Dual-taper, asymmetric hole placement in reconstruction and fracture plates

• US 4,955,886 A
• Filed: 04/01/1988
• Issued: 09/11/1990
• Est. Priority Date: 04/01/1988
• Status: Expired due to Fees

• Current Assignee: Trustees Of Columbia University In The City Of New York (Columbia University)
• Original Assignee: Trustees Of Columbia University In The City Of New York (Columbia University)
• Inventors: Pawluk, Robert J.
• Primary Examiner(s): Hafer, Robert A.
• Assistant Examiner(s): Sam, Charles H.
• Application Number:
  US07/176,651
• Time in Patent Office: 893 Days
• Field of Search: 128/92 D, 128/92 R, 128/92 YP, 128/92 YF, 128/92 YK, 128/92 YV, 606/69, 606/88
• US Class Current: 606/280
• 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: Y10S 606/902 Cortical plate specifically adapted for a particular bone

Abstract

The invention relates to a reconstruction or fracture plate for bridging a discontinuity in a patient'"'"'s long bone, such as a femur and has a central portion for placement over the bone discontinuity, a first end portion having a dual-tapered width and thickness profile having a first plurality of screw holes and a second end portion defining a second plurality of screw holes. The first and second plurality of screw holes each have asymmetrically arrayed centerlines relative to plate longitudinal and transversal axes and the screw holes may have asymetrically arrayed centerlines relative to each other. Both the first and second end portions may have dual-tapered profiles.

Claims

1. A reconstruction or fracture plate for bridging a discontinuity in a long bone of a patient comprising:

a longitudinal axis for placement generally in alignment with a long axis of the long bone;

a transversal axis perpendicular to the longitudinal axis;

a central portion for placement over the bone discontinuity;

a first end portion for abutting placement against the long bone on one side of the bond discontinuity, the first end portion having a dual-tapered width and thickness profile for decreasing plate cross section and increasing plate flexibility along the longitudinal axis away from the central portion and the first end portion defining a first plurality of screw holes for receipt of bone screws, each hole having a central axis; and

a second end portion for abutting placement against the long bone on a second side of the bone discontinuity, defining a second plurality of screw holes for receipt of bone screws, each having a central axis;

the first and second plurality of screw holes each having a central axis pattern oriented relative to the plate longitudinal and transversal axes with plate taper and the distribution and orientation of the screw holes chosen to maintain bone screw bending strain direction and magnitude within limitations which reduce the likelihood of screw failure during the patient'"'"'s bone healing process.

2. The reconstruction or fracture plate of claim 1, wherein the first end portion has a greater number of screw holes than the second end portion.

3. The reconstruction or fracture plate of claim 2, wherein the first end portion has six (6) screw holes and the second end portion has four (4) screw holes.

4. The reconstruction or fracture plate of claim 1, wherein the second end portion has a dual-tapered width and thickness profile for decreasing plate cross section and increasing plate flexibility along the longitudinal axis away from the central portion.

5. The reconstruction or fracture plate of claim 4, wherein the first end portion has six (6) screw holes and the second end portion has four (4) screw holes.

6. The reconstruction or fracture plate of claim 1, wherein the first plurality of screw holes have an asymmetrically oriented central axis spacing pattern relative to each other.

7. The reconstruction or fracture plate of claim 1, wherein the second plurality of screw holes have an asymmetrically oriented central axis spacing pattern relative to each other.

8. A reconstruction or fracture plate for bridging a discontinuity in a long bone of a patient comprising:

a longitudinal axis for placement generally in alignment with a long axis of the long bone;

a transversal axis perpendicular to the longitudinal axis;

a central portion for placement over the bone discontinuity;

a first end portion for abutting placement against the long bone on one side of the bone discontinuity, the first end portion having dual-tapered width and thickness profile for decreasing the plate cross section and increasing plate flexibility along the longitudinal axis away from the central portion and defining six (6) screw holes for receipt of bone screws, each hole having a central axis; and

a second end portion for abutting placement against the long bone on a second side of the bone discontinuity, defining four (4) screw holes for receipt of bone screws, each having a central axis;

the screw holes on each end portion having a central axis pattern oriented relative to the plate longitudinal and transversal axes with the plate taper and the distribution and orientation of the screw holes chosen to maintain bone screw bending strain direction and magnitude within limitations which reduce the likelihood of screw failure during the patient'"'"'s bone healing process.

9. A reconstruction or fracture plate for bridging a discontinuity in a long bone of a patient comprising:

a longitudinal axis for placement generally in alignment with a long axis of the long bone;

a transversal axis perpendicular to the longitudinal axis;

a central portion for placement over the bone discontinuity;

a first end portion for abutting placement against the long bone on one side of the bone discontinuity, the first end portion having dual-tapered width and thickness profile for decreasing the plate cross section and increasing plate flexibility along the longitudinal axis away from the central portion and defining six (6) screw holes for receipt of bone screws, each hole having a central axis; and

a second end portion for abutting placement against the long bone on a second side of the bone discontinuity, the second end portion having dual-tapered width and thickness profile for decreasing the plate cross section and increasing plate flexibility along the longitudinal axis away from the central portion and defining four (4) screw holes for receipt of bone screws, each having a central axis;

each of the end portions having screw holes having a central axis pattern oriented relative to the plate longitudinal and transversal axes with the plate taper and the distribution and orientation of the screw holes chosen to maintain bone screw bending strain direction and magnitude within limitations which reduce the likelihood of screw failure during the patient'"'"'s bone healing process.