Patents by Inventor Robert L. Assell

Robert L. Assell has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 7500977
    Abstract: Disclosed are surgical tools, tool sets and methods for percutaneously accessing and preparing treatment sites within the spine for subsequent treatment procedures. The treatment site may be an inter-vertebral motion segments in the lumbar and sacral regions of the spine. The tool set may comprise introducer tools and bone dilators for accessing and tapping into a targeted site, such as, for example, the anterior surface of the S1 vertebral body. The tool set may also comprise cutters and extractors for preparing the treatment site for subsequent treatment procedures. The tool set may additionally comprise a bone graft inserter, an exchange system, and/or a temporary distraction tool for further preparing the treatment site for subsequent treatment procedures.
    Type: Grant
    Filed: October 22, 2004
    Date of Patent: March 10, 2009
    Assignee: TranS1 Inc.
    Inventors: Robert L. Assell, Steven D. Ainsworth, Andrew L. Cragg, Eugene A. Dickhudt
  • Patent number: 7491236
    Abstract: A spinal mobility preservation apparatus and methods are disclosed. The spinal mobility preservation apparatus may include a proximal body, an intermediate body, a distal body, and an expandable membrane. The proximal body and the distal body secure the mobility preservation apparatus to adjacent vertebral bodies. At least one of an intermediate body and an expandable membrane secure the proximal body to the distal body and provide a degree of support to a spinal motion segment defined by the adjacent vertebral bodies. A single proximal body and an expandable membrane may also compose a spinal mobility preservation apparatus. The proximal body secured to one of a superior or an inferior vertebral body and the expandable membrane extending into the intervertebral disc space to support the spinal motion segment.
    Type: Grant
    Filed: October 22, 2004
    Date of Patent: February 17, 2009
    Assignee: Trans1, Inc.
    Inventors: Andrew H. Cragg, Robert L. Assell, Steven D. Ainsworth, Eugene A. Dickhudt, Bradley J. Wessman
  • Patent number: 7473256
    Abstract: Disclosed are surgical tools, tool sets and methods for percutaneously accessing and preparing treatment sites within the spine for subsequent treatment procedures. The treatment site may be an inter-vertebral motion segments in the lumbar and sacral regions of the spine. The tool set may comprise introducer tools and bone dilators for accessing and tapping into a targeted site, such as, for example, the anterior surface of the S1 vertebral body. The tool set may also comprise cutters and extractors for preparing the treatment site for subsequent treatment procedures. The tool set may additionally comprise a bone graft inserter, an exchange system, and/or a temporary distraction tool for further preparing the treatment site for subsequent treatment procedures.
    Type: Grant
    Filed: October 22, 2004
    Date of Patent: January 6, 2009
    Assignee: TranS1 Inc.
    Inventors: Robert L. Assell, Steven D. Ainsworth, Andrew L. Cragg, Eugene A. Dickhudt
  • Publication number: 20080262555
    Abstract: Instrumentation systems that facilitate the reproducible deployment and placement of fixation device such as a screw, via an aligned, percutaneous access and approach, designed to relieve lower back pain and possibly improve disc health and prevent progression or transition of disease. Information about methods and equipment for accessing and preparing bone for subsequent delivery of a bone screw such as a facet screw across a facet joint. Some of the many teachings contained herein address a system of visual indicators may be used in connection with a bore cutter that operates around an anchored guide wire to avoid dislodging the anchored guide wire.
    Type: Application
    Filed: January 7, 2008
    Publication date: October 23, 2008
    Applicant: TranS1 Inc.
    Inventors: Robert L. Assell, Thomas M. Womble
  • Publication number: 20080262502
    Abstract: Multi-membrane prosthetic nucleus and implants using same are disclosed having an outermost membrane that is semi-compliant and limits the innermost membrane and any intermediate membranes that are highly compliant from bulging out of any opening in the annulus fibrosus. The outermost membrane may help protect the innermost membrane from trauma including any trauma before the innermost membrane is expanded through the injection of prosthetic nucleus material and trauma during the expansion of the innermost membrane in response to the injection of prosthetic nucleus material. Also disclosed is a coated membrane which combines the mechanical properties of the foundation layer with the low permeability to the passage of the flowable prosthetic material of the coating. This coated membrane is semi-compliant and prevents the prosthetic nucleus from bulging out of any openings in the annulus fibrosus. Use is made of injected prosthetic nucleus material that changes to a non-flowable state.
