Instrument for removing tabs from a reduction screw

Patent metadata

Field	Value
Publication number	US-2016346017-A1
Application number	US-201615170386-A
Country	US
Kind code	A1
Filing date	Jun 1, 2016
Priority date	Jun 1, 2015
Publication date	Dec 1, 2016
Grant date	—

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

1 . An instrument for breaking off and retaining at least one tab of a reduction screw, the instrument comprising:
a breaking arm, the breaking arm configured to hold the at least one tab; and a retaining mechanism having a tab retaining pin and a biasing member configured to urge the tab retaining pin towards the tab so as to hold the tab within the breaking arm.

2 . The instrument as set forth in claim 1 , further comprising a slide, the slide 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 breaking arm includes an elongated housing, the slide 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 4 , wherein the elongated housing includes a top wall, a pair of side walls and an elongated slot disposed on each one of the pair of side walls.

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

7 . The instrument as set forth in claim 6 , wherein the pin housing is generally a slot disposed on an inner surface of the top 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.

8 . The instrument as set forth in claim 7 , 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.

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

10 . 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 configured to hold one of the at least one tab; 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 having a tab retaining pin and a biasing member configured to urge the tab retaining pin towards the tab so as to hold the tab within each one of the pair of breaking arms.

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

12 . The instrument as set forth in claim 11 , wherein the retaining mechanism includes a slide slidably mounted to each of the pair of breaking arms, the biasing member 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.

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

14 . The instrument as set forth in claim 13 , 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.

15 . The instrument as set forth in claim 14 , 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.

16 . The instrument as set forth in claim 15 , wherein the pair of breaking arms include an elongated housing having a top wall, a pair of side walls and an elongated slot disposed on each one of the pair of side walls.

17 . The instrument as set forth in claim 16 , wherein the elongated housing includes a pin housing.

18 . The instrument as set forth in claim 17 , wherein the pin housing is generally a slot disposed on an inner surface of the top 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

• A61B2090/037

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

• A61B17/8863 Primary

  Apparatus for shaping or cutting osteosynthesis equipment by medical personnel · 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

• A61B17/7032

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

• A61B17/7091 Primary

  for applying, tightening or removing longitudinal element-to-bone anchor locking elements, e.g. caps, set screws, nuts or wedges · CPC title