Orthopedic implant

• US 9,072,554 B2
• Filed: 11/19/2008
• Issued: 07/07/2015
• Est. Priority Date: 09/21/2005
• Status: Expired due to Fees

• Current Assignee: Children's Hospital & Medical Center, SpineForm, LLC
• Original Assignee: Children's Hospital & Medical Center, SpineForm, LLC
• Inventors: Reynolds, Joseph E., Crawford, Alvin H., Wall, Eric J.
• Primary Examiner(s): Schaper, Michael T
• Application Number:
  US12/274,039
• Publication Number:
  US 20090287249A1
• Time in Patent Office: 2,421 Days
• Field of Search: 606280-299, 606309-318, 411308-311, 411/415, 411/426
• US Class Current: 1/1
• CPC Class Codes: A61B 17/0642 for bones, e.g. for osteosynthesis or connecting tendon to bone
• CPC Class Codes: A61B 17/7059 Cortical plates A61B17/7007, A61B17/7058 take precedence
• CPC Class Codes: A61B 17/8033 having indirect contact with screw heads, or having contact with screw heads maintained with the aid of additional components, e.g. nuts, wedges or head covers
• CPC Class Codes: A61B 17/8047 wherein the additional element surrounds the screw head in the plate hole A61B17/8052 takes precedence
• CPC Class Codes: A61B 17/8052 immobilised relative to screws by interlocking form of the heads and plate holes, e.g. conical or threaded
• CPC Class Codes: A61B 17/8057 the interlocking form comprising a thread
• CPC Class Codes: A61B 17/809 with bone-penetrating elements, e.g. blades or prongs bone staples A61B17/0642; intramedullary nails with a plate at an end A61B17/7233

Abstract

An orthopedic implant, illustratively a spinal staple, including pre-attached fasteners.

Claims

1. A pre-assembled implant device comprising:

an orthopedic implant including an upper surface and a lower surface; and

a bone screw pre-attached to the implant in a secured mode of operation resisting axial movement of the bone screw relative to the implant prior to placement within a bone, wherein increased torque will cause the bone screw to enter a released mode of operation following the secured mode of operation permitting rotational movement and resulting axial movement of the bone screw in a direction toward the bone, the bone screw extending between proximal and distal ends, including a head supported at the proximal end, and including a bone engaging tip supported at the distal end, wherein the bone engaging tip of the bone screw extends below the lower surface of the orthopedic implant in the secured mode of operation;

wherein the implant includes a spinal staple having a receiving opening with an internal thread, and the bone screw includes an external thread configured to interfere with the internal thread and thereby pre-attach the bone screw to the spinal staple;

wherein at least one revolution of the external thread has a major diameter greater than a minor diameter of the internal thread; and

wherein the head of the bone screw includes a radially outwardly extending protrusion, and the receiving opening of the spinal staple includes a recess, the protrusion and the recess configured to interlock and prevent back-out of the bone screw following bone engagement.

2. An orthopedic implant device comprising:

a body having a first surface, a second surface opposed to the first surface and configured to face a bone, and a fastener receiving opening extending between the first and second surfaces;

a bone screw received within the fastener receiving opening of the body and configured to be inserted into the bone, the bone screw extending between proximal and distal ends and including a threaded portion, a head supported at the proximal end, and a bone engaging tip supported at the distal end;

a releasable securing member configured to pre-attach the bone screw to the body prior to placement of the bone screw within the bone in a secured mode of operation resisting axial movement of the bone screw relative to the fastener receiving opening of the body, wherein an applied torque will cause the bone screw to enter a released mode of operation following the secured mode of operation permitting rotational movement and resulting axial movement of the bone screw within the fastener receiving opening of the body in a direction from the first surface toward the second surface, and the bone engaging tip of the bone screw extends beyond the second surface of the body in the secured mode of operation;

