48 results about "Total joint replacement" patented technology

A method and system for performing a total joint arthroplasty procedure on a patient's damaged bone region. A CT image or other suitable image is formed of the damaged bone surfaces, and location coordinate values (xn,yn,zn) are determined for a selected sequence of bone surface locations using the CT image data. A mathematical model z=f(x,y) of a surface that accurately matches the bone surface coordinates at the selected bone spice locations, or matches surface normal vector components at selected bone surface locations, is determined. The model provides a production file from which a cutting jig and an implant device (optional), each patient-specific and having controllable alignment, are fabricated for the damaged bone by automated processing. At this point, the patient is cut open (once), the cutting jig and a cutting instrument are used to remove a selected portion of the bone and to provide an exposed planar surface, the implant device is optionally secured to and aligned with the remainder of the bone, and the patient's incision is promptly repaired.

Disclosed herein is a method of generating a computerized bone model representative of at least a portion of a patient bone in a pre-degenerated state. The method includes: generating at least one image of the patient bone in a degenerated state; identifying a reference portion associated with a generally non-degenerated portion of the patient bone; identifying a degenerated portion associated with a generally degenerated portion of the patient bone; and using information from at least one image associated with the reference portion to modify at least one aspect associated with at least one image associated the generally degenerated portion. The method may further include employing the computerized bone model representative of the at least a portion of the patient bone in the pre-degenerated state in defining manufacturing instructions for the manufacture of a customized arthroplasty jig. Also disclosed herein is a customized arthroplasty jig manufactured according to the above-described method. The customized arthroplasty jig is configured to facilitate a prosthetic implant restoring a patient joint to a natural alignment. The prosthetic implant may be for a total joint replacement or partial joint replacement. The patient joint may be a variety of joints, including, but not limited to, a knee joint.

A system and method used in total joint arthroplasty of a ball and socket joint such as hip and shoulder replacements for accurate positioning of a prosthesis through pinless surgical navigation during replacement surgery according to a predetermined distance from the center of rotation of the replaced joint and / or articular surface to obtain the proper length, offset, and biomechanics of the replaced joint.

An endoprosthetic joint implant includes a fixation element and a hydrogel hinge portion. The fixation element supports the hydrogel hinge portion on a resected bone-end, for example, for use in surgical joint replacement. The fixation element of one embodiment features a stem made of titanium. The stem is threaded for insertion distally into an intramedullary canal. The hydrogel hinge portion connects to the stem using a snap-fit arrangement. The hydrogel is available in various surface configurations and can articulate against a natural joint surface or a synthetic joint surface. A total joint-replacement implant is provided by attaching a second stem to an opposite side of the hinge for insertion into bone on the opposed side of the articulation.

Disclosed are implantable devices that include biocompatible polyurethane materials. In particular, the disclosed polyurethane materials can maintain desired elastomeric characteristics while exhibiting thermoset-like behavior and can exhibit improved characteristics so as to be suitable in load-bearing applications. For example, the disclosed polyurethane materials can be suitable for use in artificial joints, including total joint replacement applications. The disclosed polyurethane materials include biocompatible cross-linking agents as chain extenders, more particularly chain extenders comprising a terminal group capable of side reactions and further comprising an electron withdrawing group immediately adjacent the terminal group. In addition, the reaction materials and conditions can be selected to encourage intermediate levels of cross-linking without the use of traditional cross-linking trifunctional reagents. In addition, the chain extenders can also include substantially inflexible moieties so as to increase the rigidity of the product polyurethanes.

The present invention relates to limited incision total joint replacement methods for performing surgery on a joint in a patient's body, such as a knee. In one embodiment, an incision is made in a knee portion of one leg while a lower portion of the one leg is extending downward from an upper portion of the one leg and while a foot connected with the lower portion of the one leg is below a support surface on which the patient is disposed. The incision is relatively short, for example, between seven and thirteen centimeters. A patella may be offset from its normal position with an inner side of the patella facing inward during cutting of a bone with a cutting tool. During cutting of the bone, one or more guide members having opposite ends which are spaced apart by a distance less than the width of an implant may be utilized to guide movement of a cutting tool.

