Implant with resorbable stem

Claim 2

An anchor for a permanent implant for a bone joint comprising an elongated member for insertion into a bone cavity for fixing the implant relative to the bone, the member being constructed substantially entirely of a biodegradable material so that the member can resorb after a period of time, the member having an exterior surface shaped to tightly engage the cavity and to be substantially immovably disposed within the cavity after being placed therein, and means for securing the member to the permanent implant.

Claim 3

An anchor according to claim 1 wherein the securing means comprises a threaded hole in the member.

Claim 4

An anchor according to claim 1 wherein the exterior surface defines a male thread.

Claim 5

An anchor according to claim 1 wherein the exterior surface is substantially smooth.

Claim 6

An anchor according to claim 1 wherein the exterior surface is shaped to tightly fit into a canal defined by a natural bone.

Claim 7

An anchor according to claim 2 wherein the threaded hole is engageable with an externally threaded screw engaging a surface of the permanent implant.

Claim 8

An anchor according to claim 1 wherein the biodegradable material is selected from the group consisting of polyesters of glycolic acid, polyesters of lactic acid, polyamides of α-amino acids, unmodified polymers, modified polymers, calcium hydroxyapatite, tricalcium phosphate or polylactic acid.

Claim 9

An anchor according to claim 15 wherein the permanent bone implant is selected from an alloy of cobalt-chromium or titanium.

Claim 10

An anchor according to claim 15 wherein the implant is part of a prosthetic hip.

Claim 11

An anchor according to claim 15 wherein the implant is part of a prosthetic knee.

Claim 12

An anchor according to claim 15 wherein the implant is part of a prosthetic shoulder.

Claim 13

An anchor according to claim 1 wherein the elongated member is a threaded bolt and the securing means include a screw engaging the permanent implant threading into the bolt.

Claim 14

An anchor according to claim 1 wherein the elongated member is a stem having an exterior surface that is substantially smooth and wherein the securing means comprises a threaded hole in the stem and a screw engaging the permanent implant for threading into the hole in the stem.

Claim 15

A procedure for the implantation of a prosthetic implant comprising the steps of: a. providing a functional implant component adapted to remain in permanent contact with the bone; b. forming a portion of the component in contact with the bone so that bony ingrowth can attach directly thereto; c. opening a cavity in the bone; d. placing the functional component against the bone; e. inserting an anchor substantially completely constructed of a resorbable material into the cavity so that the anchor is substantially immovably disposed within the cavity; f. fixedly securing the component to the anchor so that the component is in contact with bone surrounding the cavity; g. growing bone proximate the cavity into the portion of the component to thereby permanently fix the component to the bone; and h. substantially completely resorbing the anchor after the completion of the promoting step so that natural tissue can grow back into the cavity.

Claim 16

A procedure for the implantation of a prosthetic implant comprising the steps of: a. providing a functional implant component adapted to remain in permanent contact with the bone; b. forming a portion of the component in contact with the bone so that bony ingrowth can attach directly thereto; c. opening a cavity in the bone; d. placing the functional component against the bone; e. inserting an anchor substantially completely constructed of a resorbable material into the cavity so that the anchor is substantially immovably disposed within the cavity; f. fixedly securing the component to the anchor so that the component is in contact with bone surrounding the cavity; g. growing bone proximate the cavity into the portion of the component to thereby permanently fix the component to the bone; and h. substantially completely resorbing the anchor after the completion of the promoting step so that natural tissue can grow back into the cavity.

Claim 17

A prosthetic implant for a bone joint comprising a component defining an operative portion of the joint, the component having an interface facing generally away from the joint and adapted to be placed into intimate contact with a natural bone to which the component is to be fixed, at least part of the interface including means promoting bony ingrowth when the interface is in intimate contact with the natural bone; an anchor connected to the component adapted to be inserted in a cavity in the bone for orienting and immovably fixing the component to the bone immediately upon implantation, the anchor being constructed of a biodegradable material so that it resorbs after a period of time and thereby vacates the cavity to permit natural bone to grow back into the cavity.

