Patents by Inventor Chulho Pak

Chulho Pak 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: 20260000431
    Abstract: An external fixation system may include first and second fixation rings and a plurality of adjustable length struts. Each adjustable length strut may have two joints, a rod, a tube, and an actuator configured to drive the rod axially relative to the tube to change an effective length of the strut. The system may include a plurality of controller modules each configured to couple to a corresponding strut. The external fixation system may have a manual mode of operation in which the controller modules are not coupled to the struts, and manual actuation of the actuators changes the effective lengths of the struts in discrete length increments. The external fixation system may have an automated mode of operation in which the controller modules are coupled to the struts, and automated actuation of the actuators changes the effective lengths of the struts in infinitesimally small length increments.
    Type: Application
    Filed: September 18, 2025
    Publication date: January 1, 2026
    Applicant: Stryker European Operations Limited
    Inventors: Chulho Pak, Subash K. Mannanal, Peter Sterrantino, Noah Roberson, Anup Kumar, Andrew J. Nelson
  • Publication number: 20250318859
    Abstract: An adjustable length strut for use in an external fixation system may include an outer tube, an inner tube within the outer tube, and a first adjustment knob. A plurality of texturized surfaces may extend in the length direction of the inner tube, each of the plurality of texturized surfaces of the inner tube being spaced apart from each other in the circumferential direction of the inner tube. Each circumferentially adjacent pair of texturized surfaces of the inner tube is separated by a non-texturized surface. The first adjustment knob may also include texturized surfaces separated by non-texturized surfaces, and may be rotatable relative to the outer tube and the inner tube between a locked condition and an unlocked condition. In the locked condition, the texturized surfaces engage each other, to prevent translation of the inner tube relative to the outer tube.
    Type: Application
    Filed: June 26, 2025
    Publication date: October 16, 2025
    Applicant: Stryker European Operations Limited
    Inventors: Chulho Pak, Subash K. Mannanal
  • Patent number: 12440241
    Abstract: An external fixation system may include first and second fixation rings and a plurality of adjustable length struts. Each adjustable length strut may have two joints, a rod, a tube, and an actuator configured to drive the rod axially relative to the tube to change an effective length of the strut. The system may include a plurality of controller modules each configured to couple to a corresponding strut. The external fixation system may have a manual mode of operation in which the controller modules are not coupled to the struts, and manual actuation of the actuators changes the effective lengths of the struts in discrete length increments. The external fixation system may have an automated mode of operation in which the controller modules are coupled to the struts, and automated actuation of the actuators changes the effective lengths of the struts in infinitesimally small length increments.
    Type: Grant
    Filed: December 19, 2023
    Date of Patent: October 14, 2025
    Assignee: Stryker European Operations Limited
    Inventors: Chulho Pak, Subash K. Mannanal, Peter Sterrantino, Noah Roberson, Anup Kumar, Andrew J. Nelson
  • Patent number: 12364510
    Abstract: An adjustable length strut for use in an external fixation system may include an outer tube, an inner tube within the outer tube, and a first adjustment knob. A plurality of texturized surfaces may extend in the length direction of the inner tube, each of the plurality of texturized surfaces of the inner tube being spaced apart from each other in the circumferential direction of the inner tube. Each circumferentially adjacent pair of texturized surfaces of the inner tube is separated by a non-texturized surface. The first adjustment knob may also include texturized surfaces separated by non-texturized surfaces, and may be rotatable relative to the outer tube and the inner tube between a locked condition and an unlocked condition. In the locked condition, the texturized surfaces engage each other, to prevent translation of the inner tube relative to the outer tube.
    Type: Grant
    Filed: November 22, 2022
    Date of Patent: July 22, 2025
    Assignee: Stryker European Operations Limited
    Inventors: Chulho Pak, Subash K. Mannanal
  • Publication number: 20240390072
    Abstract: A system for treating tissue of a patient's anatomy at a target site. A localizer generates location data associated with the anatomy. A display unit overlays visual content on the anatomy within a field of view observable by a user. A visualization program on a computing device generates a virtual reference frame, identifies viable and non-viable approaches for fixation elements to engage tissue and secure a stabilizer relative to the target site based on patient-specific imaging data, arranges a virtual viability model within the virtual reference frame based on the location data and comprising viable portions associated with viable approaches and non-viable portions associated with non-viable approaches, and renders the virtual viability model in the visual content displayed by the display unit overlaid onto the anatomy within the field of view to assist the user in visualizing at least one of viable approaches and non-viable approaches.