A prosthetic implant for the body having an associated gyroscope, accelerometer and / or magnetometer as the sensor to detect changes in position of the implant. The device incorporates a miniature gyroscope, accelerometer, and / or magnetometer as a permanent part of the prosthesis for navigational information. Alternatively, the magnetometer can be external to the implant when the implant has magnetic elements associated with it. The sensors can be microelectromechanical system (MEMS) sensors placed within a drilled hole and sealed with a screw or a cap (20). The implant can be responsive to an external interrogation and powering systems. The device provides information so as to help to properly place the prosthetic implant during surgery and to assess proper functioning. The gyroscope, accelerometer, and / or magnetometer are used after implantation to provide diagnostic information in situ based upon the changed positioning or motion of the device in the prosthesis. The device can be a total joint replacement, dental implant or other type of prosthetic implant.

The present invention provides an arthroplasty supporting information calculation method for supporting diagnoses of a patient with knee disordered and total joint replacement to a total knee component, and an arthroplasty supporting information calculation program, and an arthroplasty supporting information calculation system. In an arthroplasty supporting terminal of the present invention, photographed X-ray images are acquired using X-ray irradiation mechanisms and a dedicated cassette base, Approximate three-dimensional data of a patient's bones is then created by transforming a display image of three-dimensional data of CT of the patient and / or sample bones to match the X-ray image in which the patient's bones are photographed. Three-dimensional coordinate values are then determined for this approximate three-dimensional data of the patient's bones. From these three-dimensional coordinate values, parameters are determined for evaluating positional relationships between at least two bones. The position of the display image of the three-dimensional data of a total knee component is then adjusted to match the display image of the approximate three-dimensional data of the patient's bones based on the three-dimensional coordinate values. The position of the total knee component is then calculated as anatomical coordinate values that represent the positions of at least two bones.

Methods and systems are described to quantitatively determine the degree of soft tissue constraints on knee ligaments and for properly determining placement parameters for prosthetic components in knee replacement surgery that will minimize strain on the ligaments. In one aspect, a passive kinetic manipulation technique is used in conjunction with a computer aided surgery (CAS) system to accurately and precisely determine the length and attachment sites of ligaments. These manipulations are performed after an initial tibial cut and prior to any other cuts or to placement of any prosthetic component. In a second aspect, a mathematical model of knee kinematics is used with the CAS system to determine optimal placement parameters for the femoral and tibial components of the prosthetic device that minimizes strain on the ligaments.

A trapezium prosthesis is provided for replacement of a diseased trapezium of a hand. Also shown is a surgical technique for placement of the prosthesis. Rather than utilizing hemiarthoplasty or total joint replacement, the trapezium is replaced with the prosthesis made of a material other than silicon. The prosthesis has specially prepared surfaces to encourage the growth and attachment of surrounding tissue.

Disclosed herein is a method of generating a computerized bone model representative of at least a portion of a patient bone in a pre-degenerated state. The method includes: generating at least one image of the patient bone in a degenerated state; identifying a reference portion associated with a generally non-degenerated portion of the patient bone; identifying a degenerated portion associated with a generally degenerated portion of the patient bone; and using information from at least one image associated with the reference portion to modify at least one aspect associated with at least one image associated the generally degenerated portion. The method may further include employing the computerized bone model representative of the at least a portion of the patient bone in the pre-degenerated state in defining manufacturing instructions for the manufacture of a customized arthroplasty jig. Also disclosed herein is a customized arthroplasty jig manufactured according to the above-described method. The customized arthroplasty jig is configured to facilitate a prosthetic implant restoring a patient joint to a natural alignment. The prosthetic implant may be for a total joint replacement or partial joint replacement. The patient joint may be a variety of joints, including, but not limited to, a knee joint.

Disclosed is a kit having a set of humeral components used in partial and total joint replacement surgeries. The set of humeral components has a plurality of stems having varying stem diameters and a set of humeral heads having hemispheric surfaces with varying radiuses. Each stem defines a platform having a hole which is a fixed distance from the proximal end of the stem. The distance of the hole from the proximal end of the stem is a function of the stem diameter.

The invention reduces wear in total joint articulations by modifications of the shape of either component of the kinematic pair, so as to result in an annular surface contact between the two components. Fluid trapped between the two components within the inner contour of the annular contact area is pressurized under load due to elastic deformation of the components and exuded out through inter-articular gap over the surface of contact, aiding in lubrication and reducing the wear. Reduced to practice for a total hip joint with UHMWPE-metal pair, the wear rate tested in a hip joint simulator up to five million cycles was reduced by factor seven to fifteen compared to conventionally shaped components.

