Posterior cervical fixation system

• US 9,956,009 B1
• Filed: 06/14/2016
• Issued: 05/01/2018
• Est. Priority Date: 03/01/2011
• Status: Active Grant

• Current Assignee: Nuvasive Incorporated
• Original Assignee: Nuvasive Incorporated
• Inventors: Shoshtaev, Eugene
• Primary Examiner(s): Robert, Eduardo C
• Assistant Examiner(s): ECKMAN, MICHELLE CHRISTINE
• Application Number:
  US15/182,414
• Time in Patent Office: 686 Days
• Field of Search: 606250-253
• CPC Class Codes: A61B 17/7013 the shape of the element being adjustable before use adjustable length plates A61B17/7014
• CPC Class Codes: A61B 17/7037 wherein pivoting is blocked when the rod is clamped
• CPC Class Codes: A61B 17/7049 Connectors, not bearing on the vertebrae, for linking longitudinal elements together A61B17/7055, A61B17/7053, A61B17/7019 take precedence
• CPC Class Codes: A61B 17/705 for linking adjacent ends of longitudinal elements
• CPC Class Codes: A61B 17/7052 of variable angle or length
• CPC Class Codes: A61B 17/7055 connected to sacrum, pelvis or skull
• CPC Class Codes: A61B 17/7056 Hooks with specially-designed bone-contacting part
• CPC Class Codes: A61B 17/7064 Devices acting on, attached to, or simulating the effect of, vertebral facets; Tools therefor
• CPC Class Codes: A61B 17/7082 for driving, i.e. rotating, screws or screw parts specially adapted for spinal fixation, e.g. for driving polyaxial or tulip-headed screws driving other bone screws A61B17/8875
• CPC Class Codes: A61B 17/8061 specially adapted for particular bones A61B17/70 and A61B17/74 take precedence

Abstract

A posterior cervical fixation system including an occipital plate member, a cross connector, a pair of elongated spinal rods and a plurality of polyaxial screws. The occipital plate member configured for fixing to an occipital bone comprises an aperture to receive a bone anchor member to secure the occipital plate member to the occipital bone and at least one rod clamping element dimensioned to receive at least one spinal rod. The cross connector secures the pair of elongated spinal rods to vertebral bodies. The cross connector includes a pair of collet connectors and a cross bar that is configured to secure the pair of elongated spinal rods in a desired distance. Each polyaxial screw has an anchor head associated with a fastening member. The pair of elongated spinal rods is configured to extend along the vertebral bodies between the occipital plate member and at least one of the polyaxial screws.

Claims

1. A cross connector for securing a first elongated spinal rod and a second elongated spinal rod to vertebral bodies, comprising:

a cross bar and a pair of ball spring collars situated at each end of said cross bar, the ball spring collars each having an outer spherical surface and an inner surface that slideably engages an exterior surface of the cross bar; and

a pair of collet connectors, each collet connector having a collet head, a clamp and a locking member, each said clamp including a spherical pocket holding one of the ball spring collars, the ball spring collar being rotatable within the spherical pocket to adjust the angular relationship between the cross bar and the clamp, each said collet head including a recess to receive an anchor head of a polyaxial screw, said locking members each being tightened over one of said clamps, compressing the ball spring collars within the spherical pocket and against the exterior surface of the cross bar to inhibit the angular and slidable adjustability of the cross bar relative to the clamps.

2. The cross connector of claim 1, wherein said spherical pocket of each of said clamps is flanked by a conical passage through which the cross bar passes to accommodate the angular adjustability of the cross bar.

3. The cross connector of claim 1, wherein said locking member comprises a lock nut.

4. A cross-connector for providing stability to first and second elongated spinal rods, comprising:

a cross bar having a first end and a second end, said first end having a first ball spring collar coupled thereto and said second end a second ball spring collar coupled thereto, the first and second ball spring collars each having a spherical outer surface and an inner surface that slideably engages an exterior surface of the cross bar;

a first connector configured to directly attach with a first polyaxial screw while accommodating a first spinal rod coupled to the first polyaxial screw, said first connector includes a first collet head having a recess to receive an anchor head of said polyaxial screw and a plurality of cutouts to accommodate said first elongated spinal rod, a first clamp having a first spherical pocket to hold said first ball spring collar of said cross bar;

a second connector configured to directly attach with a second polyaxial screw while accommodating a second spinal rod coupled to the second polyaxial screw, said second connector includes a second collet head having a recess to receive an anchor head of said second polyaxial screw and a plurality of cutouts to accommodate said second elongated spinal rod, a second clamp having a second spherical pocket to hold said second ball spring collar of said cross bar, wherein the first ball spring collar is rotatable within the spherical pocket of the first clamp and the second ball spring collar is rotatable within the spherical pocket of the second clamp such that the angular orientation of the cross is adjustable relative to the first and second clamps; and

first and second locking members, the first locking member coupling with the first connector to engage the first clamp, compressing the first ball spring collar within the spherical pocket and against the exterior surface of the cross bar to inhibit the angular and slidable adjustability of the cross bar relative to the first clamps, the second locking member coupling with the second connector to engage the to engage the second clamp, compressing the second ball spring collar within the spherical pocket and against the exterior surface of the cross bar to inhibit the angular and slidable adjustability of the cross bar relative to the second clamp.

5. The cross connector of claim 4, wherein said spherical pocket of each of said clamps is flanked by a conical passage through which the cross bar passes to accommodate the angular adjustability of the cross bar.

6. The cross connector of claim 4, wherein said first and second locking members each comprise a locknut.