    Type: Application
    Filed: August 7, 2024
    Publication date: November 28, 2024
    Applicant: Stryker European Operations Limited
    Inventors: Ulrich Spaelter, Matthias Paulisch, Fabian Huegle, Rose Riemer, Alexis Christen, Andreas Wiederkehr, Katja Stucki, Pierre-Luc Sylvestre, Subash K. Mannanal, Chulho Pak
  • Patent number: 12137981
    Abstract: A system for treating tissue of a patient's anatomy at a target site. A localizer generates location data associated with the anatomy. A display unit overlays visual content on the anatomy within a field of view observable by a user. A visualization program on a computing device generates a virtual reference frame, identifies viable and non-viable approaches for fixation elements to engage tissue and secure a stabilizer relative to the target site based on patient-specific imaging data, arranges a virtual viability model within the virtual reference frame based on the location data and comprising viable portions associated with viable approaches and non-viable portions associated with non-viable approaches, and renders the virtual viability model in the visual content displayed by the display unit overlaid onto the anatomy within the field of view to assist the user in visualizing at least one of viable approaches and non-viable approaches.
    Type: Grant
    Filed: April 25, 2022
    Date of Patent: November 12, 2024
    Assignee: Stryker European Operations Limited
    Inventors: Ulrich Spaelter, Matthias Paulisch, Fabian Huegle, Rose Riemer, Alexis Christen, Andreas Wiederkehr, Katja Stucki, Pierre-Luc Sylvestre, Subash K. Mannanal, Chulho Pak
  • Publication number: 20240358378
    Abstract: A method of utilizing a distractor in a joint replacement procedure is provided. The method includes releasably engaging a datum to a datum securement of the distractor and gripping a handle of the distractor in an insertion position. The handle includes a first handle portion and a second handle portion. The method includes disposing a paddle of a tissue engaging portion of the distractor against a tissue surface and adjusting the handle from the insertion position to the distraction position to thereby independently move the paddle with respect to both the second handle portion and the first handle portion such that the paddle remains at a generally constant angle against the tissue surface as the tissue surface is distracted. The paddle is attached directly and exclusively to a distal tip of the second handle portion such that the paddle pivots about an axis transverse to a length of the handle.
    Type: Application
    Filed: May 6, 2024
    Publication date: October 31, 2024
    Inventors: Thomas Loring, Stephen G. Gilbert, Chulho Pak, Michael Daniels, Victor Chan
  • Publication number: 20240115294
    Abstract: An external fixation system may include first and second fixation rings and a plurality of adjustable length struts. Each adjustable length strut may have two joints, a rod, a tube, and an actuator configured to drive the rod axially relative to the tube to change an effective length of the strut. The system may include a plurality of controller modules each configured to couple to a corresponding strut. The external fixation system may have a manual mode of operation in which the controller modules are not coupled to the struts, and manual actuation of the actuators changes the effective lengths of the struts in discrete length increments. The external fixation system may have an automated mode of operation in which the controller modules are coupled to the struts, and automated actuation of the actuators changes the effective lengths of the struts in infinitesimally small length increments.
    Type: Application
    Filed: December 19, 2023
    Publication date: April 11, 2024
    Applicant: Stryker European Operations Limited
    Inventors: Chulho Pak, Subash K. Mannanal, Peter Sterrantino, Noah Roberson, Anup Kumar, Andrew J. Nelson
  • Patent number: 11896267
    Abstract: An external fixation system may include first and second fixation rings and a plurality of adjustable length struts. Each adjustable length strut may have two joints, a rod, a tube, and an actuator configured to drive the rod axially relative to the tube to change an effective length of the strut. The system may include a plurality of controller modules each configured to couple to a corresponding strut. The external fixation system may have a manual mode of operation in which the controller modules are not coupled to the struts, and manual actuation of the actuators changes the effective lengths of the struts in discrete length increments. The external fixation system may have an automated mode of operation in which the controller modules are coupled to the struts, and automated actuation of the actuators changes the effective lengths of the struts in infinitesimally small length increments.
    Type: Grant
    Filed: January 27, 2023
    Date of Patent: February 13, 2024
    Assignee: Stryker European Operations Limited
    Inventors: Chulho Pak, Subash K. Mannanal, Peter Sterrantino, Noah Roberson, Anup Kumar, Andrew J. Nelson
  • Publication number: 20240023976
    Abstract: A trial implant is provided. The implant includes a central portion. The central portion includes a top articulating surface extending between a first end and a second end and having a convex shape, a bottom surface configured to at least partially contact a first resected surface of a bone, and a first side surface extending between the top articulating surface and the bottom surface. The first side surface is sloped such that a width of the top articulating surface is greater than a width of the bottom surface. The implant further includes a first outer portion extending laterally from the central portion. The first side surface and the first outer portion are separated by a first opening shaped such that up to four resected surfaces of the bone are visible when the trial implant is seated on the bone.
