from within the disc space;
• pumping irrigation fluid through a fluid passage directed into the inside of the cutting member;
• producing a vacuum at the end of the proximal end of the lumen of the elongated tube to remove the cut material and irrigation fluid through the lumen of the elongated tube;
• and
• selecting the cutting member rotational speed, irrigation fluid flow rate, and amount of vacuum such that these parameter levels, in combination with the size of the openings in the cutting member and cutting head, to preferentially cut and remove nucleus pulposus tissue over surrounding annulus fibrosus and cartilage tissue.