    Type: Application
    Filed: April 2, 2008
    Publication date: October 23, 2008
    Applicant: TRANS1, INC.
    Inventors: Stephen D. Ainsworth, Brandon B. Arthurs, Robert L. Assell, Bradley J. Wessman
  • Publication number: 20080195156
    Abstract: Spinal motion preservation assemblies adapted for use in a spinal motion segment are disclosed including the process for delivering and assembling the spinal motion preservation assemblies in the spinal motion segment via an axial channel created with a trans-sacral approach. The spinal motion preservation assemblies make use of a dual pivot. A number of different embodiments of spinal motion preservation assemblies are disclosed which include at least one component adapted for elastic deformation under compressive loads. The disclosed mobility preservation assemblies provide for dynamic stabilization (DS) of the spinal motion segment.
    Type: Application
    Filed: March 7, 2008
    Publication date: August 14, 2008
    Applicant: TRANS1 INC.
    Inventors: Stephen D. Ainsworth, Robert L. Assell, Eugene A. Dickhudt, Bradley J. Wessman
  • Publication number: 20080188895
    Abstract: A spinal mobility preservation apparatus and methods are disclosed. The spinal mobility preservation apparatus may include a proximal body, an intermediate body, a distal body, and an expandable membrane. The proximal body and the distal body secure the mobility preservation apparatus to adjacent vertebral bodies. At least one of an intermediate body and an expandable membrane secure the proximal body to the distal body and provide a degree of support to a spinal motion segment defined by the adjacent vertebral bodies. A single proximal body and an expandable membrane may also compose a spinal mobility preservation apparatus. The proximal body secured to one of a superior or an inferior vertebral body and the expandable membrane extending into the intervertebral disc space to support the spinal motion segment.
    Type: Application
    Filed: October 31, 2007
    Publication date: August 7, 2008
    Inventors: Andrew H. Cragg, Robert L. Assell, Steven D. Ainsworth, Eugene A. Dickhudt, Bradley J. Wessman
  • Publication number: 20080154275
    Abstract: Disclosed are surgical tools, tool sets and methods for percutaneously accessing and preparing treatment sites within the spine for subsequent treatment procedures. The treatment site may be an inter-vertebral motion segments in the lumbar and sacral regions of the spine. The tool set may comprise introducer tools and bone dilators for accessing and tapping into a targeted site, such as, for example, the anterior surface of the S1 vertebral body. The tool set may also comprise cutters and extractors for preparing the treatment site for subsequent treatment procedures. The tool set may additionally comprise a bone graft inserter, an exchange system, and/or a temporary distraction tool for further preparing the treatment site for subsequent treatment procedures.
    Type: Application
    Filed: March 11, 2008
    Publication date: June 26, 2008
    Applicant: TRANS1 INC.
    Inventors: Robert L. Assell, Stephen D. Ainsworth, Andrew H. Cragg, Eugene A. Dickhudt
  • Patent number: 6921403
    Abstract: The invention provides an implantable spinal distraction/fusion rod with varied thread pitch and diameters along different portions of its length that it is capable of distracting two or more vertebral bodies relative to each other and/or facilitating the procedure of fusing the vertebral bodies together from within the spine. The present invention also provides for methods of using the rod to distract and/or fuse two or more vertebral bodies from within the spine.
    Type: Grant
    Filed: December 3, 2002
    Date of Patent: July 26, 2005
    Assignee: TranS1 Inc.
    Inventors: Andrew H. Cragg, Robert L. Assell, Eugene A. Dickhudt
  • Publication number: 20030158557
    Abstract: The invention provides an implantable spinal distraction/fusion rod with varied thread pitch and diameters along different portions of its length that it is capable of distracting two or more vertebral bodies relative to each other and/or facilitating the procedure of fusing the vertebral bodies together from within the spine. The present invention also provides for methods of using the rod to distract and/or fuse two or more vertebral bodies from within the spine.
