Tensioning instrument and method

Patent metadata

Field	Value
Publication number	US-8984720-B2
Application number	US-201213730597-A
Country	US
Kind code	B2
Filing date	Dec 28, 2012
Priority date	Dec 28, 2011
Publication date	Mar 24, 2015
Grant date	Mar 24, 2015

Abstract

In one aspect, a tensioning instrument for a securing device, such as surgical cable, is provided having a pretensioning mechanism configured to allow a predetermined preload tension to be applied to the cable and a tensioning mechanism operable to increase the tension in the cable by predetermined amount in excess of the preload tension applied by the pretensioning ,mechanism. The tensioning device has a first actuator operatively coupled to the pretensioning mechanism and is configured permit a predetermined preload tension to be applied to the cable. The tensioning device also has a second actuator different than the first actuator which is operatively coupled to the tensioning mechanism. The second actuator may be moved between an open position and a locked position to cause the tensioning mechanism to increase the tension in the cable by the predetermined amount in excess of the preload tension, if any.

First claim

What is claimed is:

1. A tensioning instrument for tensioning a cable, the tensioning instrument comprising:
a pretensioner including a pretensioner actuator operable to be shifted for setting a selected level of tension for being applied to either an untensioned or tensioned cable; and
a tensioner including a tensioner actuator different from the pretensioner actuator and being operable to be shifted between unlocked and locked positions to cause the tensioner to apply the selected level of tension set by the pretensioner and to apply a predetermined amount of tension to the cable irrespective of the selected level of tension set by the pretensioner so that shifting the tensioner actuator from the unlocked position to the locked position causes the tensioner to increase the tension in the cable to the sum of the selected level of tension and the predetermined amount of tension.

2. The tensioning instrument of claim 1 wherein the tensioner actuator includes an elongate lever pivotal between the unlocked and locked positions.

3. The tensioning instrument of claim 1 wherein the pretensioner actuator is movable between a first position where the selected level of tension is a nominal amount and a second position where the selected tension is greater than the nominal amount and, with the tensioner actuator in the locked position and the cable tensioned, the pretensioner actuator is operable to increase the tension in the cable by movement of the pretensioner actuator toward the second position.

4. The tensioning instrument of claim 1 wherein the tensioning instrument has a longitudinal axis and the pretensioner actuator is rotatable about the longitudinal axis to move the pretensioner actuator between an initial position and a preloading position to increase the selected level of tension for being applied to the cable.

5. The tensioning instrument of claim 4 wherein the tensioner actuator is pivotal about a pivot axis extending transverse to the longitudinal axis of the tensioning instrument.

6. The tensioning instrument of claim 1 wherein the tensioner includes a biasing member that is compressed with movement of the tensioner actuator between the unlocked and locked positions and the pretensioner actuator is configured to compress the biasing member with shifting of the pretensioner actuator between initial and preloading positions thereof.

7. A tensioning instrument for tensioning a cable, the tensioning instrument comprising:
a pretensioning mechanism configured to allow a predetermined preload tension to be applied to the cable;
a tensioning mechanism operable to increase the tension in cable by a predetermined amount in excess of the preload tension applied by the pretensioning mechanism;
a first actuator operatively coupled to the pretensioning mechanism and configured to be moved between an initial position where the predetermined preload tension applied to the cable by the pretensioning mechanism is a nominal amount and a preloading position where the predetermined preloading tension applied by the pretensioning mechanism is greater than the nominal amount;
a second actuator different from the first actuator that is operatively coupled to the tensioning mechanism and movable between an open position and a locked position to cause the tensioning mechanism to increase the tension in the cable by the predetermined amount in excess of the preload tension;
wherein the tensioning mechanism comprises an over-center lock connected to the second actuator, the over-center lock being configured so that movement of the second actuator to the locked position shifts the lock beyond center and restricts the tensioning mechanism from releasing tension in the cable.

8. A tensioning instrument for tensioning a cable, the tensioning instrument comprising:
a pretensioning mechanism configured to allow a predetermined preload tension to be applied to the cable;
a tensioning mechanism operable to increase the tension in cable by a predetermined amount in excess of the preload tension applied by the pretensioning mechanism;
a first actuator operatively coupled to the pretensioning mechanism and configured to be moved between an initial position where the predetermined preload tension applied to the cable by the pretensioning mechanism is a nominal amount and a preloading position where the predetermined preloading tension applied by the pretensioning mechanism is greater than the nominal amount;
a second actuator different from the first actuator that is operatively coupled to the tensioning mechanism and movable between an open position and a locked position to cause the tensioning mechanism to increase the tension in the cable by the predetermined amount in excess of the preload tension;
wherein the tensioning mechanism includes a locking device having an unlocked configuration that permits the cable to be connected to the locking device and a locked configuration which fixes the cable to the locking device.

9. A tensioning instrument comprising:
a body assembly having a distal end portion and a proximal end portion, the body assembly having a longitudinal axis extending between the distal and proximal end portions;
a guide of the body assembly adjacent the distal end portion;
a support of the body assembly slidably movable along the axis;
a biasing member between the guide and the support, the biasing member configured to bias the support away from the guide along the longitudinal axis of the body assembly;
a locking mechanism carried on the support and axially movable relative to the support, the locking mechanism having an unlocked configuration which permits a cable to be connected to the locking mechanism and a locked configuration which fixes the cable to the locking mechanism;
an actuator connected to the locking mechanism and pivotal relative to the support between an open position and a locked position; and
engagement surfaces of the actuator and support configured to engage with pivoting of the actuator between the open and locked positions and shift the support axially and distally toward the guide which compresses the biasing member and applies a tensioning force to the cable when the locking mechanism is fixed to the cable.

10. The tensioning instrument of claim 9 wherein the engagement surfaces of the actuator and guide include a curved cam surface and a generally straight follower surface extending obliquely to the longitudinal axis of the body assembly.

11. The tensioning instrument of claim 9 wherein the actuator is rigidly connected to the locking mechanism; and
a pivot connection between the locking mechanism and the support which permits the locking mechanism to pivot relative to the support with pivoting of the actuator between the open and locked positions.

12. The tensioning instrument of claim 11 wherein the locking mechanism has an aperture sized to receive the cable and is aligned with the longitudinal axis of the body assembly with the actuator in the open position and pivoting of the actuator between the open and locked positions pivots the locking mechanism aperture out of alignment with the longitudinal axis and fixes the locking mechanism to the cable.

13. The tensioning instrument of claim 9 further comprising a pretensioner assembly connected to the support and having a seat engaged with the biasing member, the pretensioner assembly being axially shiftable along the support such that shifting the pretensioner assembly toward the guide compresses the biasing member.

14. The tensioning instrument of claim 9 wherein the actuator has a base portion connected to the locking mechanism and an engagement po

Assignees

• Pioneer Surgical Tech Inc

Inventors

• Gephart Matthew P

Classifications

• A61B17/8861 Primary

  Apparatus for manipulating flexible wires or straps (devices for inserting Kirschner wires A61B17/1697) · CPC title

• A61B17/8869 Primary

  Tensioning devices · CPC title

• Y10T24/39

  Cord and rope holders · CPC title

• Y10T24/394

  Cam lever · CPC title

• Y10T24/3938

  Lever tension · CPC title