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 proximal 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 of the drive shaft causes the drive shaft to rotate;
an anti-torque device where a 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 the 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 includes an engagement portion that 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 anti-torque device is removably attached to the torque-generating body.
6 . 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.
7 . The device of claim 1 ,
wherein a distal engagement portion of the anti-torque device includes radially spaced-apart archways that extend radially inwardly from a distal end of the anti-torque device.
8 . The device of claim 7 , 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.
9 . 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 the cross-sectional shape of the end member of the torque-generating body.
10 . The device of claim 9 , wherein the cross-sectional shapes of both the central opening of the anti-torque device and the end member of the torque-generating body include a generally straight portion extending between opposing curved side portions.
11 . 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.
12 . The device of claim 1 , wherein the opposing distal end of the drive shaft is sized and configured to engage at least a portion of one of a locking cap and a pedicle screw.