Hip implant with porous body

• US 8,821,582 B1
• Filed: 08/23/2012
• Issued: 09/02/2014
• Est. Priority Date: 05/27/2003
• Status: Expired due to Fees

• Current Assignee: Four Mile Bay LLC
• Original Assignee: Four Mile Bay LLC
• Inventors: Lyren, Philip Scott
• Primary Examiner(s): Merene, Jan Christopher
• Assistant Examiner(s): COTRONEO, STEVEN J
• Application Number:
  US13/592,349
• Time in Patent Office: 740 Days
• Field of Search: 623/22.11, 623 2215- 2326, 623 2329- 2237, 623 2353- 2355, 606 62- 68
• US Class Current: 623/22.11
• CPC Class Codes: A61F 2/30767 Special external or bone-contacting surface, e.g. coating for improving bone ingrowth
• CPC Class Codes: A61F 2/36 Femoral heads ; Femoral endoprostheses
• CPC Class Codes: A61F 2/3609 Femoral heads or necks; Connections of endoprosthetic heads or necks to endoprosthetic femoral shafts A61F2/3601 takes precedence
• CPC Class Codes: A61F 2/3662 Femoral shafts
• CPC Class Codes: A61F 2/367 Proximal or metaphyseal parts of shafts trochanteric devices connected to said proximal parts A61F2/30739
• CPC Class Codes: A61F 2/3672 Intermediate parts of shafts
• CPC Class Codes: A61F 2002/2817 Bone stimulation by chemical reactions or by osteogenic or biological products for enhancing ossification, e.g. by bone morphogenetic or morphogenic proteins [BMP] or by transforming growth factors [TGF]
• CPC Class Codes: A61F 2002/30011 differing in porosity
• CPC Class Codes: A61F 2002/30112 Rounded shapes, e.g. with rounded corners
• CPC Class Codes: A61F 2002/30125 elliptical or oval
• CPC Class Codes: A61F 2002/30136 undulated or wavy, e.g. serpentine-shaped or zigzag-shaped
• CPC Class Codes: A61F 2002/30153 rectangular
• CPC Class Codes: A61F 2002/30154 square
• CPC Class Codes: A61F 2002/30156 triangular
• CPC Class Codes: A61F 2002/30158 trapezoidal
• CPC Class Codes: A61F 2002/30332 Conically- or frustoconically-shaped protrusion and recess
• CPC Class Codes: A61F 2002/30354 Cylindrically-shaped protrusion and recess, e.g. cylinder of circular basis
• CPC Class Codes: A61F 2002/30367 with additional means for preventing said rotation
• CPC Class Codes: A61F 2002/30403 Longitudinally-oriented cooperating ribs and grooves on mating lateral surfaces of a mainly longitudinal connection
• CPC Class Codes: A61F 2002/30604 modular
• CPC Class Codes: A61F 2002/30677 : Means for introducing or releasing pharmaceutical products, e.g. antibiotics, into the body
• CPC Class Codes: A61F 2002/30838 : Microstructures
• CPC Class Codes: A61F 2002/30906 : shot- sand- or grit-blasted
• CPC Class Codes: A61F 2002/3092 : having an open-celled or open-pored structure
• CPC Class Codes: A61F 2002/30925 : etched
• CPC Class Codes: A61F 2002/3093 : for promoting ingrowth of bone tissue
• CPC Class Codes: A61F 2002/30957 : using a positive or a negative model, e.g. moulds
• CPC Class Codes: A61F 2002/30968 : Sintering
• CPC Class Codes: A61F 2002/3611 : Heads or epiphyseal parts of femur
• CPC Class Codes: A61F 2002/3625 : Necks
• CPC Class Codes: A61F 2002/3631 : with an integral complete or partial peripheral collar or bearing shoulder at its base
• CPC Class Codes: A61F 2002/365 : Connections of heads to necks
• CPC Class Codes: A61F 2002/3652 : Connections of necks to shafts
• CPC Class Codes: A61F 2002/3694 : with longitudinal bores
• CPC Class Codes: A61F 2310/00023 : Titanium or titanium-based alloys, e.g. Ti-Ni alloys
• CPC Class Codes: A61F 2310/00796 : Coating or prosthesis-covering structure made of a phosphorus-containing compound, e.g. hydroxy(l)apatite

Abstract

A hip implant has a neck body that connects to a bone fixation body. The bone fixation body has a porous structure with an elongated shape. An internal cavity is formed in the bone fixation body and includes a substance to stimulate bone growth.

