Artificial intervertebral disc having a flexible wire mesh vertebral body contact element

• US 20030069642A1
• Filed: 05/07/2002
• Published: 04/10/2003
• Est. Priority Date: 10/04/2001
• Status: Abandoned Application

• Current Assignee: Howmedica Osteonics Corp. (Stryker Corporation)
• Original Assignee: Howmedica Osteonics Corp. (Stryker Corporation)
• Inventors: Ralph, James D., Tatar, Stephen
• Application Number:
  US10/140,153
• Publication Number:
  US 20030069642A1
• Time in Patent Office: Days
• US Class Current: 623/17.13
• CPC Class Codes: A61F 2/30742 Bellows or hose-like seals; Sealing membranes A61B17/8808 takes precedence; sealing membranes for retaining bone substitute A61F2/2846
• CPC Class Codes: A61F 2/30767 Special external or bone-contacting surface, e.g. coating for improving bone ingrowth
• CPC Class Codes: A61F 2/4425 made of articulated components
• CPC Class Codes: A61F 2002/30171 rosette- or star-shaped
• CPC Class Codes: A61F 2002/302 toroidal, e.g. rings
• CPC Class Codes: A61F 2002/30433 using additional screws, bolts, dowels, rivets or washers e.g. connecting screws
• CPC Class Codes: A61F 2002/30451 soldered or brazed or welded
• CPC Class Codes: A61F 2002/30492 using a locking pin
• CPC Class Codes: A61F 2002/305 Snap connection
• CPC Class Codes: A61F 2002/30518 with possibility of relative movement between the prosthetic parts
• CPC Class Codes: A61F 2002/30565 having spring elements
• CPC Class Codes: A61F 2002/30571 Leaf springs
• 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 2002/30604 modular
• CPC Class Codes: A61F 2002/30769 madreporic
• CPC Class Codes: A61F 2002/30774 internally-threaded
• CPC Class Codes: A61F 2002/30909 Nets
• CPC Class Codes: A61F 2002/3092 having an open-celled or open-pored structure
• CPC Class Codes: A61F 2002/30975 made of two halves
• CPC Class Codes: A61F 2002/443 having two transversal endplates and at least one intermediate component
• CPC Class Codes: A61F 2220/0025 : Connections or couplings between prosthetic parts, e.g. between modular parts; Connecting elements
• CPC Class Codes: A61F 2220/0041 : using additional screws, bolts, dowels or rivets, e.g. connecting screws
• CPC Class Codes: A61F 2220/0058 : soldered or brazed or welded
• CPC Class Codes: A61F 2230/005 : Rosette-shaped, e.g. star-shaped
• CPC Class Codes: A61F 2230/0065 : toroidal, e.g. ring-shaped, doughnut-shaped
• CPC Class Codes: A61F 2310/00017 : Iron- or Fe-based alloys, e.g. stainless steel
• CPC Class Codes: A61F 2310/00023 : Titanium or titanium-based alloys, e.g. Ti-Ni alloys
• CPC Class Codes: A61F 2310/00365 : Proteins; Polypeptides; Degradation products thereof

Abstract

An artificial intervertebral disc having a pair of opposing plate members for seating against opposing vertebral bone surfaces, separated by a spring mechanism. The preferred spring mechanism is at least one spirally slotted belleville washer having radially extending grooves. The preferred attachment device for securing each plate member to a vertebral bone surface is a convex metal mesh that is laser welded at its perimeter to the plate member. The metal mesh deflects as necessary during insertion of the artificial intervertebral disc between vertebral bodies, and, once the artificial intervertebral disc is seated between the vertebral bodies, deforms as necessary under anatomical loads to reshape itself to the concave surface of the vertebral endplate. The metal mesh therefore provides superior gripping and holding strength upon initial implantation and an osteoconductive surface through which the vertebral bone may ultimately grow.

Claims

1. An artificial intervertebral disc having an osteoinductive securing surface element, the artificial intervertebral disc comprising

first and second support members, each having an outer surface,

the first and second support members being movable relative to one another and being disposed such that the outer surfaces face away from one another,

each outer surface having disposed thereon a vertebral body contact element for securably mating with a concave surface of an adjacent vertebral body endplate,

said vertebral body contact element including a flexible wire mesh,

said flexible wire mesh being deformably reshapable under anatomical loads such that said flexible wire mesh conformably deflects within said concave surface to securably engage said vertebral body endplate.

2. The artificial intervertebral disc of claim 1, wherein the wire mesh has a resting shape in the shape of a dome convexly extending from the respective support member.

3. The artificial intervertebral disc of claim 1, wherein the wire mesh is laser-welded to the respective support member.

4. The artificial intervertebral disc of claim 1, wherein the wire mesh comprises titanium.

5. The artificial intervertebral disc of claim 1, further comprising an osteoinductive feature adjacent the flexible wire mesh.

6. The artificial intervertebral disc of claim 5, where the osteoinductive feature adjacent the flexible wire mesh comprises a porous coating on the respective support member.