Patent ID: 8088149

Claim:
A dynamic vertebral stabilization system, which comprises: a) at least two pedicle screws installable at an initial distance ΔD in adjacent vertebrae of a subject, each pedicle screw having a threaded shaft that is screwable into a vertebra segment and a pedicle screw head attached to the shaft, wherein the pedicle screw head comprises a distal set screw receiver and either an anchor receiver slot or an anchor receiving passage intermediate the threaded shaft and the set screw receiver; b) at least two set screws threadable into the respective set screw receivers of the at least two pedicle screws; c) an externally threaded connecting rod extending along an axis; and d) at least two anchors, each having a cross-sectional dimension that is receivable in a respective one of the anchor receiver slots or anchor receiving passages of the at least two pedicle screws, wherein each anchor has internal threads that are complementary with the threads of the connecting rod; e) wherein, in use, the first and second anchors are threadable onto the connecting rod in a spaced relationship of substantially the initial distance ΔD, and the connecting rod supporting the first and second anchors is receivable in the anchor receiver slots or the anchor receiving passages provided in the heads of the first and second pedicle screws having been threaded at the initial distance ΔD into adjacent vertebrae of the subject, and f) wherein with the first and second set screws threaded into the set screw receivers of the first and second pedicle screw heads in an untightened condition contacting the first and second anchors, the connecting rod is threadingly adjustable with respect to the anchors to thereby axially adjust the distance between the pedicie screws along the axis of the connecting rod, thus enabling fine adjustment of the initial distance ΔD to a set adjusted distance prior to further threading of the first and second set screws into a tightened condition compressing the first and second anchors into a fixed spatial relationship on the connecting rod.