Cervical dowel and insertion tool

• US 6,527,773 B1
• Filed: 10/10/2000
• Issued: 03/04/2003
• Est. Priority Date: 10/07/1999
• Status: Active Grant

• Current Assignee: Warsaw Orthopedic Incorporated (Medtronic Plc)
• Original Assignee: Osteotech Incorporated (Medtronic Plc)
• Inventors: Lin, Jo-Wen, Lin, Ching-Yi
• Primary Examiner(s): Reip, David O.
• Assistant Examiner(s): Woo, Julian W.
• Application Number:
  US09/685,530
• Time in Patent Office: 875 Days
• Field of Search: 606/61, 606/76, 606/77, 606/73, 606/99, 606/104, 623/17.11, 623/17.16, 623/16.11, 441/403, 441/405, 441/393, 441/402, 441/407, 441/919, 441/410, D 9/439, D12/197
• US Class Current: 606/247
• CPC Class Codes: A61F 2/28 Bones joints A61F2/30
• 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 2/4611 of spinal prostheses
• CPC Class Codes: A61F 2002/2839 Bone plugs or bone graft dowels
• CPC Class Codes: A61F 2002/30057 made from both cortical and cancellous adjacent parts
• CPC Class Codes: A61F 2002/30772 Apertures or holes, e.g. of circular cross section
• CPC Class Codes: A61F 2002/30782 inclined obliquely
• CPC Class Codes: A61F 2002/30808 parallel
• CPC Class Codes: A61F 2002/3081 inclined obliquely with respect to each other
• 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 2002/4627 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 2002/4628 with linear motion along or rotating motion about an axis transverse to the instrument axis or to the implantation direction, e.g. clamping
• CPC Class Codes: A61F 2310/00359 Bone or bony tissue

Abstract

A dowel insertion tool includes a T-shaped handle and a hollow sleeve which extends distally from the T-shaped handle. A shaft extends from the handle through the hollow sleeve and includes a transverse extension. A rotatable knob having an annular channel positioned to receive the transverse extension is supported adjacent the handle. A pin is secured to the knob and extends into a helical camming channel formed in the sleeve. Upon rotation of the knob, the pin moves within the camming channel to move the knob longitudinally about the sleeve. Movement of the knob effects longitudinal movement of the shaft. A support plate is secured to the distal end of the shaft. A pair of prongs are slidably secured to the plate. Each of the prongs includes an enlarged head portion which is slidably positioned within a slot formed in the plate. A guide member is secured to the distal end of the sleeve. The guide member includes a pair of guide bores dimensioned to receive a distal end of the prongs. The guide bores direct the prongs outwardly from the distal end of the hollow sleeve at an angle to the longitudinal axis of the sleeve. The prongs are dimensioned to be received in bores formed in the trailing end of a cervical dowel. Because the prongs engage the dowel at an angle, the dowel is both rotatably and longitudinally fixed to the insertion tool.

Claims

1. An intervertebral dowel comprising:

a cylindrical body formed from bone, the cylindrical body defining a longitudinal axis and having a first end, a second end and cylindrical sidewall;

a single throughbore formed transversely through the cylindrical sidewall; and

at least one insertion tool engaging bore formed in the first end of the cylindrical body, the at least one insertion tool engaging bore having a longitudinal axis which is oblique to the longitudinal axis of the cylindrical body.

2. An intervertebral dowel according to claim 1, wherein the throughbore is formed by an intramedullary canal of the bone from which the dowel has been cut.

3. An intervertebral dowel according to claim 1, wherein the dowel is formed from cancellous bone.

4. An intervertebral dowel according to claim 1, wherein the dowel is formed from cortical bone.

5. An intervertebral dowel according to claim 1, wherein the at least one insertion tool engaging bore includes a plurality of bores.

6. An intervertebral dowel according to claim 1, wherein the cylindrical sidewall of the dowel includes a helical thread.

7. An intervertebral dowel according to claim 1, wherein the cylindrical sidewall of the dowel includes a roughened surface.

8. An intervertebral dowel according to claim 1, wherein the at least one insertion tool engaging bore includes a pair of bores angled in a diverging direction to each other.

9. An intervertebral dowel according to claim 1, wherein the at least one insertion tool engaging bore includes a pair of bores angled in a converging direction to each other.