Rod reducer, compressor, distractor system

Abstract

A compressor/distractor system for operating on a spine is disclosed. The system includes two rod reducers which each advance a spinal rod into the shoulder portion of a pedicle screw. Each rod reducer includes an inner member, an outer member, and a pair of gripping members. Each outer member receives and advances the spinal rod into the pedicle screw. The outer member also includes a through slot which receives the proximal end of each of the pair of gripping members which may limit the longitudinal translation of the outer member with respect to the inner member. The compressor/distractor system may include a compressor/distractor device which has a compressing, a distracting, and a neutral configuration. A method for using the minimally invasive rod reducers with the compressor/distractor system to secure at least two pedicle screws in desired positions on a spinal rod is also disclosed.

What is claimed: 
     
       1. A method for manipulating vertebrae comprising:
 accessing the spinal area of a patient having a pedicle screw secured to each of at least two vertebrae; 
 engaging each pedicle screw with an inner member having distal and proximal ends defining a longitudinal axis therebetween, the distal end of each inner member receiving a head of the pedicle screw; 
 advancing an outer member having distal and proximal ends distally along each of the inner members by rotating the proximal end of each of the outer members relative to each inner member, a pair of receiving slots on the distal end of each outer member receiving a portion of a spinal rod, each pair of receiving slots advancing the spinal rod into a saddle portion of the head of each pedicle screw; 
 attaching a force applying device and a fulcrum to an outer surface of each outer member, the force applying device including first and second hook members and having a compressing configuration when the first and second hook members are attached to each outer member with each of the outer members between the first and second hook members and a distracting configuration when the first and second hook members are attached to each outer member with the first and second hook members between each of the outer members; 
 manipulating each outer member with the force applying device until each of the pedicle screws is in a desired position with respect to the spinal rod; and 
 securing each pedicle screw to the spinal rod with a set screw. 
 
     
     
       2. The method of  claim 1 , wherein the force applying device further includes a neutral configuration and the second hook member includes a switch assembly having a first, a second, and a third position, each position corresponding to a configuration of the force applying device. 
     
     
       3. The method of  claim 1 , wherein the first and second hook members each include a hook portion, each hook portion having a compressing hook and a distracting hook. 
     
     
       4. The method of  claim 1 , wherein the fulcrum is attached to a gripping portion of each outer member. 
     
     
       5. The method of  claim 1 , wherein the step of advancing further includes attaching an anti-torque handle to a distal segment of each outer member and attaching a turning handle to a proximal segment of each outer member. 
     
     
       6. The method of  claim 1 , wherein the method further includes the step of inserting at least one set screw through an inner member and at least partially locking the rod to at least one of the pedicle screws before the step of manipulating the each outer member. 
     
     
       7. A method for manipulating vertebrae comprising:
 securing a first elongate member to a first pedicle screw that is secured in a first vertebra; 
 securing a second elongate member to a second pedicle screw that is secured in a second vertebra; and 
 manipulating the first and second elongate members with a force applying device until the first and second pedicle screws are in a desired position, the force applying device having first and second hook members, each hook member having a distracting hook and a compressing hook. 
 
     
     
       8. The method according of to  claim 7 , wherein manipulating the first and second elongate members with the force applying device includes positioning the first and second elongate members between the first and second hook members of the force applying device to compress the first and second elongate members towards one another. 
     
     
       9. The method according of to  claim 7 , wherein manipulating the first and second elongate members with the force applying device includes positioning the first and second hook members of the force applying device between the first and second elongate members to distract the first and second elongate members away from one another. 
     
     
       10. The method according of to  claim 7 , further comprising positioning a fulcrum over a distal proximal end of each of the first and second elongate members before manipulating the first and second elongate members with the force applying device. 
     
     
       11. The method according to  claim 10 , wherein manipulating the elongate members with the force applying device includes engaging the first elongate member with the first hook member between the fulcrum and the pedicle screw and engaging the second elongate member with the second hook member between the fulcrum and the pedicle screw. 
     
     
       12. The method according of to  claim 7 , further comprising:
 reducing a spinal rod into a head of the first pedicle screw with the first elongate member; and 
 reducing the spinal rod into a head of the second pedicle screw with the second elongate member. 
 
     
     
       13. A method for manipulating vertebrae comprising:
 securing a first elongate member to a first pedicle screw that is secured in a first vertebra; 
 securing a second elongate member to a second pedicle screw that is secured in a second vertebra; and 
 manipulating the first and second elongate members with a force applying device until the first and second pedicle screws are in a desired position, the force applying device having a compressing configuration, a distracting configuration, and a neutral configuration and including two hook members, at least one of the two hook members including switch assembly for selecting a respective one of the compressing, distracting, and neutral configurations, the switch assembly defining detents which each correspond to a respective one of the compressing, distracting, and neutral configurations of the force applying device. 
 
