Expandable ring intervertebral fusion device

• US 9,615,933 B2
• Filed: 09/15/2009
• Issued: 04/11/2017
• Est. Priority Date: 09/15/2009
• Status: Active Grant

• Current Assignee: Depuy Synthes Products Incorporated (Johnson & Johnson)
• Original Assignee: Depuy Synthes Products Incorporated (Johnson & Johnson)
• Inventors: Frasier, William, Renganathan, Narendren, Presbrey, Glen, Fisher, Michael A, Hawkins, John Riley
• Primary Examiner(s): WOODALL, NICHOLAS W
• Application Number:
  US12/559,537
• Publication Number:
  US 20110066192A1
• Time in Patent Office: 2,765 Days
• Field of Search: 606246-249, 623 1711- 1716, 623 111- 112, 623 115- 118, 623 12
• CPC Class Codes: A61F 2/441 made of inflatable pockets or chambers filled with fluid, e.g. with hydrogel
• CPC Class Codes: A61F 2/446 having a circular or elliptical cross-section substantially parallel to the axis of the spine, e.g. cylinders or frustocones
• 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 2/4611 of spinal prostheses
• CPC Class Codes: A61F 2002/2817 Bone stimulation by chemical reactions or by osteogenic or biological products for enhancing ossification, e.g. by bone morphogenetic or morphogenic proteins [BMP] or by transforming growth factors [TGF]
• CPC Class Codes: A61F 2002/30062 (bio)absorbable, biodegradable, bioerodable, (bio)resorbable, resorptive
• CPC Class Codes: A61F 2002/30092 using shape memory or superelastic materials, e.g. nitinol
• CPC Class Codes: A61F 2002/30131 horseshoe- or crescent- or C-shaped or U-shaped
• CPC Class Codes: A61F 2002/30224 cylindrical
• CPC Class Codes: A61F 2002/30289 helically-coiled
• CPC Class Codes: A61F 2002/30291 spirally-coiled, i.e. having a 2D spiral cross-section
• CPC Class Codes: A61F 2002/30476 locked by an additional locking mechanism
• CPC Class Codes: A61F 2002/3052 unrestrained in only one direction, e.g. moving unidirectionally
• CPC Class Codes: A61F 2002/30579 with mechanically expandable devices, e.g. fixation devices
• CPC Class Codes: A61F 2002/30583 filled with hardenable fluid, e.g. curable in-situ
• CPC Class Codes: A61F 2002/30594 slotted, e.g. radial or meridian slot ending in a polar aperture, non-polar slots, horizontal or arcuate slots
• CPC Class Codes: A61F 2002/30601 telescopic
• CPC Class Codes: A61F 2002/30672 temporary
• CPC Class Codes: A61F 2002/30677 Means for introducing or releasing pharmaceutical products, e.g. antibiotics, into the body
• CPC Class Codes: A61F 2002/4415 elements of the prosthesis being arranged in a chain like manner
• CPC Class Codes: A61F 2210/0004 : bioabsorbable
• CPC Class Codes: A61F 2210/0014 : using shape memory or superelastic materials, e.g. nitinol
• CPC Class Codes: A61F 2210/0085 : hardenable in situ, e.g. epoxy resins
• CPC Class Codes: A61F 2220/0025 : Connections or couplings between prosthetic parts, e.g. between modular parts; Connecting elements
• CPC Class Codes: A61F 2230/0013 : Horseshoe-shaped, e.g. crescent-shaped, C-shaped, U-shaped
• CPC Class Codes: A61F 2230/0069 : cylindrical
• CPC Class Codes: A61F 2230/0091 : helically-coiled or spirally-coiled, i.e. having a 2-D spiral cross-section
• CPC Class Codes: A61F 2250/0059 : temporary

Abstract

An expandable tube having a substantially semicircular unexpanded shape is inserted into the disc space after the disc material has been removed therefrom. A plurality of expandable lockable rings are passed over this tube in their unexpanded states and positioned along the anterior edge of the endplates. The tube is then expanded, thereby forcing the rings to expand. The rings hold their final expanded configuration via a one-way locking mechanism. Once sufficient distraction is achieved and the rings locked, the tube is collapsed and removed, thereby leaving the expanded, locked rings behind to support the disc space.

Claims

1. An intervertebral fusion device for supporting a disc space, comprising:

a) a substantially semicircular array of rings having a first unexpanded state and a second expanded, locked state,

wherein each ring in its expanded, locked state has a diameter corresponding substantially to a height of the disc space,

wherein each ring has an outer diameter, an inner diameter, and a thickness therebetween, and

wherein each ring has first and second opposed sets of gripping teeth that extend outward from the expanded ring, wherein the gripping teeth are adapted for gripping opposing endplates of vertebral bodies adjacent the disc space,

wherein the teeth point substantially perpendicularly to their respective rings in the plane of their respective ring.

2. The device of claim 1 wherein each ring has a first and second end, the first end having a first mating tooth, the second end having a second mating tooth, wherein the first and second mating teeth mate with each other in the expanded state to prevent movement of the ring to its unexpanded state.

3. The device of claim 1 wherein the plurality of rings are present in the form of a plurality of spiral coils.

4. The device of claim 3 wherein the plurality of spiral coils are nested.

5. The device of claim 3 wherein the plurality of spiral coils are made of a memory metal.