An apparatus has been developed to enable a surgeon to perform multiple orthopedic surgical operations, such as orthopedic surgical resectioning, total joint replacement and fixation of fractures, based on a single reference point. The apparatus is adjustable to conform to the needs and dimensions of individual patients and the surgical procedure(s) to be performed. The apparatus includes a support adapted for insertion into and alignment within the medullary cavity of a patient's bone. The support is capable of expanding into the bone so that the support is fixed within the bone and alignable to the bone. The support may be implanted to align a fractured bone, or extend a distance beyond its fixed position within the medullary cavity to provide a known surgical reference point. The apparatus includes one or more cutting guides mountable on the support and used in performing the desired surgical procedure(s). The cutting guides are positionable with respect to the known surgical reference point created by the support which enables the user to accurately position and secure various instruments at the desired position about the patient's anatomy.

A method and apparatus for minimally invasive total joint replacement is disclosed. The method involves sculpting the articular surface of a second bone that normally articulates with a first bone by attaching or supporting a bone sculpting tool directly or indirectly to the first bone with the tool in sculpting engagement with the articular surface of the second bone, and then sculpting the articular surface of the second bone with the joint reduced. The reamer system includes a reamer drive, a grater, a handle and a femoral broach.

Natural joint interfaces wear out and / or are damaged causing pain and disability. They can be currently replaced by artificial surfaces made of materials or in the near future by magnetic fields. They would benefit from a PVES (paramagnetic visco-viscoelastic supplement) that can replace or augment natural joint interfaces or augment total joint replacements. Joint replacement components can be modular and would benefit from a PVES to decrease wear and damp impact between modular parts of a single component. The PVES is a dynamic interface allowing components to be less rigid. Energy transmission is reduced. PVES can act as an interface between natural damaged joint surfaces obviating the need for classic total joint replacement or between the surfaces of artificial joint components to improve or supplement their function. These PVES can be controlled by magnetic fields with respect to their location, physical properties, loads, etc. PVES are typically made of paramagnetic ions and a substrate molecule. One such PVES can be made of gadolinium ions and hyaluronic acid to form gadolinium hyaluronate.

The invention reduces wear in total joint articulations by modifications of the shape of either component of the kinematic pair, so as to result in an annular surface contact between the two components. Fluid trapped between the two components within the inner contour of the annular contact area is pressurized under load due to elastic deformation of the components and exuded out through inter-articular gap over the surface of contact, aiding in lubrication and reducing the wear. Reduced to practice for a total hip joint with UHMWPE-metal pair, the wear rate tested in a hip joint simulator up to five million cycles was reduced by factor seven to fifteen compared to conventionally shaped components.

A method and apparatus for minimally invasive total joint replacement. The method involves sculpting the articular surface of a second bone that normally articulates with a first bone by attaching a bone sculpting tool directly or indirectly to the first bone with the tool in bone sculpting engagement with the articular surface of the second bone, and then sculpting the articular surface of the second bone with the joint reduced and moving one bone with respect to the other. An implant is placed to replace the articular surface of the second bone using an impaction device directly or indirectly attached to the first bone, wherein the force to place the implant is reacted by the second bone and the first bone.

An article of manufacture for load bearing medical use such as a joint implant suitable for total joint replacement. The article comprises a polyurethane-containing component and is monolithic with respect to polyurethane-containing component(s). The joint for long term load applications is structurally an articulated joint and the polyurethane component provides a surface for articulation with the polyurethane.

A variable stiffness stem component for intramedullary fixation in total joint replacement implants or in a segmental replacement system. The stem component has a shaft with a proximal end, a distal end, and a longitudinal length therebetween. The diameter of the shaft is approximately constant along the longitudinal length. A taper or threaded connection may be provided adjacent the proximal end of the shaft for assembly to another implant component. At least three flutes are disposed in a portion of the length of the shaft from intermediate the proximal and distal ends extending towards the distal end. The flutes increase in one of width or depth, or a combination thereof, towards the distal end to provide variable stiffness.

A method and system for performing a total joint arthroplasty procedure on a patient's damaged bone region. A CT image or other suitable image is formed of the damaged bone surfaces, and location coordinate values (xn,yn,zn) are determined for a selected sequence of bone surface locations using the CT image data. A mathematical model z=f(x,y) of a surface that accurately matches the bone surface coordinates at the selected bone spice locations, or matches surface normal vector components at selected bone surface locations, is determined. The model provides a production file from which a cutting jig and an implant device (optional), each patient-specific and having controllable alignment, are fabricated for the damaged bone by automated processing. At this point, the patient is cut open (once), the cutting jig and a cutting instrument are used to remove a selected portion of the bone and to provide an exposed planar surface, the implant device is optionally secured to and aligned with the remainder of the bone, and the patient's incision is promptly repaired.

