Abstract: A method for placing a prosthetic acetabular cup within an acetabulum comprises implanting an acetabular cup with an eccentric socket. The acetabular cup may be substantially hemispherical with a cup rim and a portion of the cup rim removed defining a relief. The cup may accommodate a concentric liner in an eccentric position. Screw apertures may be present on the periphery of the cup and the screw trajectories may converge toward the dome of the cup. The cup is attached to a tool which is offset relative to the cup because of the substantially eccentric socket. The relief, when the cup is secured to the acetabulum, is positioned substantially anterior and the socket is positioned more posterior to provide a more natural center of rotation of a femoral head within the socket. The first relief reduces impingement of the acetabular cup on soft tissue.

Abstract: A trial system for an implantable joint replacement includes an articular insert having an insert body and an insert post captive to the insert body. The insert post is translatable relative to the insert body while remaining captive to the insert body. An aperture on the insert body forms a path, which may be arcuate, along which the insert post can translate. An axis of rotation about which the insert post translates passes through the insert body, and may be medially offset from the center of the body. A flexible element may connect the insert post to the insert body. In one method of use, the trial system is engaged with a femoral component and a tibial component during a prosthetic total knee joint implantation procedure to determine selection of an implantable articular insert which provides knee joint articulation closely matching the articulation of a natural knee.

Abstract: Knee prosthesis instrumentation including an insertion tool and a removal tool. The insertion tool may include an offset to provide clearance from a femoral component of the knee prosthesis. The removal tool may be wedge shaped to at least partially encircle a post of the knee prosthesis for removal. A mallet may be used with the instruments to provide additional force for prosthesis insertion or removal. A slide hammer may be incorporated into the instruments themselves.

Abstract: Patient specific implants and instrumentation for replacing a portion of a patella. Methods for producing patient specific implants and instrumentation include conducting imaging studies of the patient's native patella, deriving measurements of the patella and surrounding soft tissues from the imaging studies, manufacturing customized implants and instrumentation specific to the derived measurements, and implanting a customized implant using the customized instrumentation. Patient specific instrumentation includes: a patellar clamp ring, an anterior clamp, a restraining arm, a posterior clamping surface, a dual bore reaming collet, a reamer, a reaming depth gauge, and a resection cutting guide. Patient specific portions of a patellar implant include: topography of the posterior articular surface, facet angle, shape and dimensions of the anterior attachment surface, implant length, implant width, implant thickness and the outer perimeter shape of the implant.

Abstract: A trial system for an implantable joint replacement includes a guide assembly having a baseplate and a guide plate, the guide plate translatable relative to the base plate along a straight path while directly connected to the baseplate. A first adjustment mechanism may selectively control the translational juxtaposition of the guide plate relative to the baseplate. The guide plate may further be rotatable relative to the baseplate around a rotation axis. A second adjustment mechanism may selectively control the rotational juxtaposition of the guide plate relative to the baseplate, and can lock the plates together. The rotation axis may be medially offset from the center of the guide assembly. The guide plate provides in situ positionable cutting guidance for implantation of prosthetic joint components. The system may further include an articulating insert trial mounted on the guide assembly to determine preferred joint alignment and/or optimal positioning of the guide plate.

Abstract: Knee prostheses featuring components that more faithfully replicate the structure and function of the human knee joint in order to provide, among other benefits: greater flexion of the knee in a more natural way by promoting or at least accommodating internal tibial rotation in a controlled way, replication of the natural screw home mechanism, and controlled articulation of the tibia and femur respective to each other in a more natural way. In a preferred embodiment, such prostheses include an insert component disposed between a femoral component and a tibial component, the insert component preferably featuring among other things a reversely contoured posterolateral bearing surface that helps impart internal rotation to the tibia as the knee flexes.

