Stabilization member for stabilizing bones

• US 5,041,113 A
• Filed: 07/16/1990
• Issued: 08/20/1991
• Est. Priority Date: 07/20/1989
• Status: Expired due to Term

• Current Assignee: Jurgen Harms, Lutz Biedermann
• Original Assignee: Jurgen Harms, Lutz Biedermann
• Inventors: Biedermann, Lutz, Harms, Jurgen
• Primary Examiner(s): Frinks, Ronald
• Application Number:
  US07/552,776
• Time in Patent Office: 400 Days
• Field of Search: 606/60, 606/61, 606/65, 606/66, 606/69-71, 623/16, 623/17, 128/69, 129/69
• US Class Current: 606/288
• CPC Class Codes: A61B 17/7059 Cortical plates A61B17/7007, A61B17/7058 take precedence
• 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 17/8061 specially adapted for particular bones A61B17/70 and A61B17/74 take precedence
• CPC Class Codes: A61B 17/8695 Washers surrounding screw head in plate hole A61B17/8047, between bone plate and bone A61B17/8028

Abstract

The invention refers to a stabilization member serving for fixing broken or partly cracked bones in a predetermined position during the healing process or an even longer period. The stabilization member comprises a bar having elongated holes and the bar is fastened to the bone part to be stabilized by means of screws extending through the elongated holes. It is a drawback of such conventional stabilizing members that generally the screws can not be screwed in a direction perpendicular to the bar, because the screwing direction depends on the direction and form of the bone part. It is therefore intended to modify this conventional design such that a strong connection is obtained even in case that the screw does not extend in a direction perpendicular to the bar. To this end an intermediate piece is provided for each screw and the intermediate piece has one side resting on the bar and the other side being provided with a spherical segment-shaped recess receiving the spherical segment-shaped lower portion of the screw head.

Claims

1. Stabilization member for stabilizing bones, comprising a bar having a number of elongated holes therein, screws extending through said elongated holes for fastening said bar to a bone part for stabilization thereof, the screws having a screw head formed with a convex spherical segment-shaped bottom portion, and an intermediate piece having one side plainly resting on said bar and the other side being provided with a concave spherical segment-shaped recess receiving said bottom-portion of said screws.

2. The stabilization member of claim 1, comprising a structuring or pattern provided on the facing sides of said bar and said intermediate piece.

3. The stabilization member of claim 2, wherein said structuring comprises a ribbing or corrugation extending perpendicular to the longitudinal direction of said bar.

4. The stabilization member of claim 1, wherein said bar comprises spaced weakened portions having a reduced cross-section.

5. The stabilization member of claim 1, wherein said intermediate piece comprises two adjacent spherical recesses.

6. The stabilization member of claim 1, wherein said intermediate piece has a rectangular contour or outer shape.

7. The stabilization member of claim 1, wherein said intermediate piece has a round contour or outer shape.

8. The stabilization member of claim 1, wherein said elongated holes of said bar are bevelled at the side facing said bone.

9. The stabilization member of claim 1, wherein the contour of the intermediate piece projects beyond the longitudinal sides of said bar and comprises a shoulder embracing said bar on both sides thereof.

10. The stabilization member of claim 9, wherein said intermediate piece is bevelled at the side thereof facing said bar and rounded-off at the opposite side.