     
     
       14. The method according to claim 10, wherein positioning the fulcrum over the proximal end of each of the first and second elongate members comprises positioning each of the first and second elongate members in a respective through hole of a plurality of through holes extending through the fulcrum. 
     
     
       15. The method according to claim 14, wherein the plurality of through holes extending through the fulcrum includes multiple through holes for each of the first and second elongate members, the through holes being spaced apart from one another such that each of the first and second elongate members can be selectively received within different ones of the multiple through holes, so as to thereby define a variable spacing between the first and second elongate members at a location where the fulcrum receives the first and second elongate members. 
     
     
       16. The method according to claim 15, wherein the plurality of first and second through holes are aligned along an axis of the fulcrum, the through holes being spaced apart along the axis. 
     
     
       17. The method according to claim 14, wherein each of the plurality of through holes includes a bearing ring received within the respective through hole. 
     
     
       18. The method of claim 1, wherein the fulcrum includes a plurality of through holes configured to receive each of the outer members therein. 
     
     
       19. The method of claim 18, wherein the plurality of through holes in the fulcrum includes multiple through holes for each of the outer members, the through holes being spaced apart from one another such that each outer member can be selectively received within different ones of the multiple through holes, so as to thereby define a variable spacing between the outer members at a location where the fulcrum receives the outer members. 
     
     
       20. The method of claim 19, wherein the plurality of through holes are aligned along an axis of the fulcrum, the through holes being spaced apart along the axis. 
     
     
       21. The method of claim 18, wherein each of the plurality of through holes includes a bearing ring received within the respective through hole. 
     
     
       22. The method of claim 13, further comprising engaging the first and second elongate members with a fulcrum by positioning each of the first and second elongate members in a respective through hole of a plurality of through holes extending through the fulcrum. 
     
     
       23. The method of claim 22, wherein the plurality of through holes extending through the fulcrum includes multiple through holes for each of the first and second elongate members, the through holes being spaced apart from one another such that each of the first and second elongate members can be selectively received within different ones of the multiple through holes, so as to thereby define a variable spacing between the first and second elongate members at a location where the fulcrum receives the first and second elongate members. 
     
     
       24. The method of claim 23, wherein the plurality of first and second through holes are aligned along an axis of the fulcrum, the through holes being spaced apart along the axis. 
     
     
       25. The method of claim 22, wherein each of the plurality of through holes includes a bearing ring received within the respective through hole. 
     
     
       26. A method for manipulating vertebrae comprising:
 securing a first elongate member to a first pedicle screw that is secured in a first vertebra;   securing a second elongate member to a second pedicle screw that is secured in a second vertebra;   selecting a selected spacing from a plurality of different possible spacings provided by a fulcrum having a plurality of receptacles configured to receive the first and second elongate members therein, the spacings each being characterized by a length dimension defined between any first one of the receptacles and any second one of the receptacles, such that the selected spacing is defined by the length dimension between a selected first one of the receptacles and a selected second one of the receptacles;   engaging the first and second elongate members with the fulcrum by receiving the first elongate member within the selected first one of the receptacles and receiving the second elongate member within the selected second one of the receptacles so as to fix a distance between the first and second elongate members at a fulcrum location along the first and second elongate members, the distance being the length dimension defined between the selected first one of the receptacles and the selected second one of the receptacles; and   applying compression and/or distraction forces to the first and second elongate members while the fulcrum fixes the distance between the first and second elongate members at the fulcrum location.   
     
     
       27. The method of claim 26, wherein the first and second receptacles are through holes extending through the fulcrum. 
     
     
       28. The method of claim 26, wherein the plurality of first and second receptacles are aligned along an axis of the fulcrum, the receptacles being spaced apart along the axis. 
     
     
       29. The method of claim 26, wherein each of the plurality of first and second receptacles includes a bearing ring received therein. 
     
     
       30. The method of claim 26, wherein each of the first and second elongate members is a rod reducer. 
     
     
       31. The method of claim 26, wherein each of the plurality of different possible spacings provided by the fulcrum corresponds to a different respective angle defined between the first and second elongate members when the first and second elongate members are secured to the respective first and second pedicle screws and when the first and second members are engaged with the fulcrum at the fulcrum location. 
     
     
       32. The method of claim 26, wherein the step of applying compression and/or distraction forces to the first and second elongate members comprises engaging a force applying device to the first and second elongate members, the force applying device being engageable to a plurality of force applying locations on each of the first and second elongate members. 
     
     
       33. The method of claim 32, wherein the step of engaging the force applying device to the first and second elongate members comprises engaging the force applying device to the first and second elongate members at a selected one of the force applying locations, the selected force applying location being between the fulcrum and the first and second pedicle screws. 
     
     
       34. The method of claim 26, wherein the fulcrum is engageable with the first and second elongate members by receiving the first and second elongate members at a variety of different fulcrum locations along a respective portion of each of the first and second elongate members.