Patents by Inventor Ramaswamy Lakshminarayanan

Ramaswamy Lakshminarayanan 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).

  • Publication number: 20130030531
    Abstract: An improved bone graft is provided for human implantation, particularly such as a spinal fusion cage for implantation into the inter-vertebral space between two adjacent vertebrae. The improved spinal fusion cage includes a substrate block of high strength biocompatible material having a selected size and shape to fit the anatomical space, and a controlled porosity analogous to natural bone. The substrate block may be coated with a bio-active surface coating material such as hydroxyapatite or a calcium phosphate to promote bone ingrowth and enhanced bone fusion. Upon implantation, the fusion cage provides a spacer element having a desired combination of mechanical strength together with osteoconductivity and osteoinductivity to promote bone ingrowth and fusion, as well as radiolucency for facilitated post-operative monitoring. The fusion cage may additionally carry one or more natural or synthetic therapeutic agents for further promoting bone ingrowth and fusion.
    Type: Application
    Filed: June 29, 2012
    Publication date: January 31, 2013
    Applicant: Amedica Corporation
    Inventors: Darrel S. Brodke, Bret M. Berry, Ashok C. Khandkar, Ramaswamy Lakshminarayanan, Mahendra S. Rao
  • Publication number: 20120330420
    Abstract: An improved implant is provided for human implantation, such as a spinal implant for implantation into the intervertebral space between two adjacent vertebrae. Some embodiments include a substrate of high strength biocompatible material, such as doped silicon nitride ceramic for example. In some embodiments, the substrate may also include one or more regions of a controlled porosity analogous to natural bone. In other embodiments, the substrate may comprise the entire implant.
    Type: Application
    Filed: May 10, 2012
    Publication date: December 27, 2012
    Applicant: Amedica Corporation
    Inventors: Darrel S. Brodke, Bret M. Berry, Ashok C. Khandkar, Ramaswamy Lakshminarayanan, Mahendra S. Rao
  • Publication number: 20120136454
    Abstract: An improved hlp prosthesis includes an acetabular cup bearing component constructed from a relatively hard and high strength ceramic material for articulation with a ball-shaped femoral head component which may be constructed from a compatible ceramic or metal material. In one form, the acetabular cup further includes a ceramic porous bone ingrowth surface adhered thereto for secure ingrowth attachment to natural patient bone.
    Type: Application
    Filed: February 8, 2012
    Publication date: May 31, 2012
    Applicant: Amedica Corporation
    Inventors: K. Scott Ely, Ashok C. Khandkar, Ramaswamy Lakshminarayanan, Aaron A. Hofmann
  • Publication number: 20120123545
    Abstract: A total disc implant (TDI) is provided for total replacement of a spinal disc or discs in a human patient or other mammal, wherein the TDI is designed to maintain a substantially full range of natural motion (ROM) following implantation. The TDI generally comprises, in one preferred form, upper and lower end plates for affixation to adjacent vertebral bodies, with an intervening insert disposed therebetween. The end plates each include elongated part-cylindrical surfaces oriented generally perpendicular to each other, with one of said surfaces extending in an anterior-posterior direction and the other extending in a medial-lateral direction. The intervening insert defines concave upper and lower part-cylindrical seats oriented for respectively engaging these part-cylindrical surfaces, wherein these part-cylindrical seats are defined by offset radii to include a somewhat flattened central base region merging smoothly with upwardly curving radiused sides.
    Type: Application
    Filed: August 11, 2011
    Publication date: May 17, 2012
    Applicant: Amedica Corporation
    Inventors: Ashok C. Khandkar, Darrel S. Brodke, Ramaswamy Lakshminarayanan
  • Patent number: 8133284
    Abstract: An improved hip prosthesis includes an acetabular cup bearing component constructed from a relatively hard and high strength ceramic material for articulation with a ball-shaped femoral head component which may be constructed from a compatible ceramic or metal material. In one form, the acetabular cup further includes a ceramic porous bone ingrowth surface adhered thereto for secure ingrowth attachment to natural patient bone.
    Type: Grant
    Filed: March 26, 2010
    Date of Patent: March 13, 2012
    Assignee: Amedica Corporation
    Inventors: K. Scott Ely, Ashok C. Khandkar, Ramaswamy Lakshminarayanan, Aaron A. Hofmann
  • Patent number: 8016890
    Abstract: A total disc implant (TDI) is provided for total replacement of a spinal disc or discs in a human patient or other mammal, wherein the TDI is designed to maintain a substantially full range of natural motion (ROM) following implantation. The TDI generally comprises, in one preferred form, upper and lower end plates for affixation to adjacent vertebral bodies, with an intervening insert disposed therebetween. The end plates each include elongated part-cylindrical surfaces oriented generally perpendicular to each other, with one of said surfaces extending in an anterior-posterior direction and the other extending in a medial-lateral direction. The intervening insert defines concave upper and lower part-cylindrical seats oriented for respectively engaging these part-cylindrical surfaces, wherein these part-cylindrical seats are defined by offset radii to include a somewhat flattened central base region merging smoothly with upwardly curving radiused sides.
