Expandable spinal fusion implant, related instruments and methods

• US 10,350,084 B1
• Filed: 09/14/2016
• Issued: 07/16/2019
• Est. Priority Date: 10/22/2012
• Status: Active Grant

• Current Assignee: Nuvasive Incorporated
• Original Assignee: Nuvasive Incorporated
• Inventors: Lin, Erika, Malik, Jeremy, Donahoe, Ryan, Stein, Christopher, Hannah, David
• Primary Examiner(s): Ku, Si Ming
• Application Number:
  US15/265,300
• Time in Patent Office: 1,035 Days
• CPC Class Codes: A61B 17/8819 characterised by the introducer proximal part, e.g. cannula handle, or by parts which are inserted inside each other, e.g. stylet and cannula A61B17/8825 takes precedence
• CPC Class Codes: A61B 17/8833 Osteosynthesis tools specially adapted for handling bone cement or fluid fillers; Means for supplying bone cement or fluid fillers to introducing tools, e.g. cartridge handling means
• CPC Class Codes: A61F 2/30749 Fixation appliances for connecting prostheses to the body
• CPC Class Codes: A61F 2/30771 applied in original prostheses, e.g. holes or grooves
• CPC Class Codes: A61F 2/4455 for the fusion of spinal bodies, e.g. intervertebral fusion of adjacent spinal bodies, e.g. fusion cages intervertebral discs A61F2/442
• CPC Class Codes: A61F 2/4465 having a circular or kidney shaped cross-section substantially perpendicular to the axis of the spine
• CPC Class Codes: A61F 2/447 substantially parallelepipedal, e.g. having a rectangular or trapezoidal cross-section
• CPC Class Codes: A61F 2/4601 for introducing bone substitute, for implanting bone graft implants or for compacting them in the bone cavity
• CPC Class Codes: A61F 2/4611 of spinal prostheses
• CPC Class Codes: A61F 2/4684 Trial or dummy prostheses
• CPC Class Codes: A61F 2002/2835 Bone graft implants for filling a bony defect or an endoprosthesis cavity, e.g. by synthetic material or biological material
• CPC Class Codes: A61F 2002/30143 hexagonal
• CPC Class Codes: A61F 2002/302 toroidal, e.g. rings
• CPC Class Codes: A61F 2002/30383 made by laterally inserting a protrusion, e.g. a rib into a complementarily-shaped groove
• CPC Class Codes: A61F 2002/30405 made by screwing complementary threads machined on the parts themselves
• CPC Class Codes: A61F 2002/30471 connected by a hinged linkage mechanism, e.g. of the single-bar or multi-bar linkage type
• CPC Class Codes: A61F 2002/30494 Cooperating protrusions and recesses, e.g. radial serrations, located on abutting end surfaces of a longitudinal connection
• CPC Class Codes: A61F 2002/30505 spring biased
• CPC Class Codes: A61F 2002/30523 by means of meshing gear teeth
• CPC Class Codes: A61F 2002/30528 Means for limiting said movement
• CPC Class Codes: A61F 2002/30537 : adjustable
• CPC Class Codes: A61F 2002/30545 : for adjusting a diameter
• CPC Class Codes: A61F 2002/3055 : for adjusting length
• CPC Class Codes: A61F 2002/30578 : having apertures, e.g. for receiving fixation screws
• CPC Class Codes: A61F 2002/30579 : with mechanically expandable devices, e.g. fixation devices
• CPC Class Codes: A61F 2002/30593 : hollow
• CPC Class Codes: A61F 2002/30622 : Implant for fusing a joint or bone material
• CPC Class Codes: A61F 2002/30624 : Hinged joint, e.g. with transverse axle restricting the movement
• CPC Class Codes: A61F 2002/30787 : inclined obliquely with respect to each other
• CPC Class Codes: A61F 2002/30831 : perpendicular with respect to each other
• CPC Class Codes: A61F 2002/30843 : Pyramidally-shaped
• CPC Class Codes: A61F 2002/4415 : elements of the prosthesis being arranged in a chain like manner
• CPC Class Codes: A61F 2002/4627 : with linear motion along or rotating motion about the instrument axis or the implantation direction, e.g. telescopic, along a guiding rod, screwing inside the instrument
• CPC Class Codes: A61F 2002/4629 : connected to the endoprosthesis or implant via a threaded connection
• CPC Class Codes: A61F 2002/4635 : using minimally invasive surgery

Abstract

A system for performing interbody fusion surgery including an expandable intervertebral spacer and specialized instruments for choosing the correct size of implant, implanting the device within the intervertebral space, and for delivery of bone graft or bone substitute to the interior of the implant.