Claim 18

A prosthetic implant for a bone joint comprising a component defining an operative portion of the joint, the component having an interface facing generally away from the joint and adapted to be placed into intimate contact with a natural bone to which the component is to be fixed, at least part of the interface including means promoting bony ingrowth when the interface is in intimate contact with the natural bone; an anchor connected to the component adapted to be inserted in a cavity in the bone for orienting and immovably fixing the component to the bone immediately upon implantation, the anchor being constructed of a biodegradable material so that it resorbs after a period of time and thereby vacates the cavity to permit natural bone to grow back into the cavity.

Claim 19

An implant according to claim 15 including means for removably securing the anchor to the component.

Claim 20

An implant according to claim 15 wherein at least part of the cavity is a natural bone canal, and wherein the anchor has a smooth exterior surface.

Claim 21

An implant according to claim 15 wherein the cavity is a hole drilled in the bone, and wherein the anchor has an exterior surface defining a male thread adapted to threadably engage the hole in the bone.

Claim 22

An implant according to claim 15 wherein the component comprises a joint socket, wherein the anchor comprises a male threaded member adapted to threadably engage the cavity, and including means for securing the socket to the member.

Claim 23

An implant according to claim 19 including a plurality of threaded members for securing the socket to the bone.

Claim 24

An implant according to claim 15 wherein the component comprises a member having a convex exterior configuration adapted to cooperate with a concave joint member.

Claim 25

An implant according to claim 21 wherein the convex joint member comprises a ball joint member.

Claim 26

An implant according to claim 22 wherein the component further includes a body connected with the ball and defining the interface.

Claim 27

An implant according to claim 23 wherein the body and the ball are detachable secured to each other.

Claim 28

An implant according to claim 22 wherein a portion of the ball which faces the concave member has a generally spherical configuration, and wherein a portion of the ball which faces away from the concave member defines the interface.

Claim 29

An implant according to claim 25 wherein the interface includes a planar surface adapted to be placed into direct contact with a corresponding planar surface formed on the natural bone to which the implant is to be attached.

Claim 30

A procedure according to claim 14 wherein the step of opening a cavity comprises the step of broaching an existing canal in the bone, and wherein the step of inserting an anchor includes the step of forming a press-fit between the anchor and the cavity to thereby substantially immovably fix the anchor and thereby the functional implant to the bone.

Claim 31

A procedure according to claim 14 wherein the step of opening a cavity comprises the step of drilling a hole in the bone.

Claim 32

A procedure according to claim 28 wherein the step of inserting an anchor comprises the step of threadably engaging the anchor with the hole in the bone.

Claim 33

A procedure according to claim 14 wherein the step of forming comprises the step of constructing the functional implant component so that it has a surface which permits bony ingrowth into the component.

Claim 34

A procedure according to claim 14 wherein the step of resorbing includes the step of predetermining the length of time required for the anchor to substantially completely resorb.

Claim 35

A procedure for replacing a diseased natural joint component on a bone with a prosthetic joint component comprising the steps of: removing the diseased joint component and forming a load transference surface on the bone relatively proximate the diseased joint, providing the prosthetic joint component with an interface adapted to be placed into intimate contact with the load transference surface on the bone and forming at least a portion of the interface to promote bony ingrowth; bringing the interface of the prosthetic join component into intimate contact with the load transference surface on the bone, forming a cavity in the bone which communicates with the prosthetic component when the latter is in contact with the load transference surface, substantially immovably positioning an anchor in the cavity, substantially immovably attaching the prosthetic joint component to the anchor to retain the interface in contact with the load transference surface and to thereby promote bony ingrowth in to the portion of the interface while enabling use of the joint, and permitting the anchor to resorb after bony ingrowth into the portion of the prosthetic component interface has immovably fixed the prosthetic component directly to the bone; whereby load transference from the component to the bone takes place in the vicinity of the joint and is prevented from taking place in the cavity at locations relatively remote from the joint.

