Spinal stabilization implant system

• US 5,676,703 A
• Filed: 07/24/1996
• Issued: 10/14/1997
• Est. Priority Date: 05/11/1994
• Status: Expired due to Term

• Current Assignee: Steven D. Gelbard
• Original Assignee: Steven D. Gelbard
• Inventors: Gelbard, Steven D.
• Primary Examiner(s): Milano, Michael J.
• Application Number:
  US08/692,850
• Time in Patent Office: 447 Days
• Field of Search: 606/61, 606/62, 606/72, 606/73, 623/17, 411/383, 411/384, 411/389, 411/400
• US Class Current: 606/305
• CPC Class Codes: A61B 17/7005 Parts of the longitudinal elements, e.g. their ends, being specially adapted to fit in the screw or hook heads
• CPC Class Codes: A61B 17/7007 Parts of the longitudinal elements, e.g. their ends, being specially adapted to fit around the screw or hook heads
• CPC Class Codes: A61B 17/701 Longitudinal elements with a non-circular, e.g. rectangular, cross-section A61B17/7005, A61B17/7007 take precedence
• CPC Class Codes: A61B 17/7032 Screws or hooks with U-shaped head or back through which longitudinal rods pass
• CPC Class Codes: A61B 17/7049 Connectors, not bearing on the vertebrae, for linking longitudinal elements together A61B17/7055, A61B17/7053, A61B17/7019 take precedence
• CPC Class Codes: A61B 17/7058 Plates mounted on top of bone anchor heads or shoulders
• CPC Class Codes: A61B 17/7059 Cortical plates A61B17/7007, A61B17/7058 take precedence
• CPC Class Codes: A61B 17/80 Cortical plates , i.e. bone plates; Instruments for holding or positioning cortical plates, or for compressing bones attached to cortical plates

Abstract

A surgical implant system for the stabilization of a human spine by fixation of the vertebra utilizing a stabilization cross-link spinal implant system. The system utilizes self-tapping screws having bifurcated protruding members to support an alignment rod, the protruding members available for placement of a fixed or variable traverse cross-link member that couples to the protruding members by use of threaded nuts corresponding to the threaded portion of the outer surface of the protruding members. The externally threaded coupling method can also be use for pedicle, caudal, cranial, thoracic and the like hooks. Also shown is a two plate system for anterior cervical spine fixation.

Claims

1. A variable directional screw for use in combination with support brackets in a surgical implant for the stabilization of a human spine, said device comprising:

a metal sacral screw base having a first end and a second end, said first end having an insertion tip with a relatively coarse self-tapping thread extending from said insertion tip along substantial portion of said first end, said second end defined as a protruding shaft extending outwardly from said first end with at least a portion of said protruding shaft threaded, said protruding shaft having a diameter less than the diameter of said first end forming a side wall juncture between said first end and second end;

a first directional shaft having a coupling end and an engagement end, said coupling end including an aperture sized for slidable positioning over said protruding shaft of said second end; and

at least one nut having internal threads engageable with said threads of said protruding shaft;

wherein said first end is insertable into bone and said second end receptive to direct bracket coupling or to the coupling of said directional shaft allowing rotational and perpendicular positioning of said threaded shaft permitting coupling to a bracket at a perpendicular position, said nut locking said directional shaft in a fixed position.

2. The variable directional screw according to claim 1 wherein said side wall includes ridges for frictionally engaging said directional shaft.

3. The variable directional screw according to claim 1 wherein a side surface of said coupling end includes ridges for frictionally engaging said side wall of said first end.

4. The variable directional screw according to claims 2 or 3 wherein said ridges allow said first end and said directional shaft to interdigitate.

5. The variable directional screw according to claim 1 including a second direction shaft having a coupling end including an aperature sized for slidable positioning over said protruding shaft of said first directional shaft and a threaded protruding end with at least one nut having internal threads engageable with said threaded protruding shaft.

6. A variable directional screw for use in combination with support brackets as a surgical implant used in the stabilization of a human spine, said device comprising:

a metal sacral screw base having a first end and a second end, said first end having an insertion tip with a relatively coarse self-tapping thread extending from said insertion tip along a substantial portion of said first end, said second end defined as protruding shaft extending outwardly from said first end with at least a portion of said shaft threaded, said shaft having a diameter less than the diameter of said first end forming a side wall juncture between said first end and second end;

said side wall juncture including indexing ridges;

a first directional shaft having a coupling end and an engagement end, said coupling end including an aperture sized for slidable positioning over said shaft of said second end, a side surface of said coupling end including indexing ridges operatively associated with said indexing ridges of said side wall juncture;

and at least one nut having internal threads engageable with said threads of said protruding shaft;

wherein said first end is insertable into bone and said second end can be coupled directly to a bracket or is receptive to the coupling of said directional shaft allowing 360 degree rotation and perpendicular positioning of said threaded shaft with said ridges allowing said base and said directional shaft to interdigitate, said nut locking said directional shaft in a fixed position.

7. The variable directional screw according to claim 6 including a second direction shaft having a first end formed of a shoulder having a side surface engageable with the ridges of said first directional shaft, said shaft protruding perpendicular therefrom with at least one metal nut having internal threads engageable with said threaded protruding shaft.