TIGHTENING DEVICE FOR SPINE SURGERY
A device for spinal surgery that may be used for tightening a locking cap onto at least a portion of a pedicle screw. The device may include a torque-generating body having a proximal end and an opposing distal end and a drive shaft rotatably driven by the torque-generating body. A proximal end of the drive shaft may be operatively engaged to the distal end of the torque-generating body and an opposing distal end of the drive shaft may engage at least a portion of one of the locking cap and the pedicle screw. An anti-torque device is provided that has an elongated and generally hollow member defining a longitudinal axis. The member has a proximal end and an opposing distal end, where the proximal end of the anti-torque device may be fixed from rotating relative to at least a portion of the torque-generating body and the distal end may be fixed from rotating relative to a spine rod or a pedicle screw.
1 . A surgical device for use during spinal surgery, the device comprising:
a torque-generating body having a proximal end and an opposing distal end and defining a longitudinal axis extending therebetween, the distal end coupled to a handle;
a drive shaft rotatably driven by the torque-generating body, the drive shaft having a proximal end, an opposing distal end and a longitudinal axis extending therebetween, the proximal end of the drive shaft being operatively engaged to the distal end of the torque-generating body, wherein rotation of said handle about the longitudinal axis causes the drive shaft to rotate;
an anti-torque device where a comprised of an elongated and generally hollow member proximal end of the anti-torque device is fixed from rotating relative to at least a portion of the torque-generating body; and
an end member provided at a distal end of the torque-generating body, the end member having a noncircular shape in cross-section, where the drive shaft is rotatably received within a central opening of the end member,
wherein the proximal end of the anti-torque device comprises a central opening which is slidably engaged to a corresponding longitudinally extending receiving face provided on the end member,
wherein a portion of the central opening that engages the longitudinally extending receiving face and the corresponding longitudinally extending receiving face are non-threaded surfaces.
2 . The device of claim 1 , wherein a distal end of the anti-torque device including the engagement portion is fixed from rotating relative to at least a portion of one of a pedicle screw, a locking cap and a fixation rod.
3 . The device of claim 1 , wherein the anti-torque device and torque-generating body cooperate to create a generally balanced reaction between a locking torque T L generated by the torque-generating body and an opposite reaction torque T R generated by the anti-torque device.
4 . The device of claim 3 , wherein the torque T L generated by the drive shaft of the torque-generating body is provided to one of a locking cap and a pedicle screw, and the opposite reaction torque T R generated by the anti-torque device is provided to one of the locking cap, the pedicle screw and a fixation rod.
5 . The device of claim 1 , wherein the torque-generating body is one of a motorized power tool, a pressurized fluid or a hand-actuated screwdriver.
6 . The device of claim 1 , wherein the anti-torque device is removably attached to the torque-generating body.
7 . The device of claim 1 , wherein the proximal end of the anti-torque device may selectively engage at least a portion of one or more generally unique distal portions of the torque-generating body.
8 - 14 . (canceled)
15 . The device of claim 1 , wherein the anti-torque device comprises a cylindrical member having an opening formed on a side wall of the cylindrical member proximate a connection point between the distal end of the drive shaft and at least a portion of one of a locking cap and a pedicle screw,
wherein a distal engagement portion of the anti-torque device includes radially spaced-apart archways that extend radially inwardly from the distal end of the anti-torque device, the archways radially spaced-apart from the opening.
16 . The device of claim 15 , wherein a portion of one of the archways engages at least a portion of a fixation rod to maintain the distal end of the anti-torque device stationary.
17 . The device of claim 1 , wherein the torque-generating body is connected to a worm gear by a shaft, and wherein rotation of the torque-generating body rotates the worm gear to turn the drive shaft.
18 . (canceled)
19 . The device of claim 1 , wherein a proximal end of the anti-torque device slidably engages the distal end of the torque-generating body.
20 - 45 . (canceled)
46 . The device of claim 1 , wherein at least a portion of the central opening of the anti-torque device has a cross-sectional shape corresponding to a cross-sectional shape of the end member of the torque-generating body.
47 . The device of claim 46 , wherein the cross-sectional shapes of both the central opening of the anti-torque device and the end member of the torque-generating body includes a generally straight portion extending between opposing curved side portions.
48 . The device of claim 1 , wherein the proximal end of the anti-torque device is rotatably fixedly attached to and fixed from rotating relative to at least a portion of the torque-generating body so as to not rotate with the drive shaft.
49 . The device of claim 1 , wherein the opposing distal end of the drive shaft sized and configured to engage at least a portion of one of a locking cap and a pedicle screw.