A method and apparatus for minimally invasive total joint replacement is disclosed. The method involves sculpting the articular surface of a second bone that normally articulates with a first bone by attaching or supporting a bone sculpting tool directly or indirectly to the first bone with the tool in sculpting engagement with the articular surface of the second bone, and then sculpting the articular surface of the second bone with the joint reduced. The reamer system includes a reamer drive, a grater, a handle and a femoral broach.

A process and system for performing orthopaedic surgery with the use of computer systems and robotic assistance to remove bone, bone cement, and a bone prosthesis, typically a bone prosthesis used in hip replacement surgery, knee replacement surgery, and the like. The process for replacing one or more bone prostheses using a robotic system includes receiving image data comprising an image of each bone, including at least one prosthesis implanted within each bone; creating three-dimensional models of the prosthesis, and the bone; creating a plan for positioning new prostheses within the bone; determining the location and amount of bone and any non-bone material to be removed for the new prostheses; and removing the bone prosthesis from the bone. The inventive process may be used for the replacement of hip joints, shoulder joints, ankle joints, wrist joints, finger joints, toe joints, or other joints.

A prosthetic joint is secured to the bones forming the original joint by utilizing strictly mechanical fasteners, for example, a threaded rod engaging a tapped intramedullary canal. Cross locking members may be provided. The need for bone cement is avoided. The prosthetic joint may be used to replace one end of one bone forming the joint, utilizing the naturally occurring end of the other bone. Alternatively, both bone ends may be replaced with prosthetic joint portions. The decision to replace one or both bone ends may be made mid-surgery. The prosthetic joint portions are secured together utilizing ligament reconstruction members made from portions of the patient's tendons or allograft tendons. A bearing forming the interface between the two joint portions is designed to wear in order to protect the remaining components from wear, and to be easily replaced in relatively simple future surgeries.

A system and process for performing orthopedic surgery is provided that uses a patient's existing implant as a registration tool in an orthopedic surgical procedure. The systems and processes may be used with computer assisted systems or navigation systems to aid in the removal of bone, bone cement, or a bone prosthesis, typically a bone prosthesis used in hip replacement surgery, knee replacement surgery, and the like. The removal of the prosthesis may be done by conventional methods, with navigation systems, robotic assistance or articulating hand held systems. The removal of bone and / or bone cement may be performed with navigated systems, robotic systems, articulating hand-held systems and combinations thereof.

An elastomeric artificial joint and prosthesis system combining motion preservation and shock absorption through the interaction of core and endplate components. The core is comprised of: a “hub” having congruent concavity with the endplate surface allowing for rotation, translation, flexion and extension, orbital, lateral bending, and compression motion similar to that of a joint or natural intervertebral disc; a “flange” attached to the hub and able to move congruently with the hub, and having negative spaces providing an internal structure for an elastomer; and a bio-compatible elastomer casted around and through the flange providing shock absorption. The endplate has a low-friction surface and engages the elastomer, and a structural component that engages the vertebral endplate or bone surface. The device has medical applications such as in total joint arthroplasty, disc replacement, and industrial applications such as in robotics that are modeled to move similar to human anatomical motion.

The articulating joint prostheses of the invention demonstrate reduced wear and can include a cup (101) formed of UHMWPE. An insert (150) of a hard material, such as metal, ceramic or cross-linked UHMWPE is positioned within the cup at a location of the contact between the cup and head (102). The shape of either component of the kinematic pair may be modified so as to result in an annular surface contact between the two components, with the insert positioned at the annular surface contact. Fluid trapped between the two components within the inner contour of the annular contact area is pressurized under load due to elastic deformation of the components and exuded out through an inter-articular gap over the surface of contact of the insert. This aids lubrication and reduces wear.

A bearing for a total or partial joint replacement prosthesis: the bearing having a body and a reinforcing element which strengthens the bearing and which forms an attachment member, and / or the bearing being formed at least partially from polymeric or composite material the bearing comprising a lower modulus portion and a higher modulus portion, one portion of the bearing being at least partially encased by the other portion of the bearing. Also provided is a method for of forming the bearing, and a total or partial joint replacement prosthesis comprising the hearing.