Claim 36

A procedure for replacing a diseased natural joint component on a bone with a prosthetic joint component comprising the steps of: removing the diseased joint component and forming a load transference surface on the bone relatively proximate the diseased joint, providing the prosthetic joint component with an interface adapted to be placed into intimate contact with the load transference surface on the bone and forming at least a portion of the interface to promote bony ingrowth; bringing the interface of the prosthetic join component into intimate contact with the load transference surface on the bone, forming a cavity in the bone which communicates with the prosthetic component when the latter is in contact with the load transference surface, substantially immovably positioning an anchor in the cavity, substantially immovably attaching the prosthetic joint component to the anchor to retain the interface in contact with the load transference surface and to thereby promote bony ingrowth in to the portion of the interface while enabling use of the joint, and permitting the anchor to resorb after bony ingrowth into the portion of the prosthetic component interface has immovably fixed the prosthetic component directly to the bone; whereby load transference from the component to the bone takes place in the vicinity of the joint and is prevented from taking place in the cavity at locations relatively remote from the joint.

Claim 37

A prosthetic implant for a bone joint comprising a component defining an operative portion of the joint, the component having a interface facing generally away from the joint and adapted to be placed into intimate contact with a natural bone to which the component is to be fixed, a part of the interface being adapted to directly connect to the natural bone when it is brought into intimate with the natural bone; an anchor connected to the component adapted to be inserted in a cavity in the bone for orienting and immovably fixing the component to the bone immediately upon implantation, the anchor being constructed substantially entirely of a biodegradable material so that it resorbs after a period of time and thereby vacates the cavity to permit natural bone to grow back into the cavity.

Claim 38

A prosthetic implant for a bone joint comprising a component defining an operative portion of the joint, the component having a interface facing generally away from the joint and adapted to be placed into intimate contact with a natural bone to which the component is to be fixed, a part of the interface being adapted to directly connect to the natural bone when it is brought into intimate with the natural bone; an anchor connected to the component adapted to be inserted in a cavity in the bone for orienting and immovably fixing the component to the bone immediately upon implantation, the anchor being constructed substantially entirely of a biodegradable material so that it resorbs after a period of time and thereby vacates the cavity to permit natural bone to grow back into the cavity.

Claim 39

Procedure for replacing a diseased, natural joint component of a bone with a prosthetic joint component comprising the steps of: removing the diseased joint component and forming a load transference surface on the bone relatively proximate the diseased join; providing a prosthetic joint component with an interface adapted to be placed into intimate contact with the load transference surface on the bone; adapting at least a portion of the interface so that it establishes a direct connection between such portion and the natural bone when it is brought into intimate contact with the natural bone; bringing the interface of the prosthetic joint component into intimate with the load transference surface on the bone; forming a cavity in the bone which communicates with the prosthetic component when the latter is in contact with the load transference surface; substantially immovably positioning an anchor in the cavity; substantially immovably attaching the prosthetic joint component to the anchor to retain the interface in contact with the load transference surface and to thereby promote the establishment of a direct connection between the portion of the interface and the load transference surface while enabling use of the joint; and permitting the anchor to resorb after the direct connection between the portion of the prosthetic component interface and the load transference surface has immovably fixed the prosthetic component directly to the bone; whereby load transference from the component to the bone takes place in the vicinity of the joint and is prevented from taking place in the cavity at locations relatively remote from the joint.

Claim 40

Procedure for replacing a diseased, natural joint component of a bone with a prosthetic joint component comprising the steps of: removing the diseased joint component and forming a load transference surface on the bone relatively proximate the diseased join; providing a prosthetic joint component with an interface adapted to be placed into intimate contact with the load transference surface on the bone; adapting at least a portion of the interface so that it establishes a direct connection between such portion and the natural bone when it is brought into intimate contact with the natural bone; bringing the interface of the prosthetic joint component into intimate with the load transference surface on the bone; forming a cavity in the bone which communicates with the prosthetic component when the latter is in contact with the load transference surface; substantially immovably positioning an anchor in the cavity; substantially immovably attaching the prosthetic joint component to the anchor to retain the interface in contact with the load transference surface and to thereby promote the establishment of a direct connection between the portion of the interface and the load transference surface while enabling use of the joint; and permitting the anchor to resorb after the direct connection between the portion of the prosthetic component interface and the load transference surface has immovably fixed the prosthetic component directly to the bone; whereby load transference from the component to the bone takes place in the vicinity of the joint and is prevented from taking place in the cavity at locations relatively remote from the joint.