Middle expandable intervertebral disk implants

• US 5,171,278 A
• Filed: 02/22/1991
• Issued: 12/15/1992
• Est. Priority Date: 02/22/1991
• Status: Expired due to Term

• Current Assignee: Perumala Corporation
• Original Assignee: Madhavan Pisharodi
• Inventors: Pisharodi, Madhavan
• Primary Examiner(s): Green, Randall L.
• Assistant Examiner(s): WILLSE, DAVID H
• Application Number:
  US07/659,758
• Time in Patent Office: 662 Days
• Field of Search: 623/17, 623/16, 623/18, 606/60, 606/61, 606/63, 128/69
• US Class Current: 128/898
• CPC Class Codes: A61F 2/30744 End caps, e.g. for closing an endoprosthetic cavity
• CPC Class Codes: A61F 2/442 Intervertebral or spinal discs, e.g. resilient non-disc-shaped intervertebral inflatable pockets A61F2/441; non-disc-shaped intervertebral fusion implants A61F2/4455
• 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 2/446 having a circular or elliptical cross-section substantially parallel to the axis of the spine, e.g. cylinders or frustocones
• CPC Class Codes: A61F 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 2002/30092 using shape memory or superelastic materials, e.g. nitinol
• CPC Class Codes: A61F 2002/30113 circular
• CPC Class Codes: A61F 2002/30143 hexagonal
• CPC Class Codes: A61F 2002/30146 octagonal
• CPC Class Codes: A61F 2002/30153 rectangular
• CPC Class Codes: A61F 2002/30154 square
• CPC Class Codes: A61F 2002/30224 cylindrical
• CPC Class Codes: A61F 2002/30225 Flat cylinders, i.e. discs
• CPC Class Codes: A61F 2002/30235 tubular, e.g. sleeves
• CPC Class Codes: A61F 2002/30261 parallelepipedal
• CPC Class Codes: A61F 2002/3028 polyhedral different from parallelepipedal and pyramidal
• CPC Class Codes: A61F 2002/30293 Cylindrical body made by spirally rolling up a sheet or a strip around itself
• CPC Class Codes: A61F 2002/30329 Connections or couplings between prosthetic parts, e.g. between modular parts; Connecting elements
• CPC Class Codes: A61F 2002/30405 made by screwing complementary threads machined on the parts themselves
• 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 2002/30471 : connected by a hinged linkage mechanism, e.g. of the single-bar or multi-bar linkage type
• CPC Class Codes: A61F 2002/30507 : using a threaded locking member, e.g. a locking screw or a set screw
• CPC Class Codes: A61F 2002/30556 : for adjusting thickness
• CPC Class Codes: A61F 2002/30573 : 2-D spiral springs
• CPC Class Codes: A61F 2002/30579 : with mechanically expandable devices, e.g. fixation devices
• 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 2002/30599 : stackable
• CPC Class Codes: A61F 2002/30624 : Hinged joint, e.g. with transverse axle restricting the movement
• CPC Class Codes: A61F 2002/30777 : Oblong apertures
• CPC Class Codes: A61F 2002/30787 : inclined obliquely with respect to each other
• CPC Class Codes: A61F 2210/0014 : using shape memory or superelastic materials, e.g. nitinol
• 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 2230/0006 : circular
• CPC Class Codes: A61F 2230/0017 : Angular shapes
• CPC Class Codes: A61F 2230/0019 : rectangular
• CPC Class Codes: A61F 2230/0021 : square
• CPC Class Codes: A61F 2230/0063 : Three-dimensional shapes
• CPC Class Codes: A61F 2230/0069 : cylindrical
• CPC Class Codes: A61F 2230/0082 : parallelepipedal
• CPC Class Codes: A61F 2230/0091 : helically-coiled or spirally-coiled, i.e. having a 2-D spiral cross-section
• CPC Class Codes: A61F 2250/0009 : for adjusting thickness
• CPC Class Codes: A61F 2250/0063 : Nested prosthetic parts
• CPC Class Codes: A61F 2310/00023 : Titanium or titanium-based alloys, e.g. Ti-Ni alloys

Abstract

Artificial disk implant and methods for implanting it, the implant having a member for adapting in size and shape to an anatomical space between vertebrae and apparatus for expanding the member to conform to the space.

Claims

1. A method of implanting an intervertebral disk unit between two vertebrae after removal of a diseased or damaged intervertebral disk from therebetween, the disk unit being cylindrical in shape and comprising a member capable of adapting to the shape of an anatomical region of said disk space and means for variably expanding said member to substantially conform the shape of said member to the shape of a portion of said disk space, comprising the steps of:

(a) inserting said disk unit into said disk space;

(b) expanding the middle of said disk unit without changing the diameter of the dimensions of the ends thereof; and

(c) introducing cancellous bone particles into said disk space and allowing said particles to fuse.

2. The method of claim 1, further comprising:

contacting an adhesive substance medially to said disk unit to close off the disk space.

3. The method of claim 1, wherein said cancellous bone particles are introduced into said disk space medial to the disk unit.

4. A method of implanting an artificial intervertebral disk unit between two vertebrae after removal of a diseased or damaged intervertebral disk, the disk comprising a rectangular member comprised of a plurality of rectangular subunits including interconnected end and intermediate subunits, capable of adapting to an anatomical region of a disk space and means for variably moving the intermediate rectangular subunits so that said implant conforms to anatomical boundaries of the disk space, comprising the steps of:

(a) inserting said disk unit into said disk space; and

(b) expanding said disk unit, wherein said means for moving the intermediate subunits includes screw means threadedly received in the end subunits.

5. The method of claim 4, further comprising:

tightening lock nut means against said screw means to prevent movement of said intermediate subunits.

6. A method of implanting an artificial intervertebral disk unit between two vertebrae after removal of a diseased or damaged intervertebral disk, the disk unit comprising a member capable of adapting to an anatomical region of a disk space and means for variably expanding said member to allow said member to substantially conform to a portion of said disk space, comprising the steps of:

(a) inserting said disk unit into said disk space;

(b) expanding said disk unit;

(c) introducing cancellous bone particles into said disk space; and

(d) contacting an adhesive substance medially to said disk unit to close off said disk space.

7. A method of implanting an intervertebral disk unit between two vertebrae after removal of a diseased or damaged intervertebral disk from therebetween, the disk unit being rectangular in shape and comprising intermediate and end subunits forming a member capable of adapting to the shape of an anatomical region of said disk space and means for variably expanding said member to substantially conform the shape of said member to the shape of a portion of said disk space, comprising the steps of:

(a) inserting said disk unit into said disk space;

(b) expanding the intermediate subunits comprising the middle of said disk unit without expanding the subunits comprising the ends thereof; and

(c) introducing cancellous bone particles into said disk space and allowing said particles to fuse.

8. The method of claim 7, wherein said cancellous bone particles are introduced into said disk space medial to the disk unit.