Sleeve assembly for spinal stabilization system and methods of use

• US 20060293693A1
• Filed: 07/06/2005
• Published: 12/28/2006
• Est. Priority Date: 06/08/2005
• Status: Active Grant

• Current Assignee: Spine Innovation, LLC
• Original Assignee: Spine Innovation, LLC
• Inventors: Farr, Morteza M., Keane, Ciaran
• Granted Patent: US 7,749,233 B2
• Time in Patent Office: Days
• US Class Current: 606/104
• CPC Class Codes: A61B 17/7037 wherein pivoting is blocked when the rod is clamped
• CPC Class Codes: A61B 17/7085 for insertion of a longitudinal element down one or more hollow screw or hook extensions, i.e. at least a part of the element within an extension has a component of movement parallel to the extension's axis
• CPC Class Codes: A61B 2090/061 for measuring dimensions, e.g. length
• CPC Class Codes: Y10S 606/916 Tool for installing or removing orthopedic fastener

Abstract

The present invention is a one or two-part sleeve assembly for use during minimally invasive spinal stabilization surgery. An outer sleeve is designed to slide over the coupling between a polyaxial screw and an inner sleeve so as to prevent the screw from becoming disengaged from the inner sleeve during surgery. The outer sleeve includes a lower generally cylindrical wall having a slot, and an upper extension having an outwardly protruding manipulation handle attached to it. The slot in the lower section extends the entire length of the cylindrical wall, giving it a generally “C” shaped cross section. This slot corresponds with a similar slot on the inner sleeve for receiving a stabilizing rod to be attached to the polyaxial screw during surgery. The interior diameter of the lower section is approximately the same as the outer diameter of the inner sleeve, so that the outer sleeve may slide snugly over the inner sleeve and the screw coupling. In addition, the edges of the cylindrical wall adjacent to the longitudinal slot are flattened so as to conform to the shape of the inner sleeve and the head portion of the polyaxial screw where it couples with the inner sleeve.

Claims

1. An assembly for use during minimally invasive spinal stabilization surgery comprising a slotted inner sleeve that couples to a polyaxial screw, and a slotted outer sleeve that slides over said inner sleeve and a portion of said screw to prevent the coupling between said inner sleeve and said screw from becoming disengaged during surgery.

2. The sleeve assembly of claim 1 wherein each of said sleeves has a generally cylindrical cross section, and the interior diameter of the outer sleeve is approximately the same as the exterior diameter of the inner sleeve.

3. The sleeve assembly of claim 2 wherein the outer sleeve has an upper extension and an outwardly protruding handle attached to said extension.

4. The sleeve assembly of claim 2 wherein the inner sleeve has a first longitudinal slot running the length of said inner sleeve, and said outer sleeve has a first longitudinal slot running the length of said outer sleeve, each of said first slots being aligned with each other when the sleeves are engaged.

5. The sleeve assembly of claim 4 wherein the inner sleeve has a second longitudinal slot running along a length of said inner sleeve across from said first slot, and said outer sleeve has a second longitudinal slot running along a length of said outer sleeve across from said first slot, each of said second slots being aligned with each other when the sleeves are engaged.

6. The sleeve assembly of claim 2 wherein said inner sleeve has at least one indented key that corresponds to at least one recessed slot in a head of said polyaxial screw.

7. The sleeve assembly of claim 2 wherein the inner sleeve has a plurality of register keys that correspond to a plurality of register flats on the outer sleeve that allow the outer sleeve to slide over the inner sleeve only when said keys and flats are properly oriented.

8. The sleeve assembly of claim 2 wherein the cylindrical section of the outer sleeve has a tapered leading edge and a tapered trailing edge.

9. An assembly for use during minimally invasive spinal stabilization surgery comprising a slotted inner sleeve having a generally cylindrical cross section that couples to a polyaxial screw, and a slotted outer sleeve having a generally cylindrical cross section that slides over said inner sleeve and a portion of said screw to prevent the coupling between said inner sleeve and said screw from becoming disengaged during surgery, said outer sleeve having an upper extension and an outwardly protruding handle attached to said extension, said inner sleeve having at least one indented key that corresponds to at least one recessed slot in a head of said polyaxial screw, said inner sleeve having a plurality of register keys that correspond to a plurality of register flats on the outer sleeve that allow the outer sleeve to slide over the inner sleeve only when said keys and flats are properly oriented, each of said sleeves having a first longitudinal slot running the length of the sleeve, said first slots being aligned with each other, each of said sleeves having a second longitudinal slot running along a length of the sleeve opposite from said first slots, said second slots being aligned with each other.

10. A sleeve assembly for use during minimally invasive spinal stabilization surgery comprising a generally cylindrical inner sleeve assembly having a first longitudinal slot running the length of the sleeve, a plurality of registers extending along the edges of said slot, and a second partial longitudinal slot extending from a bottom edge of the inner sleeve across from said first slot;

an outer sleeve assembly having a generally cylindrical lower slotted section, a plurality of register flats corresponding to the registers of said inner sleeve, an upper extension having an outwardly protruding handle thereon, and a second partial slot extending from the bottom edge the lower slotted section across from said first slot;

such that the outer sleeve assembly slides over the inner sleeve assembly in an orientation determined by the mating of the registers of the inner sleeve assembly and the flats of the outer sleeve assembly to prevent a polyaxial screw assembly from becoming disengaged from the inner sleeve assembly during surgery.

11. A method of using a sleeve assembly during minimally invasive spinal surgery comprising:

a. coupling an inner sleeve assembly to a polyaxial screw assembly using a pair of registers on said inner sleeve that engage a pair of recesses in a head of said screw assembly, said inner sleeve having at least one slot extending longitudinally along a length thereof and having registers along the edges of said slot;

b. fastening the polyaxial screw assembly to a vertebrae body using force transmitted through said inner sleeve; and

c. sliding an outer sleeve assembly over said inner sleeve assembly to maintain the coupling between said screw assembly and said inner sleeve during surgery, said outer sleeve assembly comprising a generally cylindrical lower slotted section, a plurality of register flats corresponding to registers on said inner sleeve, and an upper extension having an outwardly protruding handle thereon.

12. The method of claim 11 comprising the additional steps of:

d. repeating steps a-c for a second inner and outer sleeve assembly coupled to a second polyaxial screw assembly;

e. inserting a reinforcing between the two sleeve assemblies such that said rod extends into the aligned slots in each of said assemblies; and

f. affixing the rod to the polyaxial screws of the first and second assemblies.

13. The method of claim 12 comprising the additional steps of:

g. removing the first and second outer sleeves from the first and second inner sleeves; and

h. disengaging the first and second inner sleeves from the first and second polyaxial screw assemblies.