Expandable vertebral device with cam lock

• US 8,353,961 B2
• Filed: 02/06/2009
• Issued: 01/15/2013
• Est. Priority Date: 02/07/2008
• Status: Expired due to Fees

• Current Assignee: K2M, Inc (Stryker Corporation)
• Original Assignee: K2M, Inc (Stryker Corporation)
• Inventors: McClintock, Larry, Strauss, Kevin R., Durrani, Atiq
• Primary Examiner(s): Stewart, Alvin
• Assistant Examiner(s): JOHANAS, JACQUELINE T
• Application Number:
  US12/366,805
• Publication Number:
  US 20090204215A1
• Time in Patent Office: 1,439 Days
• Field of Search: 623 1711- 1716
• US Class Current: 623/17.15
• CPC Class Codes: A61F 2/44 for the spine, e.g. vertebrae, spinal discs
• CPC Class Codes: A61F 2/442 Intervertebral or spinal discs, e.g. resilient non-disc-shaped intervertebral inflatable pockets A61F2/441; non-disc-shaped intervertebral fusion implants A61F2/4455
• CPC Class Codes: A61F 2/4455 for the fusion of spinal bodies, e.g. intervertebral fusion of adjacent spinal bodies, e.g. fusion cages intervertebral discs A61F2/442
• CPC Class Codes: A61F 2/4611 of spinal prostheses
• CPC Class Codes: A61F 2002/30331 made by longitudinally pushing a protrusion into a complementarily-shaped recess, e.g. held by friction fit
• CPC Class Codes: A61F 2002/30476 locked by an additional locking mechanism
• CPC Class Codes: A61F 2002/30495 using a locking ring
• CPC Class Codes: A61F 2002/30505 spring biased
• CPC Class Codes: A61F 2002/3052 unrestrained in only one direction, e.g. moving unidirectionally
• CPC Class Codes: A61F 2002/3055 for adjusting length
• CPC Class Codes: A61F 2002/30601 telescopic
• CPC Class Codes: A61F 2002/30772 Apertures or holes, e.g. of circular cross section
• CPC Class Codes: A61F 2002/30904 serrated profile, i.e. saw-toothed
• CPC Class Codes: A61F 2002/4627 with linear motion along or rotating motion about the instrument axis or the implantation direction, e.g. telescopic, along a guiding rod, screwing inside the instrument
• CPC Class Codes: A61F 2002/4629 connected to the endoprosthesis or implant via a threaded connection
• CPC Class Codes: A61F 2220/0025 Connections or couplings between prosthetic parts, e.g. between modular parts; Connecting elements
• CPC Class Codes: A61F 2220/0033 made by longitudinally pushing a protrusion into a complementary-shaped recess, e.g. held by friction fit

Abstract

An expandable cage supports adjacent vertebra in spine surgery. The expandable cage includes a first supporting member configured to engage tissue and a second supporting member operatively associated with the first supporting member. The first and second supporting members are movable relative to each other. The expandable cage further includes a cam lock mechanism configured to maintain the first and second supporting members in a fixed relative position. In another embodiment, the expandable cage includes a ring plate lock mechanism in lieu of the cam lock mechanism. The ring plate lock mechanism is adapted to maintain the first and second supporting members in a fixed relative position.

Claims

1. An apparatus for spinal surgery, comprising:

a first supporting member configured to engage tissue;

a second supporting member configured to engage tissue and operatively associated with the first supporting member, wherein the first and second supporting members are movable relative to each other; and

a lock mechanism, the lock mechanism including;

a camming member rotatable about a pivot pin between a locked condition, wherein the camming member engages at least one of the first and second supporting members to maintain the first and second supporting members in a fixed relative position, and an unlocked condition, wherein the camming member is rotated out of engagement with the at least one of the first and second supporting members to permit movement of the first and second supporting members relative to one another;

a biasing member configured to bias the camming member towards the locked condition; and

a fastener operably positioned relative to the camming member, the fastener movable between a first position, wherein the fastener is spaced-apart from the camming member allowing the biasing member to bias the camming member towards the locked condition, and a second position, wherein the fastener is in contact with and urges the camming member against the bias of the biasing member towards the unlocked condition, the fastener threadingly engaged within a threaded opening such that rotation of the fastener in a first direction moves the fastener towards the first position and such that rotation of the fastener in a second, opposite direction moves the fastener towards the second position.

