Fixation system with multidirectional stabilization pegs

• US 20040260293A1
• Filed: 07/23/2004
• Published: 12/23/2004
• Est. Priority Date: 02/01/2000
• Status: Abandoned Application

• Current Assignee: Depuy Products Incorporated (Johnson & Johnson)
• Original Assignee: Hand Innovations LLC (Johnson & Johnson)
• Inventors: Orbay, Jorge L., Steffen, Dennis L., Leone, James
• Application Number:
  US10/897,922
• Publication Number:
  US 20040260293A1
• Time in Patent Office: Days
• US Class Current: 606/287
• CPC Class Codes: A61B 17/1728 for holes for bone plates or plate screws
• CPC Class Codes: A61B 17/1782 for the hand or wrist
• CPC Class Codes: A61B 17/68 Internal fixation devices , including fasteners and spinal fixators, even if a part thereof projects from the skin bone staples A61B17/0642
• CPC Class Codes: A61B 17/7208 Flexible pins, e.g. ENDER pins
• CPC Class Codes: A61B 17/80 Cortical plates , i.e. bone plates; Instruments for holding or positioning cortical plates, or for compressing bones attached to cortical plates
• CPC Class Codes: A61B 17/8033 having indirect contact with screw heads, or having contact with screw heads maintained with the aid of additional components, e.g. nuts, wedges or head covers
• CPC Class Codes: A61B 17/8038 the additional component being inserted in the screw head
• CPC Class Codes: A61B 17/8042 the additional component being a cover over the screw head
• CPC Class Codes: A61B 17/8047 wherein the additional element surrounds the screw head in the plate hole A61B17/8052 takes precedence
• CPC Class Codes: A61B 17/8052 immobilised relative to screws by interlocking form of the heads and plate holes, e.g. conical or threaded
• CPC Class Codes: A61B 17/8061 specially adapted for particular bones A61B17/70 and A61B17/74 take precedence
• CPC Class Codes: A61B 17/84 Fasteners therefor or fasteners being internal fixation devices
• CPC Class Codes: A61B 17/863 with thread interrupted or changing its form along shank, other than constant taper

Abstract

A fixation system includes a plate intended to be positioned against a bone, a plurality of bone screws for securing the plate along an non-fractured portion of the bone, and a plurality of bone pegs which extend from the plate and into bone fragments of the fracture to provide a supporting framework. The pegs can be oriented at various angles relative to an axis normal to the lower surface of the plate. For each peg, once the peg has been appropriately positioned within the peg hole, a set screw is threaded into the peg hole and tightened, thereby securing the peg in the selected orientation.

Claims

1. A fracture fixation system, comprising:

a) a substantially rigid plate having a plurality of peg holes adapted to individually receive fixation pegs therein, said peg holes having an upper portion and a lower portion, said upper portion having a first internal thread, and said lower portion having a radius of curvature;

b) a plurality of pegs each having a head and a shaft, said shaft sized to be received through said peg holes, and said head having a lower surface with substantially a same radius of curvature as said lower portion of said peg holes; and

c) a plurality of set screws each having a body including a second thread rotationally engageable with said first thread, and a proximal rotational engagement means for permitting a rotational force to be applied to said set screw,

wherein when said pegs are provided into respective peg holes, each said peg may be positioned at a plurality of angles relative to an axis normal to a lower surface of a portion of said plate surrounding a respective peg hole, and once so positioned, respective set screws when threaded into said upper portions of said peg holes fix said pegs at their respective angles.

2. A fracture fixation system according to claim 1, wherein:

when said pegs are fixed at their respective angles, said pegs are adapted to provide a framework for supporting fractured bone fragments, said pegs of said framework defining a plurality of non-parallel axes.

3. A fracture fixation system according to claim 1, wherein:

said peg holes are closely spaced in a linear or curvilinear arrangement.

4. A fracture fixation system according to claim 1, wherein:

said fixation plate has a body portion and a head portion angled relative said body portion.

5. A fracture fixation system according to claim 4, wherein:

said body portion and said head portion are configured in a T-shape.

6. A fracture fixation system according to claim 1, wherein:

said body portion includes at least one non-threaded screw hole.

7. A fracture fixation system according to claim 1, wherein:

said lower portion of said peg hole has a spherical radius of curvature.

8. A fracture fixation system according to claim 1, wherein:

said lower portion of each of said peg holes defines a surface having a relatively high coefficient of friction.

9. A fracture fixation system according to claim 1, wherein:

said outer surface of said head of each of said pegs has a surface having a relatively high coefficient of friction.

10. A fracture fixation system according to claim 1, wherein:

said plurality of angles is any angle within a predefined range of angles.

36. A fracture fixation system according to claim 1, wherein:

said shaft of at least one of said pegs is non-threaded.

11-30. -30 (canceled)

31. A fracture fixation system, comprising:

a) a substantially rigid T-shaped plate having a body portion and a head portion angled relative to said body portion, said head portion defining a plurality of peg holes adapted to individually receive fixation pegs therein;

b) a plurality of pegs each having a head portion and a shaft portion, said shaft portion sized to be received through said peg holes, and said head portion defining a ball portion having an outer surface and a substantially spherical radius of curvature, an axial threaded bore, and at least one radial slot extending from said outer surface into said threaded bore; and

c) a plurality of set screws each having a body including a outer thread sized to be rotationally engageable with said threaded bore of said head portion of said peg but causing said ball portion to increase in diameter as said set screw is rotated therein, and a proximal rotational engagement means for permitting a rotational force to be applied to said set screw,

wherein when said pegs are provided into respective peg holes, each said peg may be positioned at a plurality of angles relative to an axis normal to a lower surface of said plate, and once so positioned, respective set screws when threaded into said upper bores of said head portions of said pegs expand said head portions at said respective at least one slot and clamp said head portions between said set screws and said plate and thereby fix said pegs at their respective angles.

32. A fracture fixation system according to claim 31, wherein:

said peg holes are each provided with substantially a same substantially spherical radius of curvature as said ball portion of each said peg.

33. A fracture fixation system according to claim 31, wherein:

said peg holes are non-threaded.

34-35. -35. (canceled)