Bone screw and self-retaining driver

Patent metadata

Field	Value
Publication number	US-9387025-B2
Application number	US-201213439099-A
Country	US
Kind code	B2
Filing date	Apr 4, 2012
Priority date	Apr 4, 2012
Publication date	Jul 12, 2016
Grant date	Jul 12, 2016

Abstract

Techniques disclosed herein include systems and methods for a bone screw and self-retaining driver. The system includes a mechanism that enables a bone screw to be rigidly attached to a screwdriver for manipulation and transfer of bone fragments and grafts to a fixation site, such as during surgery. The system includes a cannulated bone screw that has a drive connection that engages with a drive structures of a screwdriver. The bone screw also includes a structural connector that securely attaches to or receives an internal shaft or rod of the screwdriver. The internal shaft or rod of the screwdriver can rotate and slide independent of an outer shaft of screwdriver. Accordingly, the internal shaft of the screwdriver can rigidly connect with the bone screw enabling applied torque to the screwdriver to be transferred to the bone screw, without the bone screw falling off of the drive connection.

First claim

The invention claimed is:

1. A bone screw and self-retaining driver system comprising:
a bone screw, the bone screw comprising:
an elongated member comprising a head and a shaft extending distally from the head, the shaft further having a distal end, a proximal end, and a longitudinal axis,
at least a portion of the distal end of the shaft having external threading adapted to advance the bone screw into bone media,
the head defining a flange radially enlarged relative to the shaft of the bone screw, said flange having a proximal surface and a distal surface opposite to the proximal surface, the proximal surface comprising at least one recess defined by axial protrusions extending from the proximal surface configured to receive applied torque, and wherein the distal surface is concave relative to a peripheral annular edge of the distal surface;
the bone screw being cannulated by defining a passage that follows the longitudinal axis of the bone screw, the defined passage sized to enable the bone screw to travel along a guide wire,
the head and at least a portion of the proximal end of the shaft defining a socket having internal threading, the defined socket aligned with the defined passage; and

a bone screwdriver, the bone screwdriver comprising:
a handle portion;
a shaft portion connected to the handle portion, the shaft portion including an external shaft and an internal shaft, wherein the internal shaft is positioned within the external shaft, and wherein the internal shaft is configured to rotate independent of the external shaft,
at least one projection formed at a distal end of the external shaft, the at least one projection configured to transfer applied torque to the at least one recess of the head of the bone screw when in contact with the at least one projection,
an external threading formed at a distal end of the internal shaft, the external threading adapted to advance into the defined socket of the bone screw such that, when advanced into the internal threading of the defined socket, the bone screw is securely attached to the bone screwdriver via the internal shaft and the at least one projection of the external shaft is in contact with the at least one recess of the head of the bone screw,
a rotatable wheel that controls rotation of the internal shaft independent of the external shaft, wherein the rotatable wheel is secured within the handle portion at a longitudinal position distally offset from a proximal end of the handle portion and wherein the rotatable wheel is independent from the inner shaft,
the bone screwdriver being cannulated by defining a passage that follows a longitudinal axis of the bone screwdriver such that the bone screwdriver can travel along a guide wire;
wherein the rotatable wheel is framed within an opening defined within the handle portion and is configured to slide longitudinally within the handle, causing the internal shaft to travel longitudinally within the external shaft, and
wherein a longitudinal travel of the rotatable wheel is sufficient for the internal shaft to retract within the external shaft and to extend from the external shaft to couple with the defined socket.

2. The bone screw and self-retaining driver system of claim 1 , wherein the at least one recess of the head of the bone screw includes at least two slots that receive a corresponding one of the at least one projection of the bone screwdriver.

3. The bone screw and self-retaining driver system of claim 1 , wherein the at least one recess of the head of the bone screw includes a recessed structure having a shape that corresponds to the at least one projection of the bone screwdriver.

4. The bone screw and self-retaining driver system of claim 1 , wherein the bone screwdriver being cannulated includes the internal shaft being cannulated as well as the handle portion being cannulated such that the defined passage follows a same axis through the handle portion and the internal shaft.

5. The bone screw and self-retaining driver system of claim 1 , wherein the defined socket is centered with the at least one recess of the head of the bone screw.

6. The bone screw and self-retaining driver system of claim 5 , wherein the defined socket and the defined passage of the bone screw are aligned to have a same axis as the longitudinal axis of the bone screw.

7. The bone screw and self-retaining driver system of claim 1 , wherein the external shaft defines a longitudinal space within which the internal shaft rotates.

8. The bone screw and self-retaining driver system of claim 1 , wherein the bone screwdriver further comprises: a compression mechanism that pushes the internal shaft towards the distal end of the external shaft.

9. The bone screw and self-retaining driver system of claim 8 , wherein the compression mechanism includes a spring disposed within the handle, the spring pushing the internal shaft towards the distal end of the external shaft.

10. The bone screw and self-retaining driver system of claim 1 , wherein the bone screwdriver further comprises an internal shaft release mechanism that enables removal of the internal shaft from bone screwdriver.

11. The bone screw and self-retaining driver system of claim 10 , wherein the bone screwdriver further comprises: a compression mechanism that pushes the internal shaft towards the distal end of the external shaft.

12. The bone screw and self-retaining driver system of claim 11 , wherein the internal shaft release mechanism includes an end cap that removably engages with a proximal end of the handle portion, wherein the compression mechanism includes a spring located within the end cap.

13. The bone screw and self-retaining driver system of claim 1 , wherein the internal shaft extends through a longitudinal extent of the rotatable wheel along the longitudinal axis of the bone screwdriver, and wherein a portion of the internal shaft proximal to the rotatable wheel is positioned within a portion of the cannulation extending through the handle portion.

Assignees

• Santangelo Stephen Anthony
• Wyman Jeffrey
• Etherington Neil J
• Boileau Pascal
• Smith & Nephew Inc

Inventors

• Santangelo Stephen Anthony
• Wyman Jeffrey
• Etherington Neil J
• Boileau Pascal

Classifications

• A61B17/864

  hollow, e.g. with socket or cannulated · CPC title

• A61B2017/0042

  with special provisions for gripping · CPC title

• A61B17/8883

  the driver bit acting on the periphery of the screw head · CPC title

• A61B17/862

  at the periphery of the screw head · CPC title

• A61B17/8615 Primary

  at the central region of the screw head · CPC title