Surgical compression plate and drill guide

• US 4,493,317 A
• Filed: 11/16/1981
• Issued: 01/15/1985
• Est. Priority Date: 11/20/1980
• Status: Expired due to Term

• Current Assignee: Synthes USA LLC (Johnson & Johnson)
• Original Assignee: Synthes LP (Johnson & Johnson)
• Inventors: Klaue, Kaj
• Primary Examiner(s): FRINKS, RONALD
• Application Number:
  US06/321,602
• Time in Patent Office: 1,156 Days
• Field of Search: 128/92 D, 128/92 R, 128/92 B, 128/92 BA, 128/92 BB, 128/92 E, 128/92 EB
• US Class Current: 606/282
• CPC Class Codes: A61B 17/1728 for holes for bone plates or plate screws
• CPC Class Codes: A61B 17/8014 the extension or compression force being caused by interaction of the plate hole and the screws

Abstract

A surgical compression plate is provided which is designed to permit the insertion of bone screws at angles up to 45°. A drill guide capable of tilting to various angles, for use in connection with the novel plate is also disclosed.

Claims

1. A surgical device for the stabilization of broken bones and for use in compression osteosynthesis comprising an elongated plate having a top surface, a bottom surface for application to a bone and a plurality of elongated holes, each of said holes having surfaces along each side sloping inwardly and downwardly, the width of said holes transversely to their longitudinal axis being constant along their length and the length greater than the width by at least one third the width, there being an undercut surface on the bottom of each of said holes at both ends thereof, said holes being symmetrical about a center line across the width of the holes.

2. The device claimed in claim 1 and including a bevelled surface running longitudinally of each of said holes connecting to the top surface of the plate and to said sloping surfaces.

3. The device claimed in claim 1 wherein the sloping surfaces are cylindrical.

4. The device claimed in claim 1 wherein the sloping surfaces are compound surfaces defined by two planes intersecting in a line parallel to the longitudinal axis of the hole.

5. The device claimed in claim 1 wherein the longitudinal axis of at least one of said holes is parallel to the longitudinal axis of the plate.

6. The device claimed in claim 1 wherein the longitudinal axis of the hole is oblique with respect to the longitudinal axis of the plate.

7. The device claimed in claim 1 wherein the longitudinal axis of at least one of said holes is at a right angle to the longitudinal axis of the plate.

8. A system for the stabilization of broken bones and for use in compression osteosynthesis comprising an elongated plate having a top surface and a bottom surface for application to a bone, a plurality of elongated holes in said plate and a plurality of screws adapted to pass through said holes to engage the bone, each of said screws having a head and a shank, the portion of said shank nearest the screw head being free from threads, the length of said holes being greater than the maximum diameter of the shank of said screws by at least one-third said diameter, there being surfaces along each side of said holes to provide for sliding movement of said screws axially of said plate, and an undercut surface at the bottom of each of said holes at at least one end thereof.

9. The system claimed in claim 8 wherein the slope of the undercut surface is such as to permit insertion of a screw at an angle of 45°

.

10. The system claimed in claim 8 wherein the unthreaded portion of at least one of said screws has a diameter at least as great as the largest diameter of the threaded portion.

11. A drill guide for drilling holes in a bone said guide comprising a drill socket and a ball-shaped bearing, said socket being attached to said bearing in a position eccentric to the center of the ball.