    Type: Application
    Filed: August 8, 2023
    Publication date: January 25, 2024
    Inventors: Thomas Loring, Chulho Pak, Victor Chan, Ryan Sellman
  • Publication number: 20230255665
    Abstract: An external fixation system may include first and second fixation rings and a plurality of adjustable length struts. Each adjustable length strut may have two joints, a rod, a tube, and an actuator configured to drive the rod axially relative to the tube to change an effective length of the strut. The system may include a plurality of controller modules each configured to couple to a corresponding strut. The external fixation system may have a manual mode of operation in which the controller modules are not coupled to the struts, and manual actuation the actuators changes the effective lengths of the struts in discrete length increments. The external fixation may have an automated mode of operation in which the controller modules are coupled to the struts, and automated actuation of the actuators changes the effective lengths of the struts in infinitesimally small length increments.
    Type: Application
    Filed: January 27, 2023
    Publication date: August 17, 2023
    Applicant: Stryker European Operations Limited
    Inventors: Chulho Pak, Subash K. Mannanal, Peter Sterrantino, Noah Roberson, Anup Kumar, Andrew J. Nelson
  • Patent number: 11723676
    Abstract: A trial implant is provided. The implant includes a central portion. The central portion includes a top articulating surface extending between a first end and a second end and having a convex shape, a bottom surface configured to at least partially contact a first resected surface of a bone, and a first side surface extending between the top articulating surface and the bottom surface. The first side surface is sloped such that a width of the top articulating surface is greater than a width of the bottom surface. The implant further includes a first outer portion extending laterally from the central portion. The first side surface and the first outer portion are separated by a first opening shaped such that up to four resected surfaces of the bone are visible when the trial implant is seated on the bone.
    Type: Grant
    Filed: April 14, 2021
    Date of Patent: August 15, 2023
    Assignee: ENCORE MEDICAL, L.P.
    Inventors: Thomas Loring, Chulho Pak, Victor Chan, Ryan Sellman
  • Publication number: 20230193936
    Abstract: An adjustable length strut for use in an external fixation system may include an outer tube, an inner tube within the outer tube, and a first adjustment knob. A plurality of texturized surfaces may extend in the length direction of the inner tube, each of the plurality of texturized surfaces of the inner tube being spaced apart from each other in the circumferential direction of the inner tube. Each circumferentially adjacent pair of texturized surfaces of the inner tube is separated by a non-texturized surface. The first adjustment knob may also include texturized surfaces separated by non-texturized surfaces, and may be rotatable relative to the outer tube and the inner tube between a locked condition and an unlocked condition. In the locked condition, the texturized surfaces engage each other, to prevent translation of the inner tube relative to the outer tube.
    Type: Application
    Filed: November 22, 2022
    Publication date: June 22, 2023
    Applicant: Stryker European Operations Limited
    Inventors: Chulho Pak, Subash K. Mannanal
  • Publication number: 20220241021
    Abstract: A system for treating tissue of a patient's anatomy at a target site. A localizer generates location data associated with the anatomy. A display unit overlays visual content on the anatomy within a field of view observable by a user. A visualization program on a computing device generates a virtual reference frame, identifies viable and non-viable approaches for fixation elements to engage tissue and secure a stabilizer relative to the target site based on patient-specific imaging data, arranges a virtual viability model within the virtual reference frame based on the location data and comprising viable portions associated with viable approaches and non-viable portions associated with non-viable approaches, and renders the virtual viability model in the visual content displayed by the display unit overlaid onto the anatomy within the field of view to assist the user in visualizing at least one of viable approaches and non-viable approaches.
    Type: Application
    Filed: April 25, 2022
    Publication date: August 4, 2022
    Applicant: Stryker European Operations Limited
    Inventors: Ulrich Spaelter, Matthias Paulisch, Fabian Huegle, Rose Riemer, Alexis Christen, Andreas Wiederkehr, Katja Stucki, Pierre-Luc Sylvestre, Subash K. Mannanal, Chulho Pak
  • Patent number: 11337761
    Abstract: A system for treating tissue of a patient's anatomy at a target site. A localizer generates location data associated with the anatomy. A display unit overlays visual content on the anatomy within a field of view observable by a user. A visualization program on a computing device generates a virtual reference frame, identifies viable and non-viable approaches for fixation elements to engage tissue and secure a stabilizer relative to the target site based on patient-specific imaging data, arranges a virtual viability model within the virtual reference frame based on the location data and comprising viable portions associated with viable approaches and non-viable portions associated with non-viable approaches, and renders the virtual viability model in the visual content displayed by the display unit overlaid onto the anatomy within the field of view to assist the user in visualizing at least one of viable approaches and non-viable approaches.
