Lateral approach expandable spinal implant and method

• US 9,615,937 B2
• Filed: 11/16/2015
• Issued: 04/11/2017
• Est. Priority Date: 09/09/2011
• Status: Expired due to Fees

• Current Assignee: Spine Wave Incorporated
• Original Assignee: Spine Wave Incorporated
• Inventors: Barreiro, Peter
• Primary Examiner(s): MERENE, JAN CHRISTOP L
• Application Number:
  US14/941,749
• Publication Number:
  US 20160166399A1
• Time in Patent Office: 512 Days
• CPC Class Codes: A61B 2017/0256 for the spine
• 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 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 2002/3008 radio-opaque, e.g. radio-opaque markers
• 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 2002/305 Snap connection
• CPC Class Codes: A61F 2002/3052 unrestrained in only one direction, e.g. moving unidirectionally
• CPC Class Codes: A61F 2002/30556 for adjusting thickness
• CPC Class Codes: A61F 2002/30579 with mechanically expandable devices, e.g. fixation devices
• CPC Class Codes: A61F 2002/30599 stackable
• CPC Class Codes: A61F 2002/30601 telescopic
• CPC Class Codes: A61F 2002/30843 Pyramidally-shaped
• CPC Class Codes: A61F 2002/30904 serrated profile, i.e. saw-toothed

Abstract

An expandable interbody fusion device configured for placement into the intradiscal space between vertebral bodies in a lumbar spine from a lateral approach. The device is expanded by the insertion of a plurality of wafers into the device in situ. The length of the device is configured to extend on the vertebral body endplate from pedicle to pedicle and to reside interiorly of the ring apophysis with at least a portion of the device resting on the area of increased bone density at the posterior portion of the endplate between the pedicles.

Claims

1. A method of inserting an expandable interbody fusion device from the lateral approach into the intradiscal space of the lumbar spine, the intradiscal space being divided by a transverse centerline extending across the lateral width of said intradiscal space that defines an anterior portion and a posterior portion, comprising the steps of:

providing an access corridor to the spine from the lateral approach;

providing an elongate expandable device having a length and a width, said length being less than the lateral width of the vertebral endplate interiorly between the peripheral ring apophysis and not less than the pedicle-to pedicle spacing of the vertebral body;

inserting said device into the intradiscal space between opposing vertebral bodies entirely within the interior of said ring apophysis of said endplate with at least a portion of the width of said device being disposed in the anterior portion of said intradiscal space and a greater portion of the width of said device being disposed in the posterior portion of said intradiscal space and residing on the area of endplate increased bone density at the posterior portion of the endplates between the pedicles; and

then

expanding the expandable device in situ to increase the height of the intradiscal space and stabilize the spine.

2. The method of claim 1, wherein said elongate expandable device comprises a superior endplate, an inferior endplate and an expansion structure therebetween, and wherein said expansion structure is expanded to increase the height of said device.

3. The method of claim 2, wherein said expansion structure comprises a plurality of elements that are introduced into said device individually consecutively to form a stack of elements between said superior endplate and said inferior endplate.

4. The method of claim 2, wherein the height of said device is increased from an unexpanded height to an expanded height, said expanded height being at least 50% greater than said unexpanded height.

5. The method of claim 1, further including the step of nerve monitoring during the creation of said access corridor.

6. The method of claim 5, further including the step of dilating said access corridor.

7. The method of claim 6, further including the step of enlarging the access corridor, and wherein said device is inserted through said enlarged access corridor.

8. The method of claim 1, wherein a bone filler is inserted into said intradiscal space adjacent said expanded device.

9. The method of claim 8, wherein said bone filler is a bone graft and is injected under pressure to stress load the bone graft against the vertebral endplates of opposing vertebral bodies communicating with said intradiscal space.

10. The method of claim 9, wherein said bone graft is placed prior to insertion of device.

11. The method of claim 9, wherein after insertion of said device said bone graft is placed adjacent the device only in said anterior portion of said intradiscal space.