A system and method for quantitatively assessing a press fit value (and provide a mechanism to evaluate optimal quantitative values) of any implant/bone interface regardless the variables involved including bone site preparation, material properties of bone and implant, implant geometry and coefficient of friction of the implant-bone interface without requiring a visual positional assessment of a depth of insertion. The following description is presented to enable one of ordinary skill in the art to make and use the invention and is provided in the context of a patent application and its requirements.

A hip implant is provided that includes a metal acetabular cup to be inserted into an acetabulum of the pelvis, a femoral head and neck portion with a polymer femoral head molded onto a metal formal head base that is attached to a metal femoral neck rod configured to be inserted into the neck of a femur, and a metal main body shaft configured to be inserted into a femoral shaft region of the femur and secured by bone screws. The head base may have stabilizing features, such as dimples and peripheral mounds, over which the femoral head is molded. The main body shaft also has diagonal hole located at the center line of the neck of the femur to receive the femoral neck rod at an adjustable angle. The femoral head interfaces with the acetabular cup as a smooth plastic-to-metal spherical-surface joint.

There is provided an acetabular cup liner for a total hip replacement (THR) prosthesis comprising an inner surface with a hemispherical portion having a radius of curvature. The hemispherical portion is disposed about a centerline and it intersects a hemisphere plane perpendicular to the centerline so that the intersection of the hemispherical portion and the plane define a circle having a radius equal to the radius of curvature. The liner further comprises a capture portion continuous with the hemispherical portion that has the same radius of curvature as the hemispherical portion and connects with the hemispherical portion at the hemispherical plane along a first arc of the circle on the plane, and extends a first distance out of the plane. The liner further comprises an insertion portion continuous with the hemispherical portion. The insertion region is connected with the hemispherical portion along a second arc of the circle on the plane. The distance from the centerline to the insertion portion is greater than the radius. The cup liner constrains the femoral ball portion of the THR prosthesis. The femoral ball portion is engaged with the liner by orienting the ball at an angle so that the shoulder portion of the ball aligns with the insertion portion, pressing the ball into the liner, and orienting the ball away from the angle.

The application discloses an artificial acetabular cup and a manufacturing method thereof. The artificial acetabular cup has an annular base and a dome extending from the annular base. At least a part of the inner layer of the dome is a solid layer, at least a part of the outer layer of the dome is a porous structure layer, and the thickness of the inner layer is less than that of the porous structure layer. The artificial acetabular cup of the present application has lower production cost and better performance.

A system and method for quantitatively assessing a press fit value (and provide a mechanism to evaluate optimal quantitative values) of any implant/bone interface regardless the variables involved including bone site preparation, material properties of bone and implant, implant geometry and coefficient of friction of the implant-bone interface without requiring a visual positional assessment of a depth of insertion. The following description is presented to enable one of ordinary skill in the art to make and use the invention and is provided in the context of a patent application and its requirements.

There is provided an acetabular cup liner for a total hip replacement (THR) prosthesis comprising an inner surface with a hemispherical portion having a radius of curvature. The hemispherical portion is disposed about a centerline and it intersects a hemisphere plane perpendicular to the centerline so that the intersection of the hemispherical portion and the plane define a circle having a radius equal to the radius of curvature. The liner further comprises a capture portion continuous with the hemispherical portion that has the same radius of curvature as the hemispherical portion and connects with the hemispherical portion at the hemispherical plane along a first arc of the circle on the plane, and extends a first distance out of the plane. The liner further comprises an insertion portion continuous with the hemispherical portion. The insertion region is connected with the hemispherical portion along a second arc of the circle on the plane. The distance from the centerline to the insertion portion is greater than the radius. The cup liner constrains the femoral ball portion of the THR prosthesis. The femoral ball portion is engaged with the liner by orienting the ball at an angle so that the shoulder portion of the ball aligns with the insertion portion, pressing the ball into the liner, and orienting the ball away from the angle.

An acetabular cup assembly for use with liners is described. The acetabular cup assembly includes a cup and a liner. The cup has an outer surface, a generally concave inner surface and a top face. The inner surface includes a cylindrical band having a plurality of inward-facing recessed scallops, a tapered wall adjacent to the band, and an inner spherical surface adjacent the tapered wall. The inner spherical surface has a substantially uniform radius of curvature. A single groove interrupts the spherical surface. The liner has a substantially convex outer surface and includes a rim and a plurality of outward-projecting scallops adjacent the rim. The scallops of the liner are configured to engage the scallops of the cup when the liner is seated in the cup. Related methods of use are also provided.

An acetabular cup assembly for use with liners is described. The acetabular cup assembly includes a cup and a liner. The cup has an outer surface, a generally concave inner surface and a top face. The inner surface includes a cylindrical band having a plurality of inward-facing recessed scallops, a tapered wall adjacent to the band, and an inner spherical surface adjacent the tapered wall. The inner spherical surface has a substantially uniform radius of curvature. A single groove interrupts the spherical surface. The liner has a substantially convex outer surface and includes a rim and a plurality of outward-projecting scallops adjacent the rim. The scallops of the liner are configured to engage the scallops of the cup when the liner is seated in the cup. Related methods of use are also provided.

There is provided an acetabular cup liner for a total hip replacement (THR) prosthesis comprising an inner surface with a hemispherical portion having a radius of curvature. The hemispherical portion is disposed about a centerline and it intersects a hemisphere plane perpendicular to the centerline so that the intersection of the hemispherical portion and the plane define a circle having a radius equal to the radius of curvature. The liner further comprises a capture portion continuous with the hemispherical portion that has the same radius of curvature as the hemispherical portion and connects with the hemispherical portion at the hemispherical plane along a first arc of the circle on the plane, and extends a first distance out of the plane. The liner further comprises an insertion portion continuous with the hemispherical portion. The insertion region is connected with the hemispherical portion along a second arc of the circle on the plane. The distance from the centerline to the insertion portion is greater than the radius. The cup liner constrains the femoral ball portion of the THR prosthesis. The femoral ball portion is engaged with the liner by orienting the ball at an angle so that the shoulder portion of the ball aligns with the insertion portion, pressing the ball into the liner, and orienting the ball away from the angle.

Multi-hooded enarthrodial joint implant has a ceramic articulating cup including a ceramic head-receiving cup having an articular surface upon which a head of a joint can articulate, and which, in general, has a margin generally about a hemisphere more or less and at least two hoods that are marginally extended continuations of superior one-half or so of cup containment of a sufficient magnitude to reduce an overall dimension of socket outlet to less than a hemisphere, which can embrace and contain the head. The head is made of ceramic and has a truncated generally circular cross section, a truncated surface with a feature for attachment of the stem, and an opposing articular surface for articulation against the articular surface of the ceramic head-receiving cup. As an ensemble, the cup is combined with the head, typically with a stem, for a total joint implant.