Dynamic bone fracture plates

Patent metadata

Field	Value
Publication number	US-8974504-B2
Application number	US-201313891839-A
Country	US
Kind code	B2
Filing date	May 10, 2013
Priority date	May 10, 2012
Publication date	Mar 10, 2015
Grant date	Mar 10, 2015

Abstract

A bone fracture plate assembly including female and male plate portions. The female plate portion has a post, a female dovetail, and an extending arm with a group of ratchet teeth. The male plate portion has two upstanding posts, a male dovetail for coupling to the female dovetail so that the plate portions move linearly with respect to each other, a slot for the arm, and a pawl for engaging the ratchet teeth. A spring, coupled to the posts of the plate portions, dynamically connects the plate portions by applying a compressive load therebetween. The spring has a pair of elongated ears, each defining a slot to allow for relative movement of the plate portions. The ratchet teeth are engaged by the pawl to retain the plate portions together, and the spring mounts on the posts of the plate portions such that the spring biases the plate portions together.

First claim

What is claimed is:

1. A bone plate assembly comprising:
a female plate portion having: a post upstanding from the female plate portion; a first end; a second end defining two apertures for fasteners; and an arm extending from the first end parallel to the female plate portion, the arm defining a plurality of ratchet teeth;
a male plate portion having: two posts upstanding from the male plate portion; a first end for coupling to the first end of the female plate portion so that the plate portions only move linearly with respect to each other and a slot for receiving the arm; a second end defining two apertures for fasteners; and a pawl for engaging the ratchet teeth; and
a spring for dynamically connecting the plate portions by applying a compressive load therebetween, the spring having: an apex portion defining a hole for coupling to the post of the female plate portion; and a pair of elongated ears extending from the apex portion, each ear defining a slot for coupling to the posts of the male plate portion, respectively,
wherein, the first end of the male plate inserts in the first end of the female plate so that the arm extends into the slot of the male plate portion and the ratchet teeth are engaged by the pawl to retain the plate portions together, and the spring mounts on the posts of the plate portions such that the spring biases the male and female plate portions together.

2. A bone plate assembly as recited in claim 1 , wherein the arm includes a first tooth on a distal end and the plurality of ratchet teeth are linearly spaced from the first tooth and the male plate portion includes a second pawl for selectively engaging the first tooth in an open position in which the male and female plate portions are held apart.

3. A bone plate assembly as recited in claim 2 , wherein the arm is deflectable so that the first tooth can be disengaged from the second pawl.

4. A bone plate assembly as recited in claim 2 , further comprising a top plate coupled to the male and female plate portions for covering the spring.

5. A bone plate assembly as recited in claim 4 , wherein the top plate defines a hole for allowing a user to deflect the arm to separate the first tooth from the second pawl so that the spring dynamically biases the male and female plate together.

6. A bone plate assembly comprising:
a) at least first and second plate segments adapted and configured for movement relative to one another from a spaced apart position and an approximated position;
b) ratchet means for allowing the first and second plate segments to move to the approximated position while preventing the first and second plate segments from moving toward a spaced apart position; and
c) a spring mechanism extending between the at least first and second plate segments to bias the at least first and second plate segments together, wherein the spring mechanism includes: an apex defining a hole for coupling to one of the plate segments; and a pair of elongated ears extend from the apex, each ear defining a slot for slidingly coupling to posts on the other plate portion, respectively, such that the elongated ears create a compression force between the plate portions that generally biases the plate portions together.

7. A bone plate assembly as recited in claim 6 , wherein the ratchet means includes a ratcheting pawl member operatively associated with the first plate segment and a rack of ratchet teeth provided on the second plate segment for interacting with the pawl member.

8. A bone plate assembly as recited in claim 6 , further comprising at least one bar coupled between the at least first and second plate segments in a sliding arrangement to act as a linear guide.

9. A bone plate assembly as recited in claim 8 , wherein the at least one bar and sliding arrangement is a male dovetail portion on the first plate segment and a complimentary female dovetail portion on the second plate segment.

10. A bone plate assembly as recited in claim 6 , further comprising:
d) a locking mechanism to lock for selectively setting a gap between the at least first and second plate segments to create a static open position and unlock to create a dynamic closed position in which the spring mechanism can draw the at least first and second plate segements together.

11. A bone plate assembly as recited in claim 6 , further comprising a top plate coupled to the plate portions for covering the spring mechanism, wherein the top plate defines a hole for allowing a surgeon disengage the ratchet means.

12. A bone plate assembly as recited in claim 6 , wherein the spring is fabricated from a memory alloy and rotationally fixed.

13. A bone plate assembly for facilitating healing of a bone fracture comprising:
a first plate portion;
a second plate portion coupled to the first plate portion so that the plates move with respect to each other linearly; and
a spring tensioning mechanism for dynamically connecting the first and second plate portions such that when mounted on opposite sides of a bone fracture, the first and second plate portions apply a compressive load to the bone fracture,
wherein
the spring mechanism includes: an apex defining a hole for coupling to one of the plate segments; and a pair of elongated ears extend from the apex, each ear defining a slot for slidingly coupling to posts on the other plate portion, respectively, such that the elongated ears create a compression force between the plate portions that generally biases the plate portions together.

Assignees

• Spinal Simplicity Llc

Inventors

• Hess Harold
• Frock Melissa
• Frock Adam
• Rogers Adam
• Moseley Todd
• Hess Jonathan
• Sand Paul
• Gonzalez Carlos

Classifications

• A61B17/7059

  Cortical plates (A61B17/7007, A61B17/7058 take precedence) · CPC title

• A61B17/8004 Primary

  with means for distracting or compressing the bone or bones · CPC title

• A61B17/8042

  the additional component being a cover over the screw head · CPC title

• A61B17/8009 Primary

  the plate having a ratchet · CPC title

• A61B17/8875

  Screwdrivers, spanners or wrenches · CPC title