Abstract: A tibial insert includes a base and a post extending from the base along a longitudinal axis. The post has a medial surface, a lateral surface, and a height along the longitudinal axis. The medial surface has a medial section, and the lateral surface has a lateral section oriented substantially parallel to the medial section. The medial section and the lateral section each have a width in a substantially anterior-posterior direction that is sufficient to enable varus/valgus constraint over a flexion/extension range from extension to about 90 to 120 degrees of flexion when the tibial insert is mated with a femoral component.

Abstract: The invention relates to a prosthesis for implantation into a long bone during joint arthroplasty, particularly Total Shoulder Arthoplasty and Total Hip Arthroplasty, and a method for use of the implant.

Abstract: A system and method for placing a prosthetic acetabular cup within an acetabulum are disclosed. The system may comprise an acetabular cup with an eccentric socket. The acetabular cup may be substantially hemispherical with a cup rim and a portion of the cup rim removed defining a relief. The cup may accommodate a concentric liner in an eccentric position. Screw apertures may be present on the periphery of the cup and the screw trajectories may converge toward the dome of the cup. The cup is attached to a tool which is offset relative to the cup because of the substantially eccentric socket. The relief, when the cup is secured to the acetabulum, is positioned substantially anterior and the socket is positioned more posterior to provide a more natural center of rotation of a femoral head within the socket. The first relief reduces impingement of the acetabular cup on soft tissue.

Abstract: A method for placing a prosthetic acetabular cup within an acetabulum comprises implanting an acetabular cup with an eccentric socket. The acetabular cup may be substantially hemispherical with a cup rim and a portion of the cup rim removed defining a relief. The cup may accommodate a concentric liner in an eccentric position. Screw apertures may be present on the periphery of the cup and the screw trajectories may converge toward the dome of the cup. The cup is attached to a tool which is offset relative to the cup because of the substantially eccentric socket. The relief, when the cup is secured to the acetabulum, is positioned substantially anterior and the socket is positioned more posterior to provide a more natural center of rotation of a femoral head within the socket. The first relief reduces impingement of the acetabular cup on soft tissue.

Abstract: Implants and methods are presented for surgically repairing a hip joint with a proximal femoral prosthesis that comprises femoral head component and a femoral stem component. The femoral stem component comprises a neck portion, a flange portion, a transitional body region and an elongated stem. The femur is prepared for implantation of the femoral hip prosthesis by resecting the proximal femur and reaming a symmetric intramedullary cavity in the femur. The femoral hip prosthesis is then inserted the on the resected femur and in the intramedullary cavity. The femoral hip prosthesis elastically deforms when loaded during use to apply dynamic compressive loads and displacement to the calcar region of the resected proximal femur.

Abstract: A knee prosthesis including femoral and tibial implants, a tibial insert and a cam post assembly. The femoral implant is secured to a femur and has a cam feature and condyles. The tibial implant is secured to a tibia. The tibial insert has articulating surfaces that match the contours of the condyles of the femoral implant, and may have a medial boss that aligns with the tibial implant to provide rotation about a medially displaced rotation axis. A cam post is secured to the tibial implant and passes through a channel of the tibial insert. A motion limiting structure provides limits to motion between the tibial insert and the tibial baseplate. The cam post assembly interacts with the femoral implant cam feature and allows more anatomically correct rollback and femoral external rotation during knee flexion, and varus/valgus support to the femur.

Abstract: A method for performing an acetabular arthroplasty in an acetabulum of an ilium may include locating an iliac canal of the ilium. The iliac canal extends from the surface of the acetabulum generally toward a portion of the iliac ridge. An impacting step impacts a non-rotating bone removal tool aligned along the iliac canal such that the non-rotating bone removal tool removes bone within the iliac canal and forms a bone void. Another step secures a fixation implant within the canal void. An acetabular implant is installed within the acetabulum over the fixation implant.