2. The apparatus of claim 1, wherein the first supporting member includes a longitudinal opening and the second supporting member includes a column adapted to be slidably received in the longitudinal opening.

3. The apparatus of claim 2, wherein the camming member frictionally engages the column when located in the locked condition to maintain the first and second supporting members in fixed position relative to one another.

4. The apparatus of claim 1, wherein the first supporting member includes an elongate body extending toward the second supporting member, the elongate body having a threaded hole adapted to receive a portion of an insertion tool.

5. The apparatus of claim 4, wherein the elongate body includes an opening leading to the lock mechanism, the opening being adapted to receive a portion of the insertion tool.

6. The apparatus of claim 4, wherein the elongate body includes an arc-shaped recess extending therealong, the arc-shaped recess being adapted to receive a portion of the insertion tool.

7. The apparatus of claim 1, wherein the first and second supporting members are movable relative to each other along an expansion axis, and wherein the camming member is rotatable about a pivot axis of the pivot pin, the pivot axis disposed in transverse relation relative to the expansion axis.

8. The apparatus of claim 1, wherein the fastener defines a socket for receiving a driving tool for moving the fastener between the first and second positions.

9. The apparatus of claim 1, wherein the camming member includes a first end, a second end, and a middle portion, the pivot pin extending through the middle portion of the camming member.

10. The apparatus of claim 9, wherein the biasing member is configured to contact the camming member towards the first end thereof to bias the camming member towards the locked condition, and wherein the fastener is configured to contact the camming member towards the second end thereof to urge the camming member against the bias of the biasing member towards the unlocked condition.

11. An apparatus for spinal surgery, comprising:

a first supporting member configured to engage tissue;

a second supporting member configured to engage tissue;

a telescoping connecting member operatively associated with the first and second supporting members, such that the first and second supporting members are movable relative to each other; and

a lock mechanism associated with the telescoping connecting member, the lock mechanism including;

a camming member rotatable about a pivot pin between a locked condition, wherein the camming member engages the telescoping connecting member to maintain the first and second supporting members in a fixed relative position, and an unlocked condition, wherein the camming member is rotated out of engagement with the telescoping connecting member to permit movement of the first and second supporting members relative to one another;

a biasing member configured to bias the camming member towards the locked condition; and

a fastener operably positioned relative to the camming member, the fastener movable between a first position, wherein the fastener is spaced-apart from the camming member allowing the biasing member to bias the camming member towards the locked condition, and a second position, wherein the fastener is in contact with and urges the camming member against the bias of the biasing member towards the unlocked condition, the fastener threadingly engaged within a threaded opening such that rotation of the fastener in a first direction moves the fastener towards the first position and such that rotation of the fastener in a second, opposite direction moves the fastener towards the second position.

12. The apparatus of claim 11, wherein the second supporting member includes a column extending toward the first supporting member.

13. The apparatus of claim 11, wherein the first and second supporting members are movable relative to each other along an expansion axis, and wherein the camming member is rotatable about a pivot axis of the pivot pin, the pivot axis disposed in transverse relation relative to the expansion axis.

14. The apparatus of claim 11, wherein the fastener defines a socket for receiving a driving tool for moving the fastener between the first and second positions.

15. The apparatus of claim 11, wherein the camming member includes a first end, a second end, and a middle portion, the pivot pin extending through the middle portion of the camming member.

16. The apparatus of claim 15, wherein the biasing member is configured to contact the camming member towards the first end thereof to bias the camming member towards the locked condition, and wherein the fastener is configured to contact the camming member towards the second end thereof to urge the camming member against the bias of the biasing member towards the unlocked condition.