Abstract: An apparatus and method is provided for interbody fusion including distracting, in a given direction, and supporting opposing vertebral bodies. A plurality of wafers are consecutively inserted between the vertebral bodies to create a column of wafers. The column of wafers is oriented between the vertebral bodies so as to expand in the given direction as the wafers are consecutively added to the column.

Abstract: An expandable interbody fusion device includes superior and inferior endplates that are configured to receive a sequentially inserted stack of interlocking expansion members or wafers. The like-configured wafers include features on their top and bottom surfaces that interlock the wafers in multiple degrees of freedom so that the wafer stack is not disrupted when the fusion device is fully expanded. One of the interlocking features includes a plurality of prongs projecting from an upper surface of the wafers and into a recess defined in the lower surface of an adjacent previously inserted like-configured wafer. The prongs and recesses are configured to prevent retrograde movement of each new wafer in a direction opposite the direction of insertion. Other interlocking features prevent movement in the direction of insertion, transverse to the insertion direction and vertically within the stack.

Abstract: An expandable interbody fusion device includes superior and inferior plates that are configured to receive a sequentially inserted stack of expansion members or wafers. The superior and inferior plates include features that at least initially interlock the two plates until the superior plate is dislodged by pressure from the growing wafer stack. The wafers include features on their top and bottom surfaces that interlock the wafers in multiple degrees of freedom so that the wafer stack is not disrupted when the fusion device is fully expanded. Each wafer also includes features that interlock with the inferior plate until the wafer is dislodged by sequential introduction of another wafer.

Abstract: A dynamic stabilization device includes end caps that define a bore for receiving a corresponding bone screw therethrough. A spacer is engaged between each end cap and a cable passes through each of the components and is placed in tension to couple the spacer between the two end caps. The spacer is formed of a material that allows some flexible movement after implantation. An alternative stabilization device includes a spacer over-molded about two bushings defining the bores. According to a method of use, a stabilization device is passed along guide wires through a small incision. Once the device is in contact with the vertebrae, the bone screws are advanced along the guide wires and driven into the bone. One fastener bore may include a camming surface that causes distraction of the vertebrae as the bone screw is threaded into the vertebral bone.

Abstract: A syringe-to-syringe mixing apparatus comprises first and second syringes adapted to be coupled at their respective outlets to fluidly connect the syringes. The first syringe includes a plunger having a hollow plunger barrel and a distal end defining a lumen therethrough. The lumen is initially closed by a septum, which in one embodiment is an elastomeric stopper mounted over the end of the plunger. The mixing apparatus further includes a third syringe slidably disposed within the plunger barrel. The third syringe includes a hollow needle adapted to pierce the septum to allow fluid from the third syringe to be injected into fluid within the coupled first and second syringes.

Abstract: An expandable interbody fusion device includes superior and inferior endplates that are configured to receive a sequentially inserted stack of interlocking expansion members or wafers. The like-configured wafers include features on their top and bottom surfaces that interlock the wafers in multiple degrees of freedom so that the wafer stack is not disrupted when the fusion device is fully expanded. One of the interlocking features includes a plurality of prongs projecting from an upper surface of the wafers and into a recess defined in the lower surface of an adjacent previously inserted like-configured wafer. The prongs and recesses are configured to prevent retrograde movement of each new wafer in a direction opposite the direction of insertion. Other interlocking features prevent movement in the direction of insertion, transverse to the insertion direction and vertically within the stack.

Abstract: A composition suitable for use as replacement material for all or part of a disc nucleus during percutaneous injection, the composition comprising: an injectable, curable, cross-linkable, non-immunogenic non-toxic protein hydrogel that (i) the protein component of the protein hydrogel contains at least one crosslinkable amino acid (ii) has a static compressive modulus of at least about 10 kPa, and (iii) has a dynamic compressive modulus of at least about 10 kPa; an iodinated contrast solution comprising an amount of an iodine compound sufficient to increase radiopacity to a discernable level, wherein the solution causes a decrease in the static and/or dynamic compressive modulus; and an amount of a crosslinker sufficient to restore at least about 100% of the decrease in static and/or dynamic compressive modulus caused by addition of the iodinated contrast solution.

Abstract: An expandable interbody fusion device includes superior and inferior plates that are configured to receive a sequentially inserted stack of expansion members or wafers. The superior and inferior plates include features that at least initially interlock the two plates until the superior plate is dislodged by pressure from the growing wafer stack. The wafers include features on their top and bottom surfaces that interlock the wafers in multiple degrees of freedom so that the wafer stack is not disrupted when the fusion device is fully expanded. Each wafer also includes features that interlock with the inferior plate until the wafer is dislodged by sequential introduction of another wafer.

Abstract: A system and method is provided for maintaining a proper intervertebral disc height during the replacement or augmentation of the spinal disc. In one embodiment, a cannulated distractor is used to distract the adjacent vertebrae and maintain a proper disc space height. The cannulated distractor is fluidly connected to a source of fluent material for injection into the disc space. The distraction includes a distraction tip resident within the disc space that includes a central lumen and a number of openings communicating with the lumen to dispense the fluent material within the disc space.

Abstract: An apparatus and method is provided for distracting, in a given direction, and supporting opposed endplates of a vertebral body. A plurality of wafers are consecutively inserted within the vertebral body between the two endplates to create a column of wafers. The column of wafers is oriented between the endplates so as to expand in the given direction as the wafers are consecutively added to the column.

