Expandable ring intervertebral fusion device

Patent metadata

Field	Value
Publication number	US-9615933-B2
Application number	US-55953709-A
Country	US
Kind code	B2
Filing date	Sep 15, 2009
Priority date	Sep 15, 2009
Publication date	Apr 11, 2017
Grant date	Apr 11, 2017

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.

First claim

We claim:

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.

Assignees

• Frasier William
• Renganathan Narendren
• Presbrey Glen
• Fisher Michael A
• Hawkins John Riley
• Depuy Synthes Products Inc

Inventors

• Frasier William
• Renganathan Narendren
• Presbrey Glen
• Fisher Michael A
• Hawkins John Riley

Classifications

• A61F2002/30594

  slotted, e.g. radial or meridian slot ending in a polar aperture, non-polar slots, horizontal or arcuate slots · CPC title

• A61F2002/30476

  locked by an additional locking mechanism · CPC title

• A61F2220/0025

  Connections or couplings between prosthetic parts, e.g. between modular parts; Connecting elements · CPC title

• A61F2210/0085

  hardenable in situ, e.g. epoxy resins · CPC title

• A61F2002/3052

  unrestrained in only one direction, e.g. moving unidirectionally · CPC title