Variable angle locking screw

Patent metadata

Field	Value
Publication number	US-9629673-B2
Application number	US-201313921380-A
Country	US
Kind code	B2
Filing date	Jun 19, 2013
Priority date	Jan 8, 2010
Publication date	Apr 25, 2017
Grant date	Apr 25, 2017

Abstract

A method of mounting a base plate to a biologic material comprising inserting and retaining a threaded nut within a first through hole of a base plate, wherein the first hole is at least partially defined by an interior circumferential wall and the threaded nut comprises a cylindrical inner wall at least partially defining a second through hole; inserting a screw through the first and second through holes so that at least a portion of a threaded shaft extends beyond the interior circumferential wall of the base plate; rotating the screw with respect to the base plate and the threaded nut to operatively engage a head of the screw with the threaded nut; inserting the screw into a biologic substrate; and locking an angular orientation of the screw with respect to the base plate.

First claim

What is claimed is:

1. A method of mounting a base plate to an underlying biological substrate, the method comprising:
coupling a nut within a first through hole disposed in a base plate, the first through hole defining a first longitudinal axis extending the length thereof, the first through hole at least partially defined by a flange having an interior circumferential wall, the base plate including a first anti-rotation feature, and the nut comprising:
(a) a cylindrical inner wall at least partially defining a second through hole, the cylindrical inner wall being at least partially threaded, and the second through hole defining a second longitudinal axis extending the length thereof,
(b) an engaging wall extending from a first end of the nut, the engaging wall at least partially circumscribing and extending towards an opposing second end of the nut,
(c) a projection extending radially outward from the second end of the nut, the projection having a widthwise dimension greater than a diameter of the first through hole, wherein the flange is at least partially received between the engaging wall and an outer wall of the nut to couple the nut within the first through hole; and
(d) a washer having a widthwise dimension greater than the diameter of the first through hole, wherein the projection and the washer cooperate to retain at least a portion of the nut within the first through hole;
wherein the nut is selectively rotatable within the first through hole of the base plate about and between 0 degrees and a maximum angle between the first and second longitudinal axes, and wherein the nut includes a second anti-rotation feature that is engageable with the first anti-rotation feature of the base plate to inhibit rotation of the nut with respect to the base plate in a plane perpendicular to one of the first and second axes;

inserting a screw into each of the first and second through holes so that at least a portion of a shaft of the screw extends beyond the interior circumferential wall of the base plate, where at least a head of the screw is retained within the first and second through holes, wherein the shaft comprises a first threaded portion and a second threaded portion, the first threaded portion having a first diameter and the second threaded portion having a second diameter that is greater than the first diameter, the second threaded portion being located between the head and the first threaded portion, and wherein the first threaded portion is insertable at a selected angle about and between 0 degrees and a maximum angle relative to the first longitudinal axis;
advancing the shaft of the screw through the second through hole to threadably engage the second threaded portion of the shaft of the screw with the nut;
rotationally advancing the second threaded portion of the screw with respect to the nut so that the head of the screw and the engaging wall of the nut are urged into compressive engagement with the flange and secure the selected angle of the first threaded portion.

2. The method of claim 1 , wherein the maximum angle is about 15 degrees.

3. The method of claim 1 , further comprising inserting a locking ring into the first through hole of the base plate, the locking ring being engageable with a locking ring channel disposed in the interior circumferential wall subsequent to engaging the nut within the first through hole.

4. A method of mounting a base plate to an underlying biological substrate, the method comprising:
coupling a washer nut within a first through hole disposed in the base plate, the first through hole defining a first longitudinal axis extending the length thereof, the washer nut having a second through hole disposed therein defining a second longitudinal axis extending the length thereof and a circumferential recess disposed on an outer surface thereof that receives and retains at least a portion of the base plate, wherein the circumferential recess includes a projection extending radially from a second end of the nut and an engaging wall extending from a first end of the nut towards the second end of the nut, wherein the projection has a widthwise dimension that is greater than a diameter of the first through hole to retain at least a portion of the washer nut within the first through hole, wherein a flange that at least partially defines the first through hole is received between the engaging wall and an outer wall of the nut, wherein the washer nut is axially and angularly repositionable with respect to the first through hole;
inserting a screw into each of the first and second through holes so that at least a portion of a shaft of the screw extends beyond the first through hole disposed in the base plate, wherein at least a head of the screw is retained within the first and second through holes, wherein the shaft comprises a first threaded portion and a second threaded portion, the first threaded portion having a first diameter and the second threaded portion having a second diameter that is greater than the first diameter, the second threaded portion being located between the head and the first threaded portion, and wherein the first threaded portion is insertable at a selected angle about and between 0 degrees and a maximum angle with respect to the first and second longitudinal axes;
advancing the shaft of the screw with respect to the second through hole of the washer nut to thread ably engage the second threaded portion of the threaded shaft of the screw with the washer nut; and
rotationally advancing the second threaded portion with respect to the washer nut so that the head of the screw and the washer nut are urged into compressive engagement with the base plate and secure the selected angle of the first threaded portion.

5. The method of claim 4 , wherein the maximum angle is about 15 degrees.

6. The method of claim 4 , further comprising inserting a locking ring into the first through hole of the base plate, the locking ring being engageable with a locking ring channel disposed in the interior circumferential wall subsequent to engaging the nut within the first through hole.

7. The method of claim 4 , wherein rotationally advancing the second portion of the screw with respect to the nut further comprises forming a compression joint between the head of the screw and the washer nut.

8. A method of mounting a base plate to an underlying biological substrate, the method comprising:
coupling a washer nut within a first through hole disposed in the base plate, the first through hole at least partially defined by a flange having an interior circumferential wall tapered to decrease a diameter of the interior circumferential wall from a first surface towards an opposed second surface of the base plate, the washer nut defining a second through hole that is at least partially threaded, and the washer nut comprising a circumferential recess on an outer surface thereof that receives at least a portion of the flange, wherein the circumferential recess includes a projection extending radially from a second end of the nut and an engaging wall extending from a first end of the nut towards the second end of the nut, wherein the projection has a widthwise dimension that is greater than a diameter of the first through hole to retain at least a portion of the washer nut within the first through hole;
inserting a locking ring into the first through hole of the base plate, the locking ring being engageable with a locking ring channel disposed in the interior circumferential wall, and the locking ring at least partially defining a third through hole;
inserting a screw into and at least partially through each of the first, second, and third through holes so that at least a portion of a shaft of the screw extends beyond the interior circumferent

Assignees

• Biomet Mfg Llc

Inventors

• Heilman Benjamin P

Classifications

• F16B5/0275

  the screw-threaded element having at least two axially separated threaded portions (F16B5/0283 takes precedence) · CPC title

• F16B43/02

  with special provisions for engaging surfaces which are not perpendicular to a bolt axis or do not surround the bolt · CPC title

• A61B17/8685

  comprising multiple separate parts · CPC title

• A61B17/8057

  the interlocking form comprising a thread · CPC title

• A61B17/863

  with thread interrupted or changing its form along shank, other than constant taper · CPC title