    Type: Application
    Filed: December 3, 2002
    Publication date: August 21, 2003
    Inventors: Andrew H. Cragg, Robert L. Assell, Eugene A. Dickhudt
  • Patent number: 6602291
    Abstract: A prosthetic spinal disc nucleus comprising a hydrogel core surrounded by a constraining jacket. The hydrogel core is configured to expand from a dehydrated state to a hydrated state. In the dehydrated state, the hydrogel core has a shape selected to facilitate implantation through an anulus opening. Further, in the hydrated state, the hydrogel core has a shape corresponding generally to a portion of a nucleus cavity, the hydrated shape being different from the dehydrated shape. Upon hydration, the hydrogel core transitions from the dehydrated shape to the hydrated shape.
    Type: Grant
    Filed: April 5, 1999
    Date of Patent: August 5, 2003
    Assignee: Raymedica, Inc.
    Inventors: Charles D. Ray, Robert L. Assell
  • Publication number: 20020183848
    Abstract: A prosthetic spinal disc nucleus comprising a hydrogel core surrounded by a constraining jacket. The hydrogel core is configured to expand from a dehydrated state to a hydrated state. In the dehydrated state, the hydrogel core has a shape selected to facilitate implantation through an anulus opening. Further, in the hydrated state, the hydrogel core has a shape corresponding generally to a portion of a nucleus cavity, the hydrated shape being different from the dehydrated shape. Upon hydration, the hydrogel core transitions from the dehydrated shape to the hydrated shape.
    Type: Application
    Filed: July 24, 2002
    Publication date: December 5, 2002
    Applicant: Raymedica, Inc.
    Inventors: Charles D. Ray, Robert L. Assell
  • Patent number: 6193706
    Abstract: A guidewire extension system including a guidewire and an extension wire is disclosed. The system includes female and male connector segments located on the proximal end of the guidewire or the distal end of the extension wire. The hollow female connector segment, in one embodiment, includes a radial lip which intersects with at least one, i.e., one or more, lateral slots. The male connector segment includes an external groove. When the male connector is inserted into the female connector segment, the slots are expanded and the lip snaps into the groove providing a tactile indication that connection is completed. No restriction or frictional fit is created. The guidewire and extension wire are freely rotatable with respect to each other and can be multiply connected and disconnected. Methods of catheter exchange with tactile indication of guidewire extension wire connection are disclosed.
    Type: Grant
    Filed: August 16, 1996
    Date of Patent: February 27, 2001
    Assignee: Lake Region Manufacturing Co., Inc.
    Inventors: Michael S. Thorud, Robert L. Assell, Victor R. Blackledge
  • Patent number: 6132465
    Abstract: A wedge-shaped prosthetic spinal disc nucleus including a hydrogel core surrounded by a constraining jacket. The hydrogel core is preshaped to form the wedge shape in a hydrated state. The constraining jacket is flexible, but substantially inelastic and is configured to prevent the hydrogel core from conforming to an anulus upon hydration. The prosthetic spinal disc nucleus corresponds generally to anatomical variations in disc space geometry, generally defined by separable areas or compartments, thus improving performance. In one preferred embodiment, the prosthetic spinal disc nucleus includes a radiopaque marker for indicating a location and orientation following implant.
    Type: Grant
    Filed: June 4, 1998
    Date of Patent: October 17, 2000
    Assignee: Raymedica, Inc.
    Inventors: Charles D. Ray, Robert L. Assell
  • Patent number: 6113639
    Abstract: A trial implant for evaluating a size of an intradiscal space for subsequent implantation of a prosthetic spinal disc nucleus. The trial implant is comprised of an elongated central body and a retrieving body. The elongated body is formed from a rigid, surgically safe material and preferably has a volume less than a volume of a nucleus cavity portion of the intradiscal space. The retrieving body is associated with the central body and is configured to facilitate retrieval of the trial implant from an enclosed area, such as the nucleus cavity. A plurality of trial implants are included with a trial implant kit, with each of the plurality of trial implants housing a different size and/or shape. During use, the trial implant provides an indication as to whether a similarly sized prosthetic spinal disc nucleus will fit within a particular intradiscal space.
