Hip prosthesis

Claim 2

An acetabular implant for implantation in an acetabular cavity of a patient comprising a generally semi-spherical acetabular cup including a fixation hole positioned at a location spaced from an edge of the cup so that the hole can be substantially aligned with the pectineal line of the patient when the cup is implanted in the cavity, a portion of an exterior surface of the cup and at least partially spaced from the edge of the cup being porous to promote bone ingrowth upon implantation of the cup, the portion of the exterior cup surface extending over at least a part of the hole, a remainder of the exterior cup surface spaced from the hole and contiguous with at least a portion of the edge of the cup being substantially smooth to inhibit bone ingrowth, and an elongated anchor insertable into the pelvis for mechanically fixing the cup to the pelvis, the anchor including means for engaging the cup and applying a force to the cup in the direction of the anchor to thereby firmly seat the cup in the cavity.

Claim 3

The implant according to claim 1 wherein the portion of the exterior surface is defined by a plurality of indented surface sections, and wherein the surface sections are porous.

Claim 4

An implant according to claim 1 wherein the anchor is constructed of a resorbable material.

Claim 5

An acetabular implant for implantation in an acetabular cavity of a patient comprising a generally semi-spherical acetabular cup including a fixation hole positioned at a location spaced from an edge of the cup so that the hole can be substantially aligned with the pectineal line of the patient when the cup is implanted in the cavity, a portion of an exterior surface of the cup being porous to promote bone ingrowth upon implantation of the cup, the portion of the exterior cup surface extending over at least a part of the hole, a remainder of the exterior surface of the cup spaced from the hole being substantially smooth to inhibit bone ingrowth, an elongated anchor for insertion in the pelvis, the anchor including means for mechanically fixing the anchor to the pelvis so that a free end thereof communicates with the cavity, the hole being positioned on the cup so that it can be axially aligned with and placed over the protruding end of the anchor when the cup is placed into the acetabular cavity, and securing means extending through the hole and engaging the cup and the anchor for applying a force to the cup in the direction of the anchor to thereby firmly seat the cup in the cavity.

Claim 6

An acetabular implant for implantation in an acetabular cavity of a patient comprising a generally semi-spherical acetabular cup including a fixation hole positioned at a location spaced from an edge of the cup so that the hole can be substantially aligned with the pectineal line of the patient when the cup is implanted in the cavity, a portion of an exterior surface of the cup being porous to promote bone ingrowth upon implantation of the cup, the portion of the exterior cup surface extending over at least a part of the hole, a remainder of the exterior surface of the cup spaced from the hole being substantially smooth to inhibit bone ingrowth, an elongated anchor for insertion in the pelvis, the anchor including means for mechanically fixing the anchor to the pelvis so that a free end thereof communicates with the cavity, the hole being positioned on the cup so that it can be axially aligned with and placed over the protruding end of the anchor when the cup is placed into the acetabular cavity, and securing means extending through the hole and engaging the cup and the anchor for applying a force to the cup in the direction of the anchor to thereby firmly seat the cup in the cavity.

Claim 7

An implant according to claim 4 wherein the securing means comprises a screw member threadably engaging the anchor.

Claim 8

An implant according to claim 5 wherein the screw member has a head, and wherein the hole includes a recess dimensioned to receive the head.

Claim 9

An implant according to claim 4 wherein the mechanically fixing means includes an exterior thread adapted to threadably engage the pelvis and located at the ends of the anchor opposite the free end.

Claim 10

An implant according to claim 4 including an insert having a generally semi-spherical configuration adapted to be disposed in contact with an interior surface of the cup, the liner defining generally spherical acetabular socket.

Claim 11

An implant according to claim 8 including means preventing relative movement between the cup and the insert when the latter is disposed within the former.

Claim 12

An implant according to claim 9 wherein the insert extends over an arc greater than the arc of the cup so that a portion of the insert protrudes past the cup when disposed within the cup.

Claim 13

An implant according to claim 10 wherein the insert extends over an arc approximately 10° larger than the arc of the cup.

