Zimmer Gmbh

Bristol-myers Squibb Compnay

Roy D Crowninshield

Jack E Parr

H Ravindranath Shetty

Thirumalai N Devanathan

Roy Y Hori

Walter H Ottersberg

Thomas Wade Fallin

Stephen H Hoag

Leslie N Gilbertson

Perry A Geremakis

Howard C Price

Arden R Zolman

Carl H Jacobs

Douglas H Wentz

Helen Chu

Dale A Degroff

Abner K Wang

A prosthetic hip stem for use in a prosthetic hip joint. The hip stem generally includes a core having a stem portion and a neck portion, a polymer matrix layer substantially covering the stem portion of the core, and a porous metal layer substantially covering the polymer matrix layer. The polymer matrix layer connects the core and the porous metal layer, and may be injection molded therebetween. The neck portion of the hip stem has a relatively thin or slender profile which allows for an increased degree of articulating movement of the hip stem with respect to the acetabular component of a prosthetic hip joint. The neck portion of the hip stem additionally includes a version indicator element, such as a bump or a protrusion, which may be tactilely felt by a surgeon to aid the surgeon in positioning the hip stem during a minimally invasive total hip arthroplasty procedure, for example, where direct visualization of the hip stem by the surgeon may not be possible. Additionally, the core of the hip stem includes grooves, ridges, flats, dimples or other features to enhance the mechanical interconnection between the core and the polymer matrix layer.

Fully porous prosthetic hip stem

An implant stem 10 and distal centralizer 20. Implant stem 10 has a plurality of longitudinal channels 14 formed around its periphery adjacent its distal end 12. Channels 14 converge radially toward the apex of the stem distal end 12. Channels extend only partially into the body of implant stem 10 to provide sufficient material to maintain the structural integrity of the distal end of the implant. Centralizer 20 includes a plurality of radially extending blades 22. The proximal end of each blade 22 is shaped to extend upwardly for securely mating with implant stem 10. The complimentary cruciate configuration of channels 14 and blades 22 allows centralizer 20 to be securely attached to implant stem 10.

Intramedullary implant stem and centralizer

An orthopaedic implant device is formed from, or defined by, a combination of different materials. These devices include a body metal component and a porous metal surface layer for intimate contact with bone and a polymer in the form of a casing that includes adhesive characteristics for attachment to the body metal component and the porous metal layer. The preferred polymer casing is polyaryletherketone.

Orthopaedic implant device

A method of surface hardening titanium orthopedic implant devices, and a titanium orthopedic implant device prepared by the disclosed method. An orthopedic implant device made of pure titanium or a titanium alloy, such as Ti-6Al-4V (ELI) is exposed to molecular nitrogen gas at a process temperature and for a process time duration sufficient to enhance surface hardness and wear resistance properties, without the formation of a measurable TiN layer that tends to increase surface roughness and diminish wear resistance properties. The process temperature is in the range of 750.degree. F. to 1300.degree. F., preferably about 1100.degree. F. and the process time duration at the preferred process temperature is approximately 8 hours. The hardened surface of the titanium implant occurs primarily due to solid solution hardening of the titanium with nitrogen by dissolution.

Method of surface hardening orthopedic implant devices

Centering cap for a prosthetic hip stem

A bone implant includes a nonmetallic core and a metallic porous surface secured to the nonmetallic core. The nonmetallic core is designed to closely approximate the modulus of elasticity for bone and the metallic porous surface is intimately engaged with bone to enhance bone growth into the metallic porous surface.

Bone implant

The present invention relates to a prosthetic interpositional device/coupler designed to be interposed between the neck and head of a femoral prosthesis. One example of a contemplated environment of use of the inventive interpositional device/coupler is in the situation where the prosthesis has a neck of one material and a head of another material. The inventive interpositional device/coupler may be made with an outer wall having a taper designed to match the taper of the head and with an inner wall having a taper designed to match the taper of the neck. These tapers may differ. Additionally, the inner and outer surfaces may have different surface textures from one another so as to make the respective walls compatible with the surface texture of the material of which the adjacent structure, head or neck, is made. Three embodiments of the inventive interpositional device/coupler are disclosed. The third embodiment is similar to the second embodiment except that the end wall is much thicker than the end wall in the second embodiment so that the device is greater in length than the second embodiment. The first embodiment does not include an end wall and may be shorter in length than either the second or third embodiment.

Prosthetic interpositional device/coupler

36 The present invention relates to a prosthetic interpositional device/coupler designed to be interposed between the neck and head of a femoral prosthesis. One example of a contemplated environment of use of the inventive interpositional device/coupler is in the situation where the prosthesis has a neck of one material and a head of another material. The inventive interpositional device/coupler may be made with an outer wall having a taper designed to match the taper of the head and with an inner wall having a taper designed to match the taper of the neck. These tapers may differ. Additionally, the inner and outer surfaces may have different surface textures from one another so as to make the respective walls compatible with the surface texture of the material of which the adjacent structure, head or neck, is made. Three embodiments of the inventive interpositional device/coupler are disclosed. The third embodiment is similar to the second embodiment except that the end wall is much thicker than the end wall in the second embodiment so that the device is greater in length than the second embodiment. The first embodiment does not include an end wall and may be shorter in length than either the second or third embodiment.

An orthopaedic prosthesis for implantation with a bone cement composition, the prosthesis including a polymer coating and a textured surface underneath at least a portion of the polymer coating. The textured surface, which is visible to the eye without magnification, beneath the polymer coating enhances or increases the surface shear and tensile strength of the prosthesis.

Prosthesis with enhanced surface finish

A nail device includes a plurality of segments fastened together by a resorbable bioadhesive such that the plurality of segments are gradually disassociated after the nail device is implanted into a bone. The disassociated segments exhibit less bending and torsional strength and stiffness than the fastened plurality of segments to reduce stress shielding for the bone.

Nail device

A femoral component for a hip prosthesis includes a stem with a porous surface or the like to enhance bone fixation. The porous surface is applied to the stem in a predetermined manner to accommodate stress lines for the stem and generate a curvilinear inferior boundary for the porous surface. A method of construction utilizes the stress lines to approximate a boundary for the porous surface.

Growing community of inventors

Warsaw, IN, United States of America

Roy D Crowninshield