    Type: Grant
    Filed: July 7, 2010
    Date of Patent: September 13, 2011
    Assignee: Amedica Corporation
    Inventors: Ashok C. Khandkar, Darrel S. Brodke, Ramaswamy Lakshminarayanan
  • Publication number: 20110098818
    Abstract: An improved bone graft is provided for human implantation, particularly such as a spinal fusion cage for implantation into the inter-vertebral space between two adjacent vertebrae. The improved spinal fusion cage includes a substrate block of high strength biocompatible material having a selected size and shape to fit the anatomical space, and a controlled porosity analogous to natural bone. The substrate block may be coated with a bio-active surface coating material such as hydroxyapatite or a calcium phosphate to promote bone ingrowth and enhanced bone fusion. Upon implantation, the fusion cage provides a spacer element having a desired combination of mechanical strength together with osteoconductivity and osteoinductivity to promote bone ingrowth and fusion, as well as radiolucency for facilitated post-operative monitoring. The fusion cage may additionally carry one or more natural or synthetic therapeutic agents for further promoting bone ingrowth and fusion.
    Type: Application
    Filed: May 10, 2010
    Publication date: April 28, 2011
    Inventors: Darrel S. Brodke, Bret M. Berry, Ashok C. Khandkar, Ramaswamy Lakshminarayanan, Mahendra S. Rao
  • Publication number: 20110046741
    Abstract: A total disc implant (TDI) is provided for total replacement of a spinal disc or discs in a human patient or other mammal, wherein the TDI is designed to maintain a substantially full range of natural motion (ROM) following implantation. The TDI generally comprises, in one preferred form, upper and lower end plates for affixation to adjacent vertebral bodies, with an intervening insert disposed therebetween. The end plates each include elongated part-cylindrical surfaces oriented generally perpendicular to each other, with one of said surfaces extending in an anterior-posterior direction and the other extending in a medial-lateral direction. The intervening insert defines concave upper and lower part-cylindrical seats oriented for respectively engaging these part-cylindrical surfaces, wherein these part-cylindrical seats are defined by offset radii to include a somewhat flattened central base region merging smoothly with upwardly curving radiused sides.
    Type: Application
    Filed: July 7, 2010
    Publication date: February 24, 2011
    Applicant: Amedica Corporation
    Inventors: Ashok C. Khandkar, Darrel S. Brodke, Ramaswamy Lakshminarayanan
  • Publication number: 20100228354
    Abstract: An improved hip prosthesis includes an acetabular cup bearing component constructed from a relatively hard and high strength ceramic material for articulation with a ball-shaped femoral head component which may be constructed from a compatible ceramic or metal material. In one form, the acetabular cup further includes a ceramic porous bone ingrowth surface adhered thereto for secure ingrowth attachment to natural patient bone.
    Type: Application
    Filed: March 26, 2010
    Publication date: September 9, 2010
    Applicant: Amedica Corporation
    Inventors: K. Scott Ely, Ashok C. Khandhar, Ramaswamy Lakshminarayanan, Aaron A. Hofmann
  • Patent number: 7780738
    Abstract: A ceramic-metal composite articulation is provided with substantial elimination of wear debris, wherein a ceramic material is provided with superior mechanical properties tailored for articulating with ceramic articulations having high flexural strength (greater than about 700 MPa), high fracture toughness (greater than about 7 MPam1/2) and a high Weibull modulus (greater than about 20), in comparison with presently available bio-ceramics such as alumina or zirconia. The mechanical property enhancement enables ceramic materials with greater reliability and significantly reduced in-vivo fracture risk to be obtained. Preliminary in-vitro wear performance, to several million cycles using established test protocols, of head/cup components in a prosthetic hip joint made from these ceramics also demonstrates the ultra low wear characteristics.