Claim 14

An acetabular implant comprising an elongated anchor having a first end disposed within and mechanically substantially immovably fixed to a portion of a pelvic bone of a patient and a free end extending in a generally downward direction into an acetabular cavity defined by the pelvis, the anchor being substantially aligned with the pectineal line of the pelvis; an acetabular cup disposed within the cavity and having a fixation hole spaced from an edge of the cup and aligned with the anchor, the free end of the anchor extending into the hole; a screw member disposed within the fixation hole, threadably engaging the anchor and demountably fixing the cup to the anchor, the cup having an exterior shape selected so that it generates a press-fit with the acetabular cavity, a portion of an exterior surface of the cup surrounding the hole extending over less than the entire exterior surface so that the portion is at least partially spaced from the cup edge, the portion being porous to facilitate bone ingrowth into such portion; a remainder of the exterior cup surface being spaced from the hole and substantially smooth to inhibit bone ingrowth; and a liner constructed of a material having a relatively low coefficient of friction disposed within the cup and defining a generally semi-spherically shaped acetabular socket engaging a ball member connected with the patient's femur.

Claim 15

An acetabular implant comprising an elongated anchor having a first end disposed within and mechanically substantially immovably fixed to a portion of a pelvic bone of a patient and a free end extending in a generally downward direction into an acetabular cavity defined by the pelvis, the anchor being substantially aligned with the pectineal line of the pelvis; an acetabular cup disposed within the cavity and having a fixation hole spaced from an edge of the cup and aligned with the anchor, the free end of the anchor extending into the hole; a screw member disposed within the fixation hole, threadably engaging the anchor and demountably fixing the cup to the anchor, the cup having an exterior shape selected so that it generates a press-fit with the acetabular cavity, a portion of an exterior surface of the cup surrounding the hole extending over less than the entire exterior surface so that the portion is at least partially spaced from the cup edge, the portion being porous to facilitate bone ingrowth into such portion; a remainder of the exterior cup surface being spaced from the hole and substantially smooth to inhibit bone ingrowth; and a liner constructed of a material having a relatively low coefficient of friction disposed within the cup and defining a generally semi-spherically shaped acetabular socket engaging a ball member connected with the patient's femur.

Claim 16

A femoral implant adapted to be mechanically fixed to a femur with a pressfit between the implant and the femur comprising an intertrochanteric body adapted to be forced into an upwardly open intertrochanteric cavity previously formed proximate an upper end of the femur to correspond in shape to the shape of the body so as to establish intimate, pressfit contact between the body and the cavity, the body defining generally opposite and spaced apart anterior and posterior sides and generally opposite, spaced apart lateral and medial sides, a spacing between the lateral and medial sides decreasing in a generally downward direction, the body further defining an interior load transferring surface which is contiguous with at least one side, disposed generally below said one side and angularly inclined relative to said one side so as to face generally downwardly and being adapted to intimately contact a correspondingly formed surface of the femur for the transmission of compressive forces between the body and the femur via the load transferring surface, at least the interior loading surface including a porous area for promoting bone ingrowth when in contact with living bone; a neck protruding from the body and oriented to extend in a generally upward and medial direction; and a ball attached to the neck and formed to be movably disposed within a generally semi-spherical acetabular socket.

Claim 17

A femoral implant adapted to be mechanically fixed to a femur with a pressfit between the implant and the femur comprising an intertrochanteric body adapted to be forced into an upwardly open intertrochanteric cavity previously formed proximate an upper end of the femur to correspond in shape to the shape of the body so as to establish intimate, pressfit contact between the body and the cavity, the body defining generally opposite and spaced apart anterior and posterior sides and generally opposite, spaced apart lateral and medial sides, a spacing between the lateral and medial sides decreasing in a generally downward direction, the body further defining an interior load transferring surface which is contiguous with at least one side, disposed generally below said one side and angularly inclined relative to said one side so as to face generally downwardly and being adapted to intimately contact a correspondingly formed surface of the femur for the transmission of compressive forces between the body and the femur via the load transferring surface, at least the interior loading surface including a porous area for promoting bone ingrowth when in contact with living bone; a neck protruding from the body and oriented to extend in a generally upward and medial direction; and a ball attached to the neck and formed to be movably disposed within a generally semi-spherical acetabular socket.

Claim 18

A femoral implant according to claim 13 wherein the interior loading surface is contiguous with at least one of the posterior and anterior sides of the body.

Claim 19

A femoral implant according to claim 14 wherein and interior loading surface is contiguous with both the anterior side and the posterior side of the body.

Claim 20

A femoral implant according to claim 13 including guide means connected with the body, depending generally downwardly thereof, and formed to extend into a medullary cavity of the femur for guiding the body into the intertrochanteric cavity during implantation of the implant in the femur.

Claim 21

A femoral implant according to claim 16 including means for detachably securing the guide means to the body.

