Instrument for removing tabs from a reduction screw

Patent metadata

Field	Value
Publication number	US-9968394-B2
Application number	US-201615170386-A
Country	US
Kind code	B2
Filing date	Jun 1, 2016
Priority date	Jun 1, 2015
Publication date	May 15, 2018
Grant date	May 15, 2018

Abstract

An instrument for breaking off and retaining the tab of a reduction screw is provided. The instrument includes a breaking arm and a retaining mechanism. The breaking arm is configured to break off an excess portion of the tab of the reduction screw about a weakened section. The retaining mechanism is configured to retain the broken off tab and preventing the tab from falling into a surgical site. The retaining mechanism is further configured to allow the instrument to engage another tab while simultaneously holding a predetermined number of previously broken off tabs. Accordingly, the instrument reduces surgical time as the surgeon may simply move from one reduction screw to another while breaking off the tabs until the instrument can no longer retain additional broken off tabs.

First claim

The invention claimed is:

1. An instrument for breaking off and retaining at least one tab of a reduction screw, the instrument comprising:
a breaking arm comprising a back wall, a pair of sidewalls extending from the back wall, and a pair of inner ledges spaced apart from the back wall extending from the pair of sidewalls along an axial length of the breaking arm and forming an elongated housing for receiving at least one tab of the reduction screw, the breaking arm configured to hold the at least one tab; and
a retaining mechanism comprising a slide with a tab retaining pin and a biasing member configured to urge the tab retaining pin against the tab so as to retain a broken off tab within the elongated housing of the breaking arm.

2. The instrument as set forth in claim 1 , a slide, wherein the slide is fixedly mounted to the tab retaining pin and operatively engaged with the biasing member.

3. The instrument as set forth in claim 2 , wherein the slide is slidably mounted to the elongated housing.

4. The instrument as set forth in claim 3 , wherein the elongated housing includes a block member, the biasing member disposed between the block member and the slide.

5. The instrument as set forth in claim 1 , wherein the elongated housing includes a pin housing.

6. The instrument as set forth in claim 5 , wherein the pin housing is generally a slot disposed on an inner surface of the back wall of the elongated housing and transversing a width of the breaking arm, wherein the pin housing is in open communication with a proximal end of the elongated slot.

7. The instrument as set forth in claim 6 , wherein the slide includes a spring support fixedly mounted to the slide and the biasing member is disposed between the spring support and the block member.

8. The instrument as set forth in claim 1 , further comprising a handle mounted to a proximal end of the breaking arm.

9. An instrument for breaking off and retaining at least one tab of a reduction screw, the instrument comprising:
a pair of breaking arms, each of the pair of breaking arms comprising a back wall, a pair of sidewalls extending from the back wall, and a pair of inner ledges spaced apart from the back wall extending from the pair of sidewalls along an axial length of the breaking arm and forming an elongated housing for receiving at least one tab of the reduction screw;
a drive shaft;
a pair of pivot arms, each of the pair of pivot arms rotatably mounted to the drive shaft and a respective one of the pair of breaking arms, the drive shaft configured to advance axially between the pair of breaking arms so as to radially displace each of the pair of pivot arms away from each other and breaking the tab off of the reduction screw; and
a retaining mechanism comprising a slide with a tab retaining pin and a biasing member configured to urge the tab retaining pin against the tab so as to retain a broken off tab within the elongated housing of each one of the pair of breaking arms.

10. The instrument as set forth in claim 9 , further comprising a carrier configured to guide the drive shaft along an axis.

11. The instrument as set forth in claim 10 , wherein the biasing member is operatively attached to the slide so as to urge the tab retaining pin to continuously engage the tab, wherein actuation of the slide disengages the tab retaining pin from the tab so as to release the tab from the respective breaking arm.

12. The instrument as set forth in claim 11 , wherein the carrier includes a through hole, the drive shaft mounted within the through hole.

13. The instrument as set forth in claim 12 , wherein the carrier includes a first slot, the first slot having a length extending along the length of the carrier, the drive shaft having a drive shaft pin extending radially from the drive shaft, the drive shaft pin disposed within the first slot.

14. The instrument as set forth in claim 13 , further comprising a second biasing member and a head portion, wherein the second biasing member is disposed on a distal end of the drive shaft and urges the head portion distally so as to place the pair of breaking arms into a closed position.

15. The instrument as set forth in claim 9 , wherein the elongated housing includes a pin housing.

16. The instrument as set forth in claim 15 , wherein the pin housing is generally a slot disposed on an inner surface of the back wall and transversing a width of the breaking arm, wherein the pin housing is in open communication with a proximal end of the elongated slot.

17. An instrument for breaking off and retaining at least one tab of a reduction screw, the instrument comprising:
a back wall, a pair of sidewalls extending from the back wall, and a pair of inner ledges spaced apart from the back wall extending from the pair of sidewalls along an axial length of the breaking arm and forming an elongated housing for receiving at least one tab of the reduction screw;
a drive shaft;
a pair of pivot arms, each of the pair of pivot arms rotatably mounted to the drive shaft and a respective one of the pair of breaking arms, the drive shaft configured to advance axially between the pair of breaking arms so as to radially displace each of the pair of pivot arms away from each other and breaking the tab off of the reduction screw; and
a retaining mechanism comprising a slide with a tab retaining pin, a first biasing member configured to urge the tab retaining pin against the tab so as to retain a broken off tab within the elongated housing of each one of the pair of breaking arms, a second biasing member and a head portion, wherein the second biasing member is disposed on a distal end of the drive shaft and urges the head portion distally so as to place the pair of breaking arms into a closed position.

18. The instrument as set forth in claim 17 , wherein the pin housing is generally a slot disposed on an inner surface of the back wall and transversing a width of the breaking arm, wherein the pin housing is in open communication with a proximal end of the elongated slot.

Assignees

• Alphatec Spine Inc

Inventors

• Meyer Nathan
• Torres Eller

Classifications

• A61B17/8863 Primary

  Apparatus for shaping or cutting osteosynthesis equipment by medical personnel · CPC title

• A61B2090/037

  with a frangible part, e.g. by reduced diameter · CPC title

• A61B17/7032

  Screws or hooks with U-shaped head or back through which longitudinal rods pass · CPC title

• A61B17/7074

  Tools specially adapted for spinal fixation operations other than for bone removal or filler handling (A61B17/7062, A61B17/808, A61B17/8858 take precedence; for spinal image producing devices A61B90/36, A61B34/20; markers A61B90/39) · CPC title