    Type: Grant
    Filed: December 21, 2004
    Date of Patent: August 24, 2010
    Assignee: Amedica Corporation
    Inventors: Ashok C. Khandkar, Aaron A. Hofmann, Ramaswamy Lakshminarayanan
  • Patent number: 7776085
    Abstract: An improved knee prosthesis includes a ceramic tibial component for articulation with natural or prosthetic (re-surfaced) femoral surfaces. The ceramic tibial component is provided in the form of a ceramic monoblock adapted for fixation relative to the patient's tibial bone, or alternately in the form of a ceramic bearing insert component carried by a tibial baseplate member which is adapted in turn for fixation relative to tibial bone. In either form, the ceramic tibial component includes at least one upwardly concave articulation surface for movable bearing engagement by a generally convex or condylar shaped femoral articulation surface. The ceramic tibial component provides improved wear characteristics with extended service life.
    Type: Grant
    Filed: September 8, 2005
    Date of Patent: August 17, 2010
    Assignee: Amedica Corporation
    Inventors: John P. Bernero, Ashok C. Khandkar, Ramaswamy Lakshminarayanan, Aaron A. Hofmann
  • Patent number: 7771481
    Abstract: A total disc implant (TDI) is provided for total replacement of a spinal disc or discs in a human patient or other mammal, wherein the TDI is designed to maintain a substantially full range of natural motion (ROM) following implantation. The TDI generally comprises, in one preferred form, upper and lower end plates for affixation to adjacent vertebral bodies, with an intervening insert disposed therebetween. The end plates each include elongated part-cylindrical surfaces oriented generally perpendicular to each other, with one of said surfaces extending in an anterior-posterior direction and the other extending in a medial-lateral direction. The intervening insert defines concave upper and lower part-cylindrical seats oriented for respectively engaging these part-cylindrical surfaces, wherein these part-cylindrical seats are defined by offset radii to include a somewhat flattened central base region merging smoothly with upwardly curving radiused sides.
    Type: Grant
    Filed: September 19, 2007
    Date of Patent: August 10, 2010
    Assignee: Amedica Corporation
    Inventors: Ashok C. Khandkar, Darrel S. Brodke, Ramaswamy Lakshminarayanan
  • Patent number: 7758646
    Abstract: A total disc implant (TDI) is provided for total replacement of a spinal disc or discs in a human patient or other mammal, wherein the TDI is designed to maintain a substantially full range of natural motion (ROM) following implantation. The TDI generally comprises, in one preferred form, upper and lower end plates for affixation to adjacent vertebral bodies, with an intervening insert disposed therebetween. The end plates each include elongated part-cylindrical surfaces oriented generally perpendicular to each other, with one of said surfaces extending in an anterior-posterior direction and the other extending in a medial-lateral direction. The intervening insert defines concave upper and lower part-cylindrical seats oriented for respectively engaging these part-cylindrical surfaces, wherein these part-cylindrical seats are defined by offset radii to include a somewhat flattened central base region merging smoothly with upwardly curving radiused sides.
    Type: Grant
    Filed: June 9, 2005
    Date of Patent: July 20, 2010
    Assignee: Amedica Corporation
    Inventors: Ashok C. Khandkar, Darrel S. Brodke, Ramaswamy Lakshminarayanan
  • Patent number: 7695521
    Abstract: An improved hip prosthesis includes an acetabular cup bearing component constructed from a relatively hard and high strength ceramic material for articulation with a ball-shaped femoral head component which may be constructed from a compatible ceramic or metal material. In one form, the acetabular cup further includes a ceramic porous bone ingrowth surface adhered thereto for secure ingrowth attachment to natural patient bone.
    Type: Grant
    Filed: August 12, 2005
    Date of Patent: April 13, 2010
    Assignee: Amedica Corporation
    Inventors: K. Scott Ely, Ashok C. Khandkar, Ramaswamy Lakshminarayanan, Aaron A. Hofmann
  • Publication number: 20080033563
    Abstract: A total disc implant (TDI) is provided for total replacement of a spinal disc or discs in a human patient or other mammal, wherein the TDI is designed to maintain a substantially full range of natural motion (ROM) following implantation. The TDI generally comprises, in one preferred form, upper and lower end plates for affixation to adjacent vertebral bodies, with an intervening insert disposed therebetween. The end plates each include elongated part-cylindrical surfaces oriented generally perpendicular to each other, with one of said surfaces extending in an anterior-posterior direction and the other extending in a medial-lateral direction. The intervening insert defines concave upper and lower part-cylindrical seats oriented for respectively engaging these part-cylindrical surfaces, wherein these part-cylindrical seats are defined by offset radii to include a somewhat flattened central base region merging smoothly with upwardly curving radiused sides.