Claim 22

A femoral implant according to claim 17 wherein the guide means is constructed of a biodegradable material.

Claim 23

A femoral implant according to claim 16 wherein the guide means comprises an elongated stem, and wherein the means for detachably securing comprises a threaded interconnection between the stem and the body.

Claim 24

A femoral implant according to claim 19 wherein the threaded interconnection is defined by a female threaded portion in the body and a male threaded portion on the stem.

Claim 25

A femoral implant according to claim 16 wherein the guide means comprises an elongated stem having a length substantially longer than the length of the body.

Claim 26

A femoral implant according to claim 21 wherein the stem has a smooth, non-porous surface to inhibit bone ingrowth.

Claim 27

A femoral implant according to claim 13 wherein the ball is separate of the neck, and means for immovably securing the ball to the neck.

Claim 28

A femoral implant according to claim 23 wherein the ball securing means comprises cooperating Morse tapers formed on the ball and on the neck.

Claim 29

A femoral implant according to claim 13 wherein the anterior and posterior sides each include a porous area for promoting bone ingrowth when in contact with living bone.

Claim 30

A femoral implant according to claim 25 wherein the medial side includes a porous area for promoting bone ingrowth when in contact with living bone.

Claim 31

A femoral implant according to claim 26 wherein the lateral side includes a porous area for promoting bone ingrowth when in contact with living bone.

Claim 32

A femoral implant according to claim 13 wherein the lateral side is smooth to prevent bone ingrowth when in contact with living bone.

Claim 33

A femoral implant according to claim 28 wherein the medial side is smooth to prevent bone ingrowth when in contact with living bone.

Claim 34

A femoral hip implant comprising an elongated stem disposed in a medullary cavity of a femur, the stem having a substantially smooth surface to inhibit bone ingrowth and extending upwardly towards an intertrochanteric cavity defined by walls of the femur and previously formed at an upper end of the femur; an intertrochanteric body integrally constructed with and disposed generally above the stem, tightly engaging walls defining the intertrochanteric cavity to thereby mechanically fix the body to the femur and having an anterior side and an opposite, spaced apart posterior side, a lateral side and an opposing, spaced apart medial side, the body further defining first and second spaced apart interior load transferring surfaces contiguous with the stem, the anterior side and the posterior side, respectively, and being angularly inclined relative to anterior and posterior sides, each interior load transferring surface facing generally downwardly and sloping generally downwardly in the medial direction at an angle of about 70° relative to longitudinal axis of the stem, at least the load transferring surface of the body being porous and in intimate contact with bone tissue to promote bone ingrowth into the porous sides and the surfaces; a neck extending upwardly from the body in a generally medial direction; and a ball immovably attached to the neck and movably disposed within a generally spherical acetabular socket on the patient's pelvis.

Claim 35

A femoral hip implant comprising an elongated stem disposed in a medullary cavity of a femur, the stem having a substantially smooth surface to inhibit bone ingrowth and extending upwardly towards an intertrochanteric cavity defined by walls of the femur and previously formed at an upper end of the femur; an intertrochanteric body integrally constructed with and disposed generally above the stem, tightly engaging walls defining the intertrochanteric cavity to thereby mechanically fix the body to the femur and having an anterior side and an opposite, spaced apart posterior side, a lateral side and an opposing, spaced apart medial side, the body further defining first and second spaced apart interior load transferring surfaces contiguous with the stem, the anterior side and the posterior side, respectively, and being angularly inclined relative to anterior and posterior sides, each interior load transferring surface facing generally downwardly and sloping generally downwardly in the medial direction at an angle of about 70° relative to longitudinal axis of the stem, at least the load transferring surface of the body being porous and in intimate contact with bone tissue to promote bone ingrowth into the porous sides and the surfaces; a neck extending upwardly from the body in a generally medial direction; and a ball immovably attached to the neck and movably disposed within a generally spherical acetabular socket on the patient's pelvis.

Claim 36

A femoral implant for implantation in a femur comprising an intertrochanteric body adapted to be forced into an upwardly open intertrochanteric cavity previously formed proximate an upper end of the femur for receiving and tightly engaging the body so as to mechanically fix the body and therewith the implant to the femur, the body defining generally opposite and spaced apart anterior and posterior sides and generally opposite, spaced apart lateral and medial sides, an interior load transferring surface formed to be in contact with a corresponding surface of the cavity and which is contiguous with and angularly inclined relative to at least one side for the transmission of compressive forces between the body and the femur via the load transferring surface and the corresponding cavity surface, the body also including a porous area for promoting bone ingrowth when in contact with living bone, a stem attached to the body for extending into the medullary cavity and constructed of a biodegradable material, and a ball attached to the body and formed to be movably disposed within a generally semi-spherical acetabular socket.