    Type: Grant
    Filed: March 23, 1999
    Date of Patent: September 5, 2000
    Assignee: Raymedica, Inc.
    Inventors: Charles D. Ray, Robert L. Assell
  • Patent number: 6022376
    Abstract: A capsule-shaped prosthetic spinal disc nucleus for implantation into a human intradiscal space, made of a substantially inelastic constraining jacket surrounding an amorphous polymer core. The constraining jacket has a generally fixed maximum volume and defines a height. The amorphous polymer core fills an initial volume of the constraining jacket and develops an internal pressure. In response to the internal pressure, the constraining jacket transitions toward the maximum volume, increasing substantially in height.
    Type: Grant
    Filed: March 16, 1998
    Date of Patent: February 8, 2000
    Assignee: RayMedica, Inc.
    Inventors: Robert L. Assell, Charles D. Ray
  • Patent number: 5824093
    Abstract: An elongated, capsule shaped prosthetic spinal disc nucleus body for implantation into a human inter vertebral spinal disc, made of a hydrogel core and a constraining jacket surrounding the hydrogel core that permits the hydrogel core to deform and reform. The constraining jacket is configured to allow the hydrogel core to hydrate to a predetermined volume and will deform and reform in a desired fashion in response to various loads placed upon the spinal tract. The prosthetic spinal disc nucleus assists in restoring the natural physiology of the human intervertebral disc. By implanting two prosthetic spinal disc nuclei side-by-side into a damaged disc of a human spine, both height and motion can be maintained.
    Type: Grant
    Filed: June 6, 1997
    Date of Patent: October 20, 1998
    Assignee: RayMedica, Inc.
    Inventors: Charles D. Ray, Eugene A. Dickhudt, Robert L. Assell
  • Patent number: 5546958
    Abstract: A guidewire extension system including a guidewire and an extension wire is disclosed. The system includes female and male connector segments located on the proximal end of the guidewire or the distal end of the extension wire. The hollow female connector segment, in one embodiment, includes a radial lip which intersects with lateral slots. The male connector segment includes an external groove. When the male connector is inserted into the female connector segment, the slots are expanded and the lip snaps into the groove providing a tactile indication that connection is completed.No restriction or frictional fit is created. The guidewire and extension wire are freely rotatable with respect to each other and can be multiply connected and disconnected. Methods of catheter exchange with tactile indication of guidewire extension wire connection are disclosed.
    Type: Grant
    Filed: March 31, 1994
    Date of Patent: August 20, 1996
    Assignee: Lake Region Manufacturing Company, Inc.
    Inventors: Michael S. Thorud, Robert L. Assell
  • Patent number: 5273802
    Abstract: The present invention relates to novel orthopedic casting materials having superior layer to layer lamination, and methods for preparing the same. The orthopedic casting materials comprise a resin-coated scrim having a plurality of projections along at least one surface thereof. Preferably, each projection comprises a bundle of at least about 8 filaments, and the scrim has from about 75 to about 1500 projections per gram of scrim. The projections serve to mechanically interact with adjacent layers of the material, thereby significantly enhancing the lamination properties of the resultant material and resisting delamination once the material has cured.
    Type: Grant
    Filed: July 7, 1989
    Date of Patent: December 28, 1993
    Assignee: Minnesota Mining and Manufacturing Company
    Inventors: Matthew T. Scholz, Ralph A. Wilkens, Robert L. Assell, Charles E. Alexson
  • Patent number: 4901712
    Abstract: A bone nailer adapted for use with an elongate nail or screw like insert that has a head portion, and a smaller diameter embedable portion projecting from the head portion. The nailer includes a housing having an inner surface defining a through passageway with a portion of the inner surface adjacent an outlet opening of the passageway being adapted to receive the insert with its head portion farthest from the outlet opening and to guide the head portion during movement of the insert through the outlet opening.
    Type: Grant
    Filed: April 22, 1988
    Date of Patent: February 20, 1990
    Assignee: Minnesota Mining and Manufacturing Company
    Inventors: Douglas W. Voegell, Robert L. Assell