Percutaneous access devices and bone anchor assemblies

• US 7,854,751 B2
• Filed: 03/28/2007
• Issued: 12/21/2010
• Est. Priority Date: 12/16/2003
• Status: Active Grant

• Current Assignee: Depuy Spine Sarl (Johnson & Johnson)
• Original Assignee: Dupuy Spine, Inc.
• Inventors: Lopez, Erasmo, Ruberte, Ramon, Sicvol, Christopher
• Primary Examiner(s): Barrett; Thomas C
• Assistant Examiner(s): WOODALL, NICHOLAS W
• Application Number:
  US11/692,531
• Publication Number:
  US 20070167954A1
• Time in Patent Office: 1,364 Days
• Field of Search: 606/96, 606/99, 606/104, 606/323, 606/86.A, 606/916, 606/246, 606/251, 606/252, 606273-274, 606/276
• US Class Current: 606/246
• CPC Class Codes: A61B 17/70 Spinal positioners or stabilisers ; Bone stabilisers comprising fluid filler in an implant
• CPC Class Codes: A61B 17/7032 Screws or hooks with U-shaped head or back through which longitudinal rods pass
• CPC Class Codes: A61B 17/7034 characterised by a lateral opening
• CPC Class Codes: A61B 17/7035 Screws or hooks, wherein a rod-clamping part and a bone-anchoring part can pivot relative to each other
• CPC Class Codes: A61B 17/7037 wherein pivoting is blocked when the rod is clamped
• CPC Class Codes: A61B 17/7076 for driving, positioning or assembling spinal clamps or bone anchors specially adapted for spinal fixation
• CPC Class Codes: A61B 17/708 with tubular extensions coaxially mounted on the bone anchors
• CPC Class Codes: A61B 17/7091 for applying, tightening or removing longitudinal element-to-bone anchor locking elements, e.g. caps, set screws, nuts or wedges
• CPC Class Codes: A61B 17/8605 Heads, i.e. proximal ends projecting from bone
• CPC Class Codes: A61B 2017/564 Methods for bone or joint treatment
• CPC Class Codes: A61B 2090/037 with a frangible part, e.g. by reduced diameter

Abstract

A percutaneous access device includes an inner tube and an outer tube disposed about at least a portion of the inner tube. The outer tube may be sized to span from a skin incision in a patient to a site proximate the spine of the patient. The distal end of the outer tube may be adapted to releasably engage a bone anchor. The inner tube may be adjustable relative to the outer tube between a first position and a second position in which the distal end of the inner tube contacts the bone anchor. A bone anchor assembly includes a bone anchor having a distal bone engaging portion and a receiving member having a recess for receiving a spinal fixation element. The proximal end of the receiving member may have an arcuate groove formed on an exterior surface thereof to facilitate connection of an instrument to the receiving member.

Claims

1. In the combination of a bone attachment structure having a receiver and a guide tool having receiver attachment structure at a lower end thereof that is operably mateable with the receiver, the improvement comprising:

a) the receiver having an aperture and a recess communicating with the aperture; and

b) the guide tool including a inner tube having a proximal end, a distal end and a lumen extending from the proximal end to the distal end, the inner tube having a first slot formed therein, the first slot opening at the distal end and extending a first slot length toward the proximal end of the inner tube, the guide tool including an outer tube coaxially disposed about the inner tube, the outer tube having a proximal end, a distal end and a lumen extending from the proximal end to the distal end, the outer tube having a second slot formed therein, the second slot opening at the distal end and extending a second slot length toward the proximal end of the outer tube, the distal end of the outer tube having an inner projection, the projection having mating structure receivable in the recess for operably resisting radial splaying and separation of the tool from the receiver when joined together.

2. In the combination of a bone screw having a head and a manipulation tool having attachment structure at a lower end thereof that is operably mateable with the bone screw head;

the improvement comprising;

a) the bone screw head having a top, a bottom, and a circumferentially extending undercut first surface facing downwardly toward said bottom;

b) the manipulation tool including a inner tube having a proximal end, a distal end and a lumen extending from the proximal end to the distal end, the inner tube having a first slot formed therein, the first slot opening at the distal end and extending a first slot length toward the proximal end of the inner tube, the manipulation tool including an outer tube coaxially disposed about the inner tube, the outer tube having a proximal end, a distal end and a lumen extending from the proximal end to the distal end, the outer tube having a second slot formed therein, the second slot opening at the distal end and extending a second slot length toward the proximal end of the outer tube, the distal end of the outer tube having a projection with a circumferentially extending second surface; and

c) the first and second surfaces being sized, shaped and positioned to provide for operable mating overlapping alignment of the manipulation tool relative to the bone screw head.

3. The improvement of claim 2 wherein:

a) the undercut first surface includes a recess and the projection includes extending second surface mating structure that overlaps with the undercut surface in the recess so as to operably resist splaying and separation of the manipulation tool from the receiver when joined together.

4. A spinal system comprising:

a bone anchor assembly having a bone screw and a receiver member coupled to the bone screw for receiving a spinal fixation element, the receiver member having a proximal end, a distal end, a bore extending from the proximal end to the distal end, and a recess intersecting the bore for receiving the spinal fixation element, the bore defining a bore axis, the proximal end of the receiver member having a generally U-shaped cross-section defined by two spaced apart legs separated by the recess, each leg having a free proximal end including an arcuate groove on an exterior surface thereof, each arcuate groove having a proximal surface, a distal surface, and an interconnecting surface, the proximal surface being angled distally at a non-zero angle relative to a plane orthogonal to the bore axis;

an instrument having a tubular body, the tubular body having a proximal end, a distal end and a lumen extending from the proximal end to the distal end, the instrument including an inner tube, the tubular body disposed about at least a portion of the inner tube, the tubular body having a pair of opposed tabs separated by a pair of opposed slots, the slots opening at the distal end and extending a slot length toward the proximal end of the tubular body, each tab including an inward projection at a distal end of the tab, each projection being sized and shaped to fit within one of the arcuate grooves of the receiver member and thereby releasable connect the instrument to the bone anchor assembly.

5. The system of claim 4, wherein the proximal surface of each arcuate groove is angled distally at a non-zero angle relative to a plane orthogonal to the bore axis.

6. The system of claim 4, wherein each inward projection of the tabs includes a proximal surface oriented at an angle approximately equal to the angle of the proximal surface of the corresponding arcuate groove.

7. The system of claim 4, wherein the inner tube includes a pair of opposed tabs separated by a pair of opposed slots, the slots opening at a distal end of the inner tube and extending a slot length toward a proximal end of the inner tube.

8. The system of claim 4, wherein the inner tube is adjustable relative to the tubular body along a longitudinal axis of the tubular body.