Claims

1. A method of inserting an intervertebral spacer into an intervertebral space of a patient, the method comprising:

a. accessing the intervertebral space;

b. removing an intervertebral disc in need of replacement present in the intervertebral space;

c. inserting the intervertebral spacer into the intervertebral space, the intervertebral spacer comprising;

i. a lateral side having a proximal end and a distal end and comprising a first plurality of links joined by a first plurality of joints;

ii. a medial side having a proximal end and a distal end and comprising a second plurality of links joined by a second plurality of joints;

iii. a proximal end including an insertion link having an aperture dimensioned to receive an insertion tool, said insertion link joined to proximal ends of the lateral side and the medial side;

iv. a distal end;

v. a first support face configured to contact a first vertebral body endplate and a second support face opposite said first support face configured to contact a second vertebral body endplate; and

vi. a positioner gear assembly housed in the distal end of the intervertebral spacer and configured to maintain the intervertebral spacer in an expanded configuration,

 

wherein (i) said intervertebral spacer has an insertion configuration in which the intervertebral spacer is elongated, (ii) the lateral side and the medial side are linear, (iii) an axis of insertion of the intervertebral spacer info the intervertebral space is parallel to a longitudinal axis of the intervertebral spacer, (iv) when in the expanded configuration the lateral and medial sides are displaced to define a graft aperture, and (v) the intervertebral spacer has a hexagonal perimeter that is asymmetrical about the axis of insertion.

2. The method of claim 1 wherein the intervertebral spacer is bisected by a first axis parallel to a sagittal plane when the spacer is in the expanded configuration.

3. The method of claim 2 wherein the perimeter of the intervertebral spacer is symmetrical about the first axis.

4. The method of claim 1 wherein at least one of the links of the lateral side of the intervertebral spacer comprise a window.

5. The method of claim 4 wherein at least one of the links of the medial side of the intervertebral spacer comprise a window.

6. The method of claim 1 wherein at least one of the links of the medial side of the intervertebral spacer comprise a window.

7. The method of claim 1 wherein the intervertebral spacer'"'"'s lateral side has a first height at the distal end and a second height at the proximal end and wherein the first height is greater than the second height.

8. The method of claim 7 wherein the intervertebral spacer'"'"'s medial side has a first height at the distal end and a second height at the proximal end and wherein the first height is greater than the second height.

9. A method of inserting an intervertebral spacer into an intervertebral space of a patient, the method comprising:

a. accessing the intervertebral space;

b. removing an intervertebral disc in need of replacement present in the intervertebral space;

c. inserting the intervertebral spacer into the intervertebral space, the intervertebral spacer comprising;

i. a lateral side having a proximal end and a distal end and comprising a first plurality of links joined by a first plurality of joints;

ii. a medial side having a proximal end and a distal end and comprising a second plurality of links joined by a second plurality of joints;

iii. a proximal end and a distal end;

iv. a first support face configured to contact a first vertebral body endplate;

v. a second support face opposite said first support face configured to contact a second vertebral body endplate,

wherein when the intervertebral spacer is in an expanded configuration the lateral and medial sides are displaced to define a graft aperture and the intervertebral spacer has a hexagonal perimeter that is asymmetrical about an axis of insertion.

10. The method of claim 9 wherein the intervertebral spacer has an insertion configuration in which the intervertebral spacer is elongated and the lateral side and the medial side are linear and the axis of insertion into the intervertebral space that is parallel to a longitudinal axis of the intervertebral spacer.

11. The method of claim 9 wherein the intervertebral spacer is bisected by a first axis parallel to a sagittal plane when the spacer is in the expanded configuration.

12. The method of claim 11 wherein the perimeter of the intervertebral spacer is symmetrical about the first axis.

13. The method of claim 9 wherein at least one of the links of the lateral side of the intervertebral spacer comprise a window.

14. The method of claim 9 wherein at least one of the links of the medial side of the intervertebral spacer comprise a window.

15. The method of claim 9 wherein the intervertebral spacer'"'"'s lateral side has a first height at the distal end and a second height at the proximal end and wherein the first height is greater than the second height.

16. The method of claim 15 wherein the intervertebral spacer'"'"'s medial side has a first height at the distal end and a second height at the proximal end and wherein the first height is greater than the second height.

17. A method of inserting an intervertebral spacer into an intervertebral space of a patient, the method comprising:

inserting the intervertebral spacer into the intervertebral space, the intervertebral spacer comprising;

i. a lateral side having a proximal end and a distal end and comprising a first plurality of links joined by a first plurality of joints;

ii. a medial side having a proximal end and a distal end and comprising a second plurality of links joined by a second plurality of joints;

iii. a proximal end and a distal end;

iv. a first support face configured to contact a first vertebral body endplate; and

v. a second support face opposite said first support face configured to contact a second vertebral body endplate, wherein the intervertebral spacer comprises a positioner gear assembly housed in the distal end of the intervertebral spacer and configured to maintain the intervertebral spacer in an expanded configuration, wherein the positioner gear assembly comprises a positioner gear having a biasing element and an arc shaped body.

18. The method of claim 17, wherein the arc shaped body comprises a plurality of radially cut teeth configured to allow expansion or contraction of the spacer to a predetermined size.