Modular pedicle screw system with tap and screw driver device

摘要

A modular dynamic pedicle screw system including anchoring device having a threaded shank for anchoring within a vertebra, an intermediate element and a head portion configured to receive and secure a rigid or non-rigid stabilization rod. The threaded shank, the intermediate element and the head portion of the anchoring device are cannulated to permit percutaneous implantation of the device. The intermediate portion is designed to be removable from the threaded shank portion subsequent to implantation of the anchoring device to enable substitution of another intermediate element having different dynamic characteristics. The dynamic stabilization system includes an adjustable torque limiting device that is interchangeable between a tap device and a screw driver. The torque device provides information relative to the patient's bone quality inter-operatively in order to determine the appropriate modulus of elasticity for the dynamic pedicle screw.

主权项

1. A kit for a modular screw stabilization system comprising;
individual components which when assembled form a modular pedicle screw, said individual components including a plurality of head portions, a plurality of intermediate portions, and a plurality of threaded shank portions; each of said plurality of head portions include a cylindrical wall with diametrically opposed grooves that extend downwards from a top of said cylindrical wall, said grooves are sized and configured to receive one or more rods within said diametrically opposed grooves, each of said head portions having a top, a bottom, and a longitudinal axis, each of said plurality of head portions further including a first channel formed coincident with said longitudinal axis and open at the top and the bottom of each of said plurality of head portions, and a first coupling element adapted for engagement with an upper coupling member associated with each of said intermediate portions, each of said plurality of intermediate portions include an upper coupling member having an upper cylindrical portion, a cylindrical post portion depending there from, and a cylindrical interengaging portion depending from the cylindrical post portion, a lower coupling member having a lower cylindrical portion, a hollow cylindrical wall extending upwardly from the lower cylindrical portion, an upper portion of the hollow cylindrical wall terminating in an annular flange that extends radially inward to form a cylindrical cavity having a reduced diameter aperture, and a material having a predetermined modulus of elasticity separating said upper coupling member and said lower coupling member, each of said plurality of intermediate portions having a top, a bottom and a longitudinal axis, each of said plurality of intermediate portions including a second channel extending coincident with said longitudinal axis and open at said top and said bottom; each of said plurality of threaded shank portions having a top, a bottom and a longitudinal axis, each of said plurality of threaded shank portions further including a threaded and tapered outer surface and a second coupling member formed at one end thereof and adapted for engagement with said lower coupling member of said intermediate portion, each of said plurality of threaded shank portions and each of said second coupling members having a third channel formed coincident with said longitudinal axis of each of said plurality of threaded shank portions and open at the top and bottom of each of said plurality of threaded shank portions, said first, second and third channels are configured to be in alignment with one another, whereby a wire can pass freely from the open bottom end of said threaded shank portion, through said intermediate portion, and out the open top end of said head portion and be completely removed from the pedicle screw; one or more rods; and a torque drive device for tapping a hole for said pedicle screws or driving said screws into said hole.