Artificial intervertebral disc

• US 7,291,173 B2
• Filed: 11/03/2003
• Issued: 11/06/2007
• Est. Priority Date: 05/06/2003
• Status: Expired due to Fees

• Current Assignee: Aesculap Implant Systems LLC (Sartorius AG)
• Original Assignee: Aesculap Incorporated (Sartorius AG)
• Inventors: Richelsoph, Marc, Clift, Joseph
• Primary Examiner(s): Philogene; Pedro
• Application Number:
  US10/700,748
• Publication Number:
  US 20040225364A1
• Time in Patent Office: 1,464 Days
• Field of Search: 623 1711- 1716, 606/61
• US Class Current: 623/17.13
• 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 2002/2817 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 2002/30014 differing in elasticity, stiffness or compressibility
• CPC Class Codes: A61F 2002/302 toroidal, e.g. rings
• CPC Class Codes: A61F 2002/30332 Conically- or frustoconically-shaped protrusion and recess
• 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 2002/30426 Bayonet coupling
• CPC Class Codes: A61F 2002/30448 using adhesives
• CPC Class Codes: A61F 2002/30495 using a locking ring
• CPC Class Codes: A61F 2002/305 Snap connection
• CPC Class Codes: A61F 2002/30563 having elastic means or damping means, different from springs, e.g. including an elastomeric core or shock absorbers
• CPC Class Codes: A61F 2002/30578 having apertures, e.g. for receiving fixation screws
• CPC Class Codes: A61F 2002/30604 modular
• CPC Class Codes: A61F 2002/30616 Sets comprising a plurality of prosthetic parts of different sizes or orientations
• CPC Class Codes: A61F 2002/30649 Ball-and-socket joints
• CPC Class Codes: A61F 2002/30841 Sharp anchoring protrusions for impaction into the bone, e.g. sharp pins, spikes
• CPC Class Codes: A61F 2002/30884 Fins or wings, e.g. longitudinal wings for preventing rotation within the bone cavity
• CPC Class Codes: A61F 2002/30904 serrated profile, i.e. saw-toothed
• 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 2220/0033 : made by longitudinally pushing a protrusion into a complementary-shaped recess, e.g. held by friction fit
• CPC Class Codes: A61F 2220/005 : using adhesives
• CPC Class Codes: A61F 2250/0018 : differing in elasticity, stiffness or compressibility
• CPC Class Codes: A61F 2310/00023 : Titanium or titanium-based alloys, e.g. Ti-Ni alloys
• CPC Class Codes: A61F 2310/00029 : Cobalt-based alloys, e.g. Co-Cr alloys or Vitallium
• CPC Class Codes: A61F 2310/00179 : Ceramics or ceramic-like structures
• CPC Class Codes: A61F 2310/00796 : Coating or prosthesis-covering structure made of a phosphorus-containing compound, e.g. hydroxy(l)apatite

Abstract

An artificial intervertebral disc including housing members including spaced inner surfaces facing each other and oppositely facing outer surfaces for engaging spaced apart intervertebral surfaces; self-adjusting bearing mechanisms operatively disposed between the inner surfaces for moving relative to the housing members to adjust and compensate for vertebral disc motion; and positioning ring for controlling motion and position of the bearing mechanisms and for absorption of compressive loads. An artificial intervertebral disc including housing members having an oval recess on the inner surfaces; oval bearing mechanisms operatively disposed within the oval recess between the inner surfaces for moving relative to the housing members to adjust and compensate for vertebral disc motion; and oval positioning ring. A spring member for an artificial intervertebral disc including a substantially annular body having an axially extended bore therethrough defining a passageway.

Claims

1. An artificial intervertebral disc comprising:

housing members having spaced inner surfaces, at least one inner surface having a recess and a peripheral groove extending outwardly from the recess;

a bearing operatively disposed between the inner surfaces for moving relative to the housing members to adjust and compensate for vertebral disc motion, the bearing comprising a first bearing disc and a second bearing disc slidably engaging the first bearing disc along a bearing surface; and

a resilient flexible positioning ring surrounding the bearing for absorbing shock and centering the bearing in response to movement, the positioning ring having a body portion and an engaging member extending radially outwardly from the body portion into the peripheral groove to secure the positioning ring in at least one of the housing members.

2. The disc according to claim 1, wherein the positioning ring forms an axial bore, and the first and second bearing discs engage one another within the axial bore.

3. The disc according to claim 1, wherein the engaging member includes a generally circular flange extending outwardly from the perimeter of the positioning ring.

4. The disc according to claim 3, wherein the peripheral groove is generally circular, and the radius of the flange and radius of the groove are substantially identical.

5. The disc according to claim 1 wherein the housing members include an outer surface having a coating thereon selected from the group consisting essentially of TiN (Titanium Nitride), diamond, diamond-like materials, synthetic carbon-based materials, and chromium-based materials.

6. The disc according to claim 1, wherein the bearing is constructed from a composition selected from the group consisting essentially of metals, ceramics, and plastics.

7. The disc according to claim 1, wherein the positioning ring is made of materials selected from the group consisting essentially of rubber, silicone, polyurethane, urethane composites, plastics, polymers and elastomers.

8. The disc according to claim 1, wherein the housing members include at least one aperture for accommodating at least one bone screw.

9. An artificial intervertebral disc comprising:

housing members having spaced inner surfaces, at least one inner surface having a recess and an annular lip extending radially inwardly above the recess;

a bearing operatively disposed between the inner surfaces for moving relative to the housing members to adjust and compensate for vertebral disc motion, the bearing comprising a first bearing disc and a second bearing disc slidably engaging the first bearing disc along a bearing surface; and

a resilient flexible positioning ring surrounding the bearing for absorbing shock and centering the bearing in response to movement, the positioning ring having a body portion and an engaging member extending radially outwardly from the body portion into engagement with the annular lip to fix the axial position of the positioning ring relative to at least one of the housing members.

10. The disc according to claim 9, wherein the positioning ring forms an axial bore, and the first and second bearing discs engage one another within the axial bore.

11. The disc according to claim 9, wherein the engaging member includes a generally circular flange extending outwardly from the perimeter of the positioning ring.

12. The disc according to claim 11, wherein the peripheral groove is generally circular, and the radius of curvature of the flange and groove are substantially identical.

13. The disc according to claim 12, wherein the housing members include an outer surface having a coating thereon selected from the group consisting essentially of TiN (Titanium Nitride), diamond, diamond-like materials, synthetic carbon-based materials, and chromium-based materials.

14. The disc according to claim 9, wherein the bearing is constructed from a composition selected from the group consisting essentially of metals, ceramics, and plastics.

15. The disc according to claim 9, wherein the positioning ring is made of materials selected from the group consisting essentially of rubber, silicone, polyurethane, urethane composites, plastics, polymers and elastomers.

16. The disc according to claim 9, wherein the housing members include at least one aperture for accommodating at least one bone screw.