Abstract: An expandable interbody fusion device for implantation into the intradiscal space between two opposing vertebral bodies of a spine comprises a superior endplate member having an upper surface for engaging a superior vertebral body in a spine, and an inferior endplate member having a lower surface for engaging an inferior vertebral body in the spine. The superior endplate member and the inferior endplate member are releasably coupled and define a cavity therebetween. At least one expansion member is configured to be introduced into the cavity to move the superior endplate and the inferior endplate members relatively apart upon introduction and to thereby decouple the superior endplate member and the inferior endplate member. An inserter may be releasably coupled to the device to facilitate insertion of the device as well as to provide a track for insertion of the expansion members.

Abstract: An apparatus and method for distracting, in a given direction, and supporting two tissue surfaces. An expandable implant includes a plurality of elements are consecutively inserted between the two tissue surfaces to create a column of elements. The column of elements is oriented between the tissue surfaces so as to expand in the given direction as the elements are consecutively added to the column. The expandable implant includes a constraint including a cooperative engagement structure between adjacent elements.

Abstract: An apparatus and method for distracting, in a given direction, and supporting two tissue surfaces. A plurality of wafers are consecutively inserted between the two tissue surfaces to create a column of wafers. The column of wafers is oriented between the tissue surfaces so as to expand in the given direction as the wafers are consecutively added to the column.

Abstract: A system and method is provided for distracting opposite surfaces from the interior of a bone, such as a vertebral body. A working channel cannula provides a working channel through which an inserter and an injection cannula can simultaneously pass. The inserter transports a plurality of wafers into the interior of the bone to form a load-bearing stack bearing against the opposite surfaces. The injection cannula is used to inject a fluent material into and/or around the stack. In certain embodiments, the fluent material is a load-bearing or hardenable material, such as bone cement. In other embodiments, the fluent material can be a BMP, HAP, or other osteo-inductive, osteo-conductive, or pharmaceutical compositions. A syringe containing the fluent material is engaged to the injection cannula and is operable to inject the fluent material into the vertebral body under controlled pressure.

Abstract: A method for treating a diseased or damaged spinal disc comprises the steps of: (a) providing access to the nucleus pulposus through the annulus; (b) removing at least a portion of the nucleus pulposus to create an intradiscal space; (c) determining the size of the intradiscal space; and (d) sealably introducing under pressure a curable biomaterial through the annulus directly into the intradiscal space. The step of determining the size of the intradiscal space may be accomplished by expanding a compliant balloon within the intradiscal space using a contrast medium capable of visualization under fluoroscopy. The curable material is sealably introduced through a vented needle inserted through the opening. The curable biomaterial is introduced until a quantity of the material flows into the vent.

Abstract: A method and assembly is provided for linking an additional vertebral construct to an existing spinal construct having at least two bone screws engaged to corresponding vertebrae and connected by a connecting member. The assembly includes a fastener configured to engage a bone screw of the existing construct and to engage a connecting member connected to the bone screw. The assembly further includes a linking member having an elongated portion configured to connect to a bone screw of the additional construct and a mounting structure configured for mounting on the bone screw of the existing construct. A locking member fixes the orientation of the linking member relative to the bone screw and a clamping member locks the linking member and existing connecting member to the bone screw of the existing construct.

Abstract: A cross connector for attachment between two spinal implants comprises a first element having one end and an opposite end configured for engaging one of the two spinal implants, a second element having one end and an opposite end configured for engaging the other of the two spinal implants, an engagement mechanism between the one end of each of the first and second elements, and a locking element for locking the two elements together at the respective one end. The engagement mechanism includes an interface configured to permit relative pivoting between the first element and the second element about at least two non-parallel axes.

Abstract: A method for treating a spinal disc comprises the steps of: determining the integrity of the annulus by subjecting the annulus to a first pressure applied internally of the annulus; providing access to the nucleus pulposus through the annulus without removing any tissue from the annulus or from the nucleus pulposus; and sealably injecting curable biomaterial through the annulus access directly into the nucleus pulposus at a second pressure correlated with the first pressure. The integrity of the annulus may be determined by a pre-operative discogram using a contrast medium that has a viscosity substantially similar to the viscosity of the biomaterial to be injected. The curable biomaterial may be injected under a pressure sufficient to distract opposing vertebral bodies communicating with the disc space.

Abstract: A composite tissue formed in situ is provided. The composite tissue includes a synovial joint tissue; and a barrier material adhered thereto for sealing the synovial joint tissue against synovial fluid. Also provided is a method for regenerating synovial joint tissue in situ by excluding synovial fluid therefrom. The method includes providing a synovial joint tissue having a defect; and placing a barrier material in intimate contact with the defect for sealing the defect against synovial fluid. The barrier material includes a curable protein copolymer. The method further includes curing the protein copolymer in situ. The barrier material can include a crosslinked network, or a self gelled network of repeating elastin-like and fibroin-like polymer chains.

Abstract: A surgical instrument and method is provided for creating and preparing a cavity in a bony intervertebral body. Asymmetrical cutting structures selectively open a cavity which has a relatively large surface area in the vertical direction. One method pertains to the treatment of a vertebral compression fracture.