Tensioning Instrument

Patent metadata

Field	Value
Publication number	US-2016331431-A1
Application number	US-201615223939-A
Country	US
Kind code	A1
Filing date	Jul 29, 2016
Priority date	Nov 21, 2012
Publication date	Nov 17, 2016
Grant date	—

Abstract

A bone plate system for securing a plurality of bones is provided including a plate member, a locking device of the bone plate, and a surgical cable having a trailing end for being connected to the bone plate and a leading end for being advanced around the bones and into the locking device. The surgical cable may be tensioned to approximate the bones, urge the bones together, and seat the bone plate against the bones. The locking device may be reconfigured to a locked configuration to fix the bone plate to the surgical cable. The bone plate further includes a plurality of throughbores for receiving bone anchors that rigidly fix the bone plate to the bones. The bone plate system utilizes the tensile strength of the surgical cable and the rigid fixation between the bone anchors and the bone plate to resist relative movement of the bones.

First claim

What is claimed is:

1 . An instrument for tensioning a surgical cable, the instrument comprising:
a rotary tensioner operable to have surgical cable wound up thereon; a ratchet assembly that permits turning of the rotary tensioner in a wind up direction and resists turning of the rotary tensioner in a pay out direction; and a drive operably connected to the rotary tensioner and having a handle configured to be turned in a first rotary direction to cause the drive to turn the rotary tensioner in the wind up direction and wind surgical cable onto the rotary tensioner and configured to be turned in a reverse, second rotary direction to operatively disengage the drive from the ratchet assembly and permit the rotary tensioner to turn in the pay out direction.

2 . The instrument of claim 1 wherein the drive includes at least one detent member having a drive position in which the detent member operatively engages the drive and a portion of the ratchet assembly together and a release position in which the detent member allows the drive and the portion of the ratchet assembly to rotate relative to each other, and turning the handle in the second rotary direction shifts the at least one detent member from the drive position to the release position.

3 . The instrument of claim 1 wherein the drive includes a plurality of detent members and the ratchet assembly includes a plurality of cam surfaces configured to shift the detent members radially inwardly out of operative engagement with the ratchet assembly with turning of the handle in the second rotary direction.

4 . The instrument of claim 1 wherein the drive includes a first shaft connected to the handle and a second shaft connected to the rotary tensioner; and
a resilient member of the drive includes a first portion secured to the first shaft and a second portion secured to the second shaft such that the resilient member resists turning of the first shaft relative to the second shaft in response to turning of the handle in the second rotary direction.

5 . The instrument of claim 1 wherein the drive includes a first drive portion connected to the handle and a second drive portion connected to the rotary tensioner, the first and second drive portions including an elongated slot with opposite ends and a member received in the slot wherein turning the handle in the first rotary direction abuts the member against one of the ends of the slot and causes turning of the second drive portion in the first rotary direction and turning the handle in the second rotary direction causes the member to slide toward the other end of the elongated slot and permits the first drive portion to turn in the second rotary direction relative to the second drive member.

6 . The instrument of claim 1 wherein the drive includes a shaft connected to the rotary tensioner and the rotary tensioner includes a pair of members movable relative to each other to clamp a surgical cable with the shaft of the drive being integrally formed with one of the members of the rotary tensioner.

7 . The instrument of claim 1 wherein the ratchet assembly includes a ratchet gear selectively coupled to the drive, a pawl, and a biasing member urging the pawl into engagement with the ratchet gear.

8 . The instrument of claim 7 wherein the pawl remains engaged with the ratchet gear when the handle of the drive is turned in the second rotary direction to disengage the drive from the ratchet assembly.

9 . An instrument for tensioning a surgical cable, the instrument comprising:
a rotary tensioner; a handle; a drive shaft assembly connecting the handle and the rotary tensioner such that turning of the handle in a first rotary direction causes the rotary tensioner to turn in a wind up direction and turning of the handle in an opposite, second rotary direction causes the rotary tensioner to turn in a pay out direction; a ratchet assembly that is operatively engageable with the drive shaft assembly and permits turning of the drive shaft assembly in the first rotary direction and resists turning of the drive shaft assembly in the second rotary direction; a pair of shaft members of the drive shaft assembly configured to turn relative to each other with turning of the handle in the second rotary direction which operatively disengages the drive shaft assembly from the ratchet assembly and permits the drive shaft assembly to turn in the second rotary direction; and a biasing member of the drive shaft assembly secured to the shaft members that resists relative turning of the shaft members and urges the shaft assembly back into operative engagement with the ratchet assembly.

10 . The instrument of claim 9 wherein the drive shaft assembly includes a plurality of detent members and one of the shaft members urges the detent members into operative engagement with the ratchet assembly with turning of the handle in the first direction and the one shaft member permits the detent members to operatively disengage from the ratchet assembly with turning of the handle in the second rotary direction.

11 . The instrument of claim 9 wherein the drive shaft assembly includes a plurality of detent members configured to operatively engage the drive shaft assembly to the ratchet assembly wherein one of the shaft members includes openings sized to receive the detent members and the other of the shaft members includes recesses that align with the openings in response to turning of the handle in the second rotary direction.

12 . The instrument of claim 9 wherein the ratchet assembly includes a ratchet gear mounted to the drive shaft assembly and the drive shaft assembly includes detent members that extend into recesses of the ratchet gear with turning of the handle in the first direction and shift out of the recesses with turning of the handle in the second direction.

13 . The instrument of claim 9 wherein the biasing member has a straight, elongate configuration and includes a first end portion secured to one of the shaft members and a second end portion secured to the other of the shaft members.

14 . The instrument of claim 9 wherein one of the shaft members is connected to the handle and turning the handle in the second rotary direction turns the one shaft member against the bias of the biasing member.

15 . The instrument of claim 9 wherein the rotary tensioner includes a pair of gripping portions movable between a pass-through configuration that permits a surgical cable to be drawn between the gripping portions to a gripping configuration that fixes the surgical cable relative to the gripping portions for generating tension in the fixed surgical cable; and
one of the shaft members is secured to the handle and the other of the shaft members is secured to one of the gripping portions of the rotary tensioner.

16 . The instrument of claim 15 wherein the other of the shaft members is formed integrally with the one gripping portion of the rotary tensioner.

17 . An instrument for tensioning a surgical cable, the instrument comprising:
a rotary tensioner; a drive shaft connected to the rotary tensioner such that turning of the drive shaft in a first rotary direction causes the rotary tensioner to turn in a wind up direction for winding up surgical cable on the rotary tensioner; a ratchet assembly connected to the drive shaft and including a pawl and a ratchet gear configured to permit the drive shaft to be turned in the first rotary direction and resist turning of the drive shaft in an opposite, second rotary direction; at least one release member having a drive position wherein t

Assignees

• Pioneer Surgical Tech Inc

Inventors

• Gephart Matthew P

Classifications

• B60P7/0823

  Straps; Tighteners · CPC title

• A61B17/808

  Instruments for holding or positioning bone plates, or for adjusting screw-to-plate locking mechanisms · CPC title

• A61B17/8888

  at its central region · CPC title

• A61B2017/00407

  Ratchet means · CPC title

• A61B17/8057

  the interlocking form comprising a thread · CPC title