wherein the receiving opening of the body includes an internal thread and the threaded portion of the bone screw includes an external thread, the releasable securing member being configured to resist rotational movement and resulting axial movement of the bone screw in the secured mode of operation, and to permit rotational movement and resulting axial movement of the bone screw within the receiving opening in the released mode of operation;

wherein the releasable securing member comprises a single interfering revolution of the external thread providing an interference fit with the internal thread;

wherein the interfering revolution of the external thread has a major diameter greater than a major diameter of the internal thread;

wherein the external thread includes a non-interfering revolution configured to permit rotation relative to the internal thread in the released mode of operation; and

wherein the non-interfering revolution of the external thread has a major diameter less than the major diameter of the interfering revolution of the external thread and sized to rotate relative to the internal thread in the released mode of operation.

3. The orthopedic implant device of claim 2, wherein a torque of at least about 0.2 Newton-meters is required to release the securing member.

4. The orthopedic implant device of claim 2, wherein the releasable securing member comprises a deformable member supported by the body and extending within the receiving opening.

5. The orthopedic implant device of claim 2, wherein the head of the bone screw includes a protrusion, and the receiving opening of the body includes a recess, the protrusion and the recess configured to interlock and prevent back-out of the bone screw following bone engagement.

6. The orthopedic implant device of claim 2, wherein the body comprises a spinal staple having a bridge member, a pair of legs coupled to opposing ends of the bridge member, and a pair of fastener retaining portions defining a pair of the fastener receiving openings.

7. An orthopedic implant device comprising:

a spinal staple including a bridge member having an upper surface, an opposed lower surface, a first end, an opposed second end, a first leg proximate the first end and configured to be inserted into a first vertebra, a second leg proximate the second end and configured to be inserted into a second vertebra, a fastener retaining portion extending from the bridge member first end and including an upper surface, a lower surface and a fastener receiving opening extending between the upper surface of the fastener retaining portion and the lower surface of the fastener retaining portion, the lower surface of the fastener retaining portion configured to face the first vertebra;

a fastener configured to couple the spinal staple to the first vertebra, and including a bone engaging tip configured to penetrate the first vertebra;

a releasable securing member configured to pre-attach the fastener to the spinal staple in a secured mode of operation resisting axial movement of the fastener relative to the spinal staple prior to coupling of the spinal staple to the first vertebra and the second vertebra, wherein an applied torque will cause the fastener to enter a released mode of operation following the secured mode of operation permitting rotational movement and resulting axial movement of the fastener in a direction toward the first vertebra, the fastener extending from the lower surface of the fastener retaining portion in the secured mode of operation;

wherein the fastener comprises a bone screw received within the fastener receiving opening of the spinal staple and configured to be inserted into the first vertebra, the bone screw including an elongated shank extending between proximal and distal ends and including a threaded portion, the releasable securing member configured to resist axial movement of the bone screw relative to the fastener receiving opening of the spinal staple in the secured mode of operation;

wherein the fastener receiving opening of the spinal staple includes at least one internal thread and the threaded portion of the bone screw includes at least one external thread, and the releasable securing member comprises an interfering revolution of the external thread providing an interference fit with the internal thread;

wherein the interfering revolution of the external thread has a major diameter greater than a major diameter of the internal thread;

wherein the external thread includes a non-interfering revolution configured to permit rotation relative to the internal thread in the released mode of operation; and

wherein the non-interfering revolution of the external thread has a major diameter less than the major diameter of the interfering revolution of the external thread and sized to rotate relative to the internal thread in the released mode of operation.

8. The orthopedic implant device of claim 7, wherein a torque of at least about 0.2 Newton-meters is required to release the securing member.

9. The orthopedic implant device of claim 7, wherein the releasable securing member comprises a deformable member supported by the spinal staple and extending within the receiving opening.

10. The orthopedic implant device of claim 7, wherein the bone screw includes a head having at least one protrusion, and the receiving opening of the spinal staple includes at least one recess, the protrusion and the recess configured to interlock and prevent back-out of the bone screw following bone engagement.