Claim 37

A femoral implant for implantation in a femur comprising an intertrochanteric body adapted to be forced into an upwardly open intertrochanteric cavity previously formed proximate an upper end of the femur for receiving and tightly engaging the body so as to mechanically fix the body and therewith the implant to the femur, the body defining generally opposite and spaced apart anterior and posterior sides and generally opposite, spaced apart lateral and medial sides, an interior load transferring surface formed to be in contact with a corresponding surface of the cavity and which is contiguous with and angularly inclined relative to at least one side for the transmission of compressive forces between the body and the femur via the load transferring surface and the corresponding cavity surface, the body also including a porous area for promoting bone ingrowth when in contact with living bone, a stem attached to the body for extending into the medullary cavity and constructed of a biodegradable material, and a ball attached to the body and formed to be movably disposed within a generally semi-spherical acetabular socket.

Claim 38

A prosthetic hip for a patient comprising an acetabular cavity including a generally semispherical acetabular cup including a fixation hole spaced from an edge of the cup and positioned so that the hole can be substantially aligned with the pectineal line of the patient when the cup is implanted in the cavity, a portion of an exterior surface of the cup being porous to promote bone ingrowth upon implantation of the cup, the portion of the exterior cup surface extending over at least a part of the hole, a remainder of the exterior surface of the cup which is spaced from the hole being substantially smooth, and an elongated anchor insertable through the hole into the pelvis for mechanically fixing the cup to the pelvis, the anchor including means for engaging the cup and applying a force to the cup in the direction of the anchor to thereby firmly seat the cup in the cavity, and a femoral implant for implantation in a femur including an intertrochanteric body adapted to be forced into an upwardly open intertrochanteric cavity previously formed proximate an upper end of the femur to correspond in shape and size to the body so as to tightly engage the body and thereby mechanically fix the body to the femur, the body defining generally opposite and spaced apart anterior and posterior sides and generally opposite, spaced apart lateral and medial sides, a spacing between the lateral and medial sides decreasing in a generally downward direction, the body further defining an interior load transferring surface which is contiguous with at least one side, angularly inclined relative to said at least one side and generally downwardly facing for the transmission of compressive forces between the interior load transferring surface and a correspondingly shaped and positioned surface of the femur, the sides and the interior loading surface including porous areas for promoting bone ingrowth when in contact with living bone; a neck protruding from the body and oriented to extend in a generally upward and medial direction; and a ball attached to the neck and formed to be movably disposed within and cooperate with the acetabular implant.

Claim 39

A prosthetic hip for a patient comprising an acetabular cavity including a generally semispherical acetabular cup including a fixation hole spaced from an edge of the cup and positioned so that the hole can be substantially aligned with the pectineal line of the patient when the cup is implanted in the cavity, a portion of an exterior surface of the cup being porous to promote bone ingrowth upon implantation of the cup, the portion of the exterior cup surface extending over at least a part of the hole, a remainder of the exterior surface of the cup which is spaced from the hole being substantially smooth, and an elongated anchor insertable through the hole into the pelvis for mechanically fixing the cup to the pelvis, the anchor including means for engaging the cup and applying a force to the cup in the direction of the anchor to thereby firmly seat the cup in the cavity, and a femoral implant for implantation in a femur including an intertrochanteric body adapted to be forced into an upwardly open intertrochanteric cavity previously formed proximate an upper end of the femur to correspond in shape and size to the body so as to tightly engage the body and thereby mechanically fix the body to the femur, the body defining generally opposite and spaced apart anterior and posterior sides and generally opposite, spaced apart lateral and medial sides, a spacing between the lateral and medial sides decreasing in a generally downward direction, the body further defining an interior load transferring surface which is contiguous with at least one side, angularly inclined relative to said at least one side and generally downwardly facing for the transmission of compressive forces between the interior load transferring surface and a correspondingly shaped and positioned surface of the femur, the sides and the interior loading surface including porous areas for promoting bone ingrowth when in contact with living bone; a neck protruding from the body and oriented to extend in a generally upward and medial direction; and a ball attached to the neck and formed to be movably disposed within and cooperate with the acetabular implant.