    Type: Grant
    Filed: February 7, 2020
    Date of Patent: May 24, 2022
    Assignee: Stryker European Operations Limited
    Inventors: Ulrich Spaelter, Matthias Paulisch, Fabian Huegle, Rose Riemer, Alexis Christen, Andreas Wiederkehr, Katja Stucki, Pierre-Luc Sylvestre, Subash K. Mannanal, Chulho Pak
  • Patent number: 11173038
    Abstract: A total ankle prosthesis that includes a talar component that has a bone contacting side for contacting a talus and an articular side opposite the bone contacting side. The articular side has first and second condyles separated by an intercondylar notch. The first condyle defines a spheroidal convex surface. The prosthesis also includes a tibial component that has a bone contacting side for contacting a tibia and an articular side. The articular side has first and second condyles separated by an intercondylar spine. The first condyle of the tibial component defines a concave surface. The concave surface has a condylar edge that defines a perimeter thereof and a plurality of articular portions positioned between anterior and posterior extents of the condylar edge. A first articular portion of the articular portions is spheroidal and a second articular portion is defined by a cylindrical helix.
    Type: Grant
    Filed: February 19, 2020
    Date of Patent: November 16, 2021
    Inventors: Chulho Pak, Subash K. Mannanal, Thomas Loring
  • Publication number: 20210338448
    Abstract: Methods of implanting a talar component during ankle surgery are provided. A method includes cutting at least medial and lateral cuts in a talus bone. The method includes driving a first self-cutting distal edge of a lateral side wall of the talar component into the lateral cut and a second self-cutting distal edge of a medial side wall of the talar component into the medial cut. A thickness of the lateral sidewall tapers to form the first self-cutting distal edge and a thickness of the medial sidewall tapers to form the second self-cutting edge.
    Type: Application
    Filed: May 24, 2021
    Publication date: November 4, 2021
    Inventors: Chulho Pak, Thomas Loring
  • Publication number: 20210298766
    Abstract: A method of utilizing a distractor in a joint replacement procedure is provided. The method includes releasably engaging a datum to a datum securement of the distractor and gripping a handle of the distractor in an insertion position. The handle includes a first handle portion and a second handle portion. The method includes disposing a paddle of a tissue engaging portion of the distractor against a tissue surface and adjusting the handle from the insertion position to the distraction position to thereby independently move the paddle with respect to both the second handle portion and the first handle portion such that the paddle remains at a generally constant angle against the tissue surface as the tissue surface is distracted. The paddle is attached directly and exclusively to a distal tip of the second handle portion such that the paddle pivots about an axis transverse to a length of the handle.
    Type: Application
    Filed: April 20, 2021
    Publication date: September 30, 2021
    Inventors: Thomas Loring, Victor Chan, Chulho Pak, Michael Daniels, Stephen G. Gilbert
  • Publication number: 20210290412
    Abstract: A trial implant is provided. The implant includes a central portion. The central portion includes a top articulating surface extending between a first end and a second end and having a convex shape, a bottom surface configured to at least partially contact a first resected surface of a bone, and a first side surface extending between the top articulating surface and the bottom surface. The first side surface is sloped such that a width of the top articulating surface is greater than a width of the bottom surface. The implant further includes a first outer portion extending laterally from the central portion. The first side surface and the first outer portion are separated by a first opening shaped such that up to four resected surfaces of the bone are visible when the trial implant is seated on the bone.
    Type: Application
    Filed: April 14, 2021
    Publication date: September 23, 2021
    Inventors: Thomas Loring, Chulho Pak, Victor Chan, Ryan Sellman
  • Patent number: 11013607
    Abstract: The present disclosure includes, in one embodiment, a talar component of an ankle joint prosthesis for engagement with a talus bone having a medial side wall and a lateral side wall, opposite the medial side wall, each side wall terminating at a distal edge, and the distal edges adapted to drive into the talus bone. When implanted, the side walls may form a seal between the talus bone and the component to prevent fluid from flowing under the component.
    Type: Grant
    Filed: September 21, 2018
    Date of Patent: May 25, 2021
    Assignee: ENCORE MEDICAL, L.P.
    Inventors: Chulho Pak, Thomas Loring