    Type: Application
    Filed: September 19, 2007
    Publication date: February 7, 2008
    Applicant: AMEDICA CORPORATION
    Inventors: Ashok Khandkar, Darrel Brodke, Ramaswamy Lakshminarayanan
  • Publication number: 20060276788
    Abstract: An improved spinal fixation system is provided for human implantation, including a set of screws with interconnecting rods for implantation into the pedicle and between two adjacent vertebrae or a plate with screws for fixating two adjacent vertebrae. The screws, rods, and plates include a substrate portion of high strength biocompatible material and a controlled porosity analogous to natural bone. The substrate portion may be coated with a bio-active surface coating material such as hydroxyapatite or a calcium phosphate to promote bone ingrowth and enhanced bone fusion. Upon implantation, the fixation system provides a desired combination of mechanical strength together with osteoconductivity and bio-activity to promote bone ingrowth and fusion, as well as radiolucency for facilitated post-operative monitoring. The fixation system may additionally carry one or more natural or synthetic therapeutic agents for further promoting bone ingrowth and fusion.
    Type: Application
    Filed: May 26, 2005
    Publication date: December 7, 2006
    Inventors: Bret Berry, Ashok Khandkar, Ramaswamy Lakshminarayanan
  • Publication number: 20060052875
    Abstract: An improved knee prosthesis includes a ceramic tibial component for articulation with natural or prosthetic (re-surfaced) femoral surfaces. The ceramic tibial component is provided in the form of a ceramic monoblock adapted for fixation relative to the patient's tibial bone, or alternately in the form of a ceramic bearing insert component carried by a tibial baseplate member which is adapted in turn for fixation relative to tibial bone. In either form, the ceramic tibial component includes at least one upwardly concave articulation surface for movable bearing engagement by a generally convex or condylar shaped femoral articulation surface. The ceramic tibial component provides improved wear characteristics with extended service life.
    Type: Application
    Filed: September 8, 2005
    Publication date: March 9, 2006
    Inventors: John Bernero, Ashock Khandkar, Ramaswamy Lakshminarayanan, Aaron Hofmann
  • Patent number: 6994727
    Abstract: A total disc implant (TDI) is provided for total replacement of a spinal disc or discs in a human patient or other mammal, wherein the TDI is designed to maintain a substantially full range of natural motion (ROM) following implantation. The TDI generally comprises, in one preferred form, upper and lower end plates for affixation to adjacent vertebral bodies, with an intervening insert disposed therebetween. The end plates each include elongated part-cylindrical surfaces oriented generally perpendicular to each other, with one of said surfaces extending in an anterior-posterior direction and the other extending in a medial-lateral direction. The intervening insert defines concave upper and lower part-cylindrical seats oriented for respectively engaging these part-cylindrical surfaces, wherein these part-cylindrical seats are defined by offset radii to include a somewhat flattened central base region merging smoothly with upwardly curving radiused sides.
    Type: Grant
    Filed: December 15, 2003
    Date of Patent: February 7, 2006
    Assignee: Amedica Corporation
    Inventors: Ashok C. Khandkar, Darrel S. Brodke, Ramaswamy Lakshminarayanan
  • Publication number: 20050273176
    Abstract: An improved hip prosthesis includes an acetabular cup bearing component constructed from a relatively hard and high strength ceramic material for articulation with a ball-shaped femoral head component which may be constructed from a compatible ceramic or metal material. In one form, the acetabular cup further includes a ceramic porous bone ingrowth surface adhered thereto for secure ingrowth attachment to natural patient bone.
    Type: Application
    Filed: August 12, 2005
    Publication date: December 8, 2005
    Inventors: K. Ely, Ashok Khandkar, Ramaswamy Lakshminarayanan, Aaron Hofmann
  • Publication number: 20050240273
    Abstract: A total disc implant (TDI) is provided for total replacement of a spinal disc or discs in a human patient or other mammal, wherein the TDI is designed to maintain a substantially full range of natural motion (ROM) following implantation. The TDI generally comprises, in one preferred form, upper and lower end plates for affixation to adjacent vertebral bodies, with an intervening insert disposed therebetween. The end plates each include elongated part-cylindrical surfaces oriented generally perpendicular to each other, with one of said surfaces extending in an anterior-posterior direction and the other extending in a medial-lateral direction. The intervening insert defines concave upper and lower part-cylindrical seats oriented for respectively engaging these part-cylindrical surfaces, wherein these part-cylindrical seats are defined by offset radii to include a somewhat flattened central base region merging smoothly with upwardly curving radiused sides.
    Type: Application
    Filed: June 9, 2005
    Publication date: October 27, 2005
    Inventors: Ashock Khandkar, Darrel Brodke, Ramaswamy Lakshminarayanan