Claims

1. A method, comprising:

machining a neck body formed of solid metal to include a neck that receives a femoral ball and having a male protrusion that extends outwardly from the neck body;

fabricating, separately from the neck body, a bone fixation body with a porous metal structure that extends completely throughout the bone fixation body with the porous metal structure having a size and a shape that emulate a size and a shape of a porous structure of natural human bone; and

attaching, after the bone fixation body is separately fabricated from the neck body, the bone fixation body to the neck body to create a hip implant such that the male protrusion extends into and permanently attaches with the porous metal structure of the bone fixation body to create the hip implant before the hip implant is implanted, wherein the porous metal structure of the bone fixation body includes a trapezoidal shape in a horizontal cross-sectional view of the hip implant, and the male protrusion extends to a distal end of the hip implant.

2. The method of claim 1, wherein the bone fixation body and the neck body have an area with a polygonal shape in a horizontal cross-sectional view of the hip implant.

3. The method of claim 1, wherein the male protrusion of the neck body has a noncircular tapering shape and extends into the porous metal structure of the bone fixation body such that the porous metal structure surrounds an exterior surface of the male protrusion.

4. The method of claim 1, wherein the neck body engages the bone fixation body at an interface that has a trapezoidal shape in a horizontal cross-sectional view.

5. The method of claim 1, wherein the bone fixation body has an elongated tapering body with a bow.

6. The method of claim 1, wherein the bone fixation body is bonded to the neck body after being separately fabricated from the neck body and includes an agent to stimulate bone growth through a center of the bone fixation body in a horizontal cross-sectional view of the hip implant.

7. The method of claim 1, wherein the male protrusion of the neck body has one of a square shape and a rectangular shape and tapers while extending toward the distal end of the hip implant.

8. A method, comprising:

machining solid metal to form a neck body that includes a neck to receive a femoral ball and that includes a male protrusion that extends outwardly from the neck body;

making, separately from the neck body, a bone fixation body with a porous metal structure that extends throughout the bone fixation body with interconnected pores having a geometric structure with a shape and a size that emulate a shape and a size of natural human bone; and

connecting, after the bone fixation body is separately made from the neck body, the bone fixation body to the neck body to create a hip implant such that the male protrusion extends into the bone fixation body in order to permanently connect the neck body to the bone fixation body and create the hip implant, wherein the porous metal structure of the bone fixation body includes a trapezoidal shape in a horizontal cross-sectional view of the hip implant, and the male protrusion extends toward a distal end of the hip implant.

9. The method of claim 8, wherein the bone fixation body is fused to the neck body after the bone fixation body is made separately from the neck body.

10. The method of claim 8, wherein the male protrusion of the neck body is a core for the bone fixation body and has a polygonal and tapering shape that extends into the porous metal structure of the bone fixation body.

11. The method of claim 8, wherein the bone fixation body tapers and includes a bow shape.

12. The method of claim 8, wherein the bone fixation body includes a location with a polygonal shape in a horizontal cross-sectional view of the hip implant, and the porous metal structure fills a center of the polygonal shape in the horizontal cross-sectional view of the polygonal shape.

13. The method of claim 8, wherein the porous metal structure is uniform.

14. A method, comprising:

forming a neck body having a proximal end that connects with an acetabular component, having a distal end surface with a protrusion that extends outwardly therefrom, and being formed of solid metal;

forming a bone fixation body having an elongated tapering shape and having a porous metal structure with a size and a shape that emulate a size and a shape of a porous structure of natural human bone; and

engaging, after the neck body and the bone fixation body are separately formed, the bone fixation body to the neck body such that the porous metal structure permanently engages to the protrusion and the protrusion extends to a distal end of a hip implant and tapers and extends into an opening of the bone fixation body such that the porous metal structure surrounds and engages an exterior surface of the protrusion that extends into the bone fixation body, wherein the bone fixation body includes a trapezoidal shape in a horizontal cross-sectional view of the bone fixation body.

15. The method of claim 14, wherein the bone fixation body has one of a polygonal and noncircular closed shape in a horizontal cross-sectional view of the bone fixation body and is bonded to the neck body after being formed separately from the neck body.

16. The method of claim 14, wherein the bone fixation body includes a location having one of a polygonal shape and an oval shape in a horizontal cross-sectional view of the bone fixation body, and the porous metal structure extends through a center of the one of the polygonal shape and the oval shape in the horizontal cross-sectional view of the location.

17. The method of claim 14, wherein the bone fixation body is not a porous coating but is fabricated separately from the neck body and subsequently engaged to the neck body.

18. The method of claim 14, wherein the protrusion includes a polygonal shape in the horizontal cross-sectional view.

19. The method of claim 14, wherein a distal end surface of the neck body has a trapezoidal shape, a proximal end of the bone fixation body has the trapezoidal shape, and the solid metal of the trapezoidal shape of the neck body interfaces with the porous metal structure of the trapezoidal shape of the bone fixation body at an interface.

20. The method of claim 14, wherein the protrusion includes a cylindrical shape in a horizontal cross-sectional view.