Claim 40

A procedure for the implantation of a femoral hip joint component comprising the steps of: (a) resecting the head and neck of a femur to expose the interior thereof; (b) shaping an intertrochanteric, upwardly open cavity in the femur which has substantially parallel, spaced apart anterior and interior sides, a lateral side and a spaced apart medial side and load transmitting, generally upwardly facing interior load transferring ledges at a lower end of the anterior and posterior sides which are angularly inclined relative thereto; (c) providing a femoral implant which includes an intertrochanteric body having anterior and posterior sides, a lateral side and a medial side, and interior load transferring surfaces for the transmission of compressive forces to the ledges which face generally downwardly and are contiguous with a lower end of the anterior and posterior sides, the sides and the interior load transferring surfaces being shaped complementary to the corresponding sides and the ledges of the cavity and dimensioned to tightly engage the intertrochanteric cavity, the femoral implant further including a downwardly extending, elongated stem; (d) inserting the femoral implant into the femur by extending the stem into the medullary cavity and pressing the intertrochanteric body into the intertrochanteric cavity to tightly seat the former in the latter whereby a compressive force applied to the femur and the implant is transmitted via the interengaged ledges and surfaces; (e) promoting the ingrowth of bone at an area where the body contacts the bone tissue; (f) inhibiting the ingrowth of bone over substantially full length of the stem; and (g) providing a ball on the femoral implant for placement into an acetabular socket.

Claim 41

A procedure for the implantation of a femoral hip joint component comprising the steps of: (a) resecting the head and neck of a femur to expose the interior thereof; (b) shaping an intertrochanteric, upwardly open cavity in the femur which has substantially parallel, spaced apart anterior and interior sides, a lateral side and a spaced apart medial side and load transmitting, generally upwardly facing interior load transferring ledges at a lower end of the anterior and posterior sides which are angularly inclined relative thereto; (c) providing a femoral implant which includes an intertrochanteric body having anterior and posterior sides, a lateral side and a medial side, and interior load transferring surfaces for the transmission of compressive forces to the ledges which face generally downwardly and are contiguous with a lower end of the anterior and posterior sides, the sides and the interior load transferring surfaces being shaped complementary to the corresponding sides and the ledges of the cavity and dimensioned to tightly engage the intertrochanteric cavity, the femoral implant further including a downwardly extending, elongated stem; (d) inserting the femoral implant into the femur by extending the stem into the medullary cavity and pressing the intertrochanteric body into the intertrochanteric cavity to tightly seat the former in the latter whereby a compressive force applied to the femur and the implant is transmitted via the interengaged ledges and surfaces; (e) promoting the ingrowth of bone at an area where the body contacts the bone tissue; (f) inhibiting the ingrowth of bone over substantially full length of the stem; and (g) providing a ball on the femoral implant for placement into an acetabular socket.

Claim 42

A procedure according to claim 33 wherein the step of providing a ball comprises the step of providing a femoral implant having a neck; providing a separate ball; and securing the ball to the neck.

Claim 43

A procedure according to claim 34 wherein the neck defines a tapered shaft; the ball defines a correspondingly tapered bore; and wherein the step of securing comprises the step of frictionally engaging the ball with the neck to thereby immovably secure the two to each other.

Claim 44

A procedure according to claim 33 wherein the step of forming the intertrochanteric cavity includes the step of forming the ledges so that they slope downwardly in the medial direction at an angle of about 70° relative to the axis of the femur, whereby a force transmitted through the hip joint is transmitted from the surfaces to the ledges substantially perpendicularly thereto, whereby substantially only compressive stresses therebetween are generated.

Claim 45

A procedure according to claim 36 wherein the step of resection includes the step of resecting the head and neck of the femur to form an exterior load transferring face thereon which is contiguous with the intertrochanteric cavity, is oriented generally upwardly and is inclined at an angle of about 70° to the axis of the femur substantially parallel to the angular inclination of the ledge, and including the steps of contacting the face with a correspondingly shaped and oriented exterior load transferring surface on the implant, and promoting bone ingrowth over the exterior load transferring surface.

Claim 46

A procedure according to claim 37 wherein the step of promoting bone ingrowth comprises the step of forming porous surface on the implant over areas where bone ingrowth is desired.

Claim 47

A procedure according to claim 33 wherein the step of inhibiting comprises the step of providing the stem with a smooth surface finish.

Claim 48

A procedure according to claim 33 wherein the step of inhibiting comprises the step of permitting the stem to resorb.