Abstract: An acetabular prosthetic device for implantation in an iliac canal and acetabulum of an ilium comprises a stem and an acetabular component. The stem may be configured to be implanted in the iliac canal. The acetabular component may be configured to be implanted in the acetabulum and fixed to the stem. The acetabular component may further comprise a connection portion to adjustably connect the acetabular component to the stem such that the acetabular component is configured to be oriented in a plurality of orientations before being fixed to the stem.

Abstract: A knee prosthesis including a femoral implant, a tibial implant, a tibial insert and a cam post. The femoral implant is secured to a femur and has a gap for receiving a natural PCL. The tibial implant is secured to a tibia. The tibial insert comprises a medial cavity with a rotational axis. The tibial insert has articulating surfaces that match the contours of the condyles of the femoral implant and a notch for retaining the natural PCL. The tibial insert has a medial boss that aligns with the medial cavity allowing it to rotate about the rotational axis. A post is secured to the tibial implant and enters a hole of the tibial insert providing anterior and posterior stops for the rotation of the tibial insert about the rotational axis.

Abstract: Certain embodiments generally provide an improved tibial base member comprising keel portions that allow one or both cruciate ligaments to be preserved. Other embodiments provide improved lateral and/or medial inserts having a mesial lip that helps relieve and/or prevent impingement between the femoral component and the tibial eminence. Other embodiments provide improved femoral components having various chamfers to provide additional clearance with respect to the tibial eminence and posterior cruciate ligament without decreasing bone coverage.

Abstract: Knee prosthesis instrumentation including an insertion tool and a removal tool. The insertion tool may include an offset to provide clearance from a femoral component of the knee prosthesis. The removal tool may be wedge shaped to at least partially encircle a post of the knee prosthesis for removal. A mallet may be used with the instruments to provide additional force for prosthesis insertion or removal. A slide hammer may be incorporated into the instruments themselves.

Abstract: A trial system for an implantable joint replacement includes a guide assembly having a baseplate and a guide plate, the guide plate translatable relative to the base plate along a straight path while directly connected to the baseplate. A first adjustment mechanism may selectively control the translational juxtaposition of the guide plate relative to the baseplate. The guide plate may further be rotatable relative to the baseplate around a rotation axis. A second adjustment mechanism may selectively control the rotational juxtaposition of the guide plate relative to the baseplate, and can lock the plates together. The rotation axis may be medially offset from the center of the guide assembly. The guide plate provides in situ positionable cutting guidance for implantation of prosthetic joint components. The system may further include an articulating insert trial mounted on the guide assembly to determine preferred joint alignment and/or optimal positioning of the guide plate.

Abstract: A trial system for an implantable joint replacement includes a guide assembly having a baseplate and a guide plate, the guide plate rotatable relative to the base plate about a rotation axis extending through the guide plate and the baseplate while directly connected to the baseplate. An adjustment mechanism is actuable to selectively control the rotational juxtaposition of the guide plate relative to the baseplate. The rotation axis may be medially offset from the center of the guide assembly. A single instrument may be used to rotate the guide plate relative to the base plate and lock the plates in the selected juxtaposition. The guide plate provides in situ positionable cutting guidance for implantation of prosthetic joint components. The system may further include an articulating insert trial mounted on the guide assembly to determine preferred joint alignment and/or optimal positioning of the guide plate.

Abstract: A knee prosthesis including a femoral implant, a tibial implant, a tibial insert and a cam post. The femoral implant is secured to a femur and has a cam feature and condyles. The tibial implant is secured to a tibia. The tibial insert comprises a medial cavity with a rotational axis. The tibial insert has articulating surfaces that match the contours of the condyles of the femoral implant. The tibial insert has a medial boss that aligns with the medial cavity allowing it to rotate about the rotational axis. A cam post is secured to the tibial implant and passes through a channel of the tibial insert providing anterior and posterior stops for the rotation of the tibial insert about the rotational axis. The cam post interacts with the femoral implant cam feature and, with the tibial insert, allows more anatomically correct rollback and femoral external rotation during knee flexion.