Instrument for use in surgery
An instrument for use in surgery includes a hollow shaft connectable to a drive shaft of a bone anchor insertion device in a rotationally fixed manner, a needle holder configured to hold a needle and movable axially relative to the hollow shaft, an actuator rotatable relative to the hollow shaft, and a transmission member connectable to the needle holder and movable axially relative to the actuator. The transmission member is positionable around at least part of the hollow shaft and includes a first advancement surface engageable with a second advancement surface of the hollow shaft to convert a rotational movement of the actuator into axial movement of the needle holder relative to the hollow shaft for axially advancing and retracting the needle held by the needle holder.
1 . An instrument for use in surgery, the instrument being connectable to a bone anchor insertion device that comprises a drive shaft configured to engage a bone anchor, the drive shaft defining a coaxial channel for receiving a needle therethrough, the instrument comprising:
a hollow shaft connectable to the drive shaft along a central axis in a rotationally fixed manner;
a needle holder configured to hold a needle and movable axially relative to the hollow shaft;
an actuator movable relative to the hollow shaft; and
a transmission member connectable to the needle holder and movable axially relative to the actuator for axially advancing and retracting the needle held by the needle holder relative to the hollow shaft, wherein the transmission member comprises a first advancement surface directed at least partially radially inwardly towards the central axis that is engageable with a second advancement surface of the instrument.
2 . The instrument of claim 1 , wherein the needle holder is positionable at least partially within the hollow shaft and is movable along the central axis relative to the hollow shaft.
3 . The instrument of claim 1 , wherein the transmission member comprises at least one projection that is configured to extend through a recess in the hollow shaft to engage the needle holder.
4 . The instrument of claim 1 , wherein the first advancement surface is provided at an inner surface of the transmission member and the second advancement surface is provided at an outer surface of the hollow shaft.
5 . The instrument of claim 1 , further comprising a handle connectable to the hollow shaft to transmit torque to the hollow shaft.
6 . The instrument of claim 5 , wherein a portion of the actuator is configured to extend axially into the handle.
7 . The instrument of claim 1 , wherein the needle holder is configured to releasably receive the needle without disassembling the instrument.
8 . The instrument of claim 1 , wherein the actuator is rotatable relative to the hollow shaft.
9 . The instrument of claim 1 , wherein the transmission member is movable relative to the needle holder.
10 . The instrument of claim 9 , wherein the transmission member is rotatable relative to the needle holder.
11 . The instrument of claim 1 , wherein the first advancement surface of the transmission member is configured to remain spaced apart from the actuator.
12 . An instrument for use in surgery, the instrument being connectable to a bone anchor insertion device that comprises a drive shaft configured to engage a bone anchor, the drive shaft defining a coaxial channel for receiving a needle therethrough, the instrument comprising:
a hollow shaft connectable to the drive shaft in a rotationally fixed manner;
a needle holder configured to hold a needle and movable axially relative to the hollow shaft;
an actuator movable relative to the hollow shaft; and
a transmission member connectable to the needle holder and movable axially relative to the actuator, wherein the transmission member comprises a first advancement surface engageable with a second advancement surface of the hollow shaft for axially advancing and retracting the needle held by the needle holder relative to the hollow shaft, and a position indicator visible from outside the instrument through a window formed in a part of the instrument different from the transmission member to indicate a relative position of the needle holder relative to the hollow shaft.
13 . The instrument of claim 12 , wherein the actuator is rotatable relative to the hollow shaft.
14 . The instrument of claim 12 , further comprising a handle connectable to the hollow shaft to transmit torque to the hollow shaft.
15 . The instrument of claim 14 , wherein the window is formed in the handle.
16 . The instrument of claim 12 , wherein at least part of the transmission member is positionable in at least part of the actuator.
17 . The instrument of claim 16 , wherein the position indicator is ring-shaped and is positionable around part of the actuator.
18 . An instrument for use in surgery, the instrument being connectable to a bone anchor insertion device that comprises a drive shaft configured to engage a bone anchor, the drive shaft defining a coaxial channel for receiving a needle therethrough, the instrument comprising:
a hollow shaft defining a recess configured to receive and end of the drive shaft to connect the hollow shaft to the drive shaft in a rotationally fixed manner;
a needle holder configured to hold a needle and movable axially relative to the hollow shaft;
an actuator movable relative to the hollow shaft; and
a transmission member connectable to the needle holder and movable axially relative to the actuator, wherein the transmission member comprises a first advancement surface engageable with a second advancement surface of the instrument for axially advancing and retracting the needle held by the needle holder relative to the hollow shaft;
wherein the recess of the hollow shaft extends axially into the actuator, such that at least part of the recess is configured to be located at a same axial position as at least part of the actuator to reduce an overall axial length of the instrument.
19 . The instrument of claim 18 , wherein the actuator is rotatable relative to the hollow shaft.
20 . The instrument of claim 18 , further comprising a separate connector configured to facilitate insertion and fixation of the drive shaft into the recess of the hollow shaft, wherein at least part of the connector is configured to extend axially into the actuator.