Method of stabilizing adjacent vertebrae with rotating, lockable, middle-expanded intervertebral disk stabilizer

• US 5,653,762 A
• Filed: 06/07/1995
• Issued: 08/05/1997
• Est. Priority Date: 03/18/1994
• Status: Expired due to Term

• Current Assignee: Perumala Corporation
• Original Assignee: Perumala Corporation
• Inventors: Pisharodi, Madhavan
• Primary Examiner(s): Prebilic, Paul B.
• Application Number:
  US08/480,791
• Time in Patent Office: 790 Days
• Field of Search: 623/17, 623/66, 606/61, 606/62, 606/63, 606/60, 606/66, 606/53, 606/73
• US Class Current: 606/86.00A
• CPC Class Codes: A61B 17/025 Joint distractors
• CPC Class Codes: A61B 2017/0256 for the spine
• CPC Class Codes: A61F 2/30965 Reinforcing the prosthesis by embedding particles or fibres during moulding or dipping
• 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 2/446 having a circular or elliptical cross-section substantially parallel to the axis of the spine, e.g. cylinders or frustocones
• CPC Class Codes: A61F 2/4603 for insertion or extraction of endoprosthetic joints or of accessories thereof
• CPC Class Codes: A61F 2/4611 of spinal prostheses
• 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 2002/30169 Pi-shaped
• CPC Class Codes: A61F 2002/30214 having tapered sections of different conicities
• CPC Class Codes: A61F 2002/30224 cylindrical
• CPC Class Codes: A61F 2002/30253 ellipsoidal or ovoid
• CPC Class Codes: A61F 2002/30286 barrel-shaped
• CPC Class Codes: A61F 2002/3037 Translation along the common longitudinal axis, e.g. piston
• CPC Class Codes: A61F 2002/30398 Sliding
• CPC Class Codes: A61F 2002/30405 made by screwing complementary threads machined on the parts themselves
• CPC Class Codes: A61F 2002/30426 Bayonet coupling
• CPC Class Codes: A61F 2002/30433 using additional screws, bolts, dowels, rivets or washers e.g. connecting screws
• CPC Class Codes: A61F 2002/30553 for adjusting a position by translation along an axis
• CPC Class Codes: A61F 2002/30579 with mechanically expandable devices, e.g. fixation devices
• CPC Class Codes: A61F 2002/30593 : hollow
• 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 2002/30777 : Oblong apertures
• CPC Class Codes: A61F 2002/30797 : internally-threaded
• CPC Class Codes: A61F 2002/3085 : with a threaded, e.g. self-tapping, bone-engaging surface, e.g. external surface
• CPC Class Codes: A61F 2002/30873 : Threadings machined on non-cylindrical external surfaces
• CPC Class Codes: A61F 2002/30879 : Ribs
• CPC Class Codes: A61F 2002/4627 : with linear motion along or rotating motion about the instrument axis or the implantation direction, e.g. telescopic, along a guiding rod, screwing inside the instrument
• CPC Class Codes: A61F 2002/4629 : connected to the endoprosthesis or implant via a threaded connection
• 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 2220/0041 : using additional screws, bolts, dowels or rivets, e.g. connecting screws
• CPC Class Codes: A61F 2230/0047 : Pi-shaped
• CPC Class Codes: A61F 2230/0063 : Three-dimensional shapes
• CPC Class Codes: A61F 2230/0067 : conical
• CPC Class Codes: A61F 2230/0069 : cylindrical
• CPC Class Codes: A61F 2230/0076 : ellipsoidal or ovoid
• CPC Class Codes: A61F 2250/0008 : for adjusting a position by translation along an axis or two perpendicular axes
• CPC Class Codes: A61F 2310/00023 : Titanium or titanium-based alloys, e.g. Ti-Ni alloys

Abstract

A method of stabilizing adjacent vertebrae is disclosed using a middle-expanded, removable disk implant. The implant is substantially rectangular in cross-sectional shape with a minimal height and a width greater than the height. The implant is detachably mounted to an applicator for insertion into the anatomical region between two adjacent vertebrae from which a portion of the intervertebral disk has been removed, and once inserted, is positioned by anterior-posterior movement in the disk space to the position in which both the expanded, larger width middle portion and the smaller diameter end portions of the implant engage the bodies of the adjacent vertebrae and the implant is then rotated to bring the sides of the rectangularly-shaped implant defining the width of the implant, with its larger dimension, into engagement with the bodies of the adjacent vertebrae. A lock is then secured to the implant to prevent further rotation thereof.

Claims

1. A method of stabilizing two adjacent vertebrae of a patient'"'"'s spine after removal of a portion of the intervertebral disk to form a disk space therebetween comprising the steps of:

providing an elongate implant with a rectangular cross section perpendicular to the elongate length thereof and a width dimension greater than the height dimension;

inserting the elongate implant into the disk space of the patient so that the height dimension of the implant is parallel to the longitudinal axis of the patient'"'"'s spine;

rotating the implant approximately 90°

in the disk space so that the width dimension is parallel to the longitudinal axis of the patient'"'"'s spine; and

securing a lock to the rotated implant to prevent rotation of the implant relative to the lock, the lock having a surface for bearing against the body of the adjacent vertebrae to prevent rotation of the implant to which the lock is secured relative to the body of the adjacent vertebrae.

2. The method of claim 1 additionally comprising mounting an applicator to one end of the implant before inserting the implant into the disk space.

3. The method of claim 2 wherein the implant is rotated by rotating the applicator.

4. The method of claim 3 additionally comprising detaching the applicator from the implant before securing the lock to the implant.

5. The method of claim 1 additionally comprising preventing movement of the implant in the disk space along the axis of rotation of the implant.