Prosthesis component and method for its manufacture

• US 5,002,579 A
• Filed: 05/15/1987
• Issued: 03/26/1991
• Est. Priority Date: 05/16/1986
• Status: Expired due to Fees

• Current Assignee: Franz Copf, Savo Vesel, Ulrich Holz
• Original Assignee: Franz Copf, Savo Vesel, Ulrich Holz
• Inventors: Copf, Franz, Holz, Ulrich, Vesel, Savo
• Primary Examiner(s): Isabella, David J.
• Application Number:
  US07/049,989
• Time in Patent Office: 1,411 Days
• Field of Search: 623/16, 623/18, 623/20, 623/21, 623/22, 623/23
• US Class Current: 623/23.18
• CPC Class Codes: A61B 17/82 for bone cerclage apparatus for manipulating wires or straps A61B17/8861; wires, bands or straps other than cerclage A61B17/842
• CPC Class Codes: A61F 2/30767 Special external or bone-contacting surface, e.g. coating for improving bone ingrowth
• CPC Class Codes: A61F 2/3094 Designing or manufacturing processes
• CPC Class Codes: A61F 2/30942 for designing or making customized prostheses, e.g. using templates, CT or NMR scans, finite-element analysis or CAD-CAM techniques
• CPC Class Codes: A61F 2/3662 Femoral shafts
• CPC Class Codes: A61F 2/4644 Preparation of bone graft, bone plugs or bone dowels, e.g. grinding or milling bone material bone material A61F2/28; disintegrating or milling devices B02C
• CPC Class Codes: A61F 2002/2835 Bone graft implants for filling a bony defect or an endoprosthesis cavity, e.g. by synthetic material or biological material
• CPC Class Codes: A61F 2002/30224 cylindrical
• CPC Class Codes: A61F 2002/30327 differing in diameter
• CPC Class Codes: A61F 2002/30329 Connections or couplings between prosthetic parts, e.g. between modular parts; Connecting elements
• CPC Class Codes: A61F 2002/30462 retained or tied with a rope, string, thread, wire or cable
• CPC Class Codes: A61F 2002/30593 hollow
• CPC Class Codes: A61F 2002/30602 Shaft made of a bundle of anchoring rods or bristles, e.g. fasciculate shaft
• CPC Class Codes: A61F 2002/30879 Ribs
• CPC Class Codes: A61F 2002/30952 using CAD-CAM techniques or NC-techniques
• CPC Class Codes: A61F 2002/30957 using a positive or a negative model, e.g. moulds
• 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 2220/0025 Connections or couplings between prosthetic parts, e.g. between modular parts; Connecting elements
• CPC Class Codes: A61F 2220/0075 sutured, ligatured or stitched, retained or tied with a rope, string, thread, wire or cable
• CPC Class Codes: A61F 2230/0069 : cylindrical
• CPC Class Codes: A61F 2250/0039 : differing in diameter
• CPC Class Codes: A61F 2310/00029 : Cobalt-based alloys, e.g. Co-Cr alloys or Vitallium
• CPC Class Codes: A61F 2310/00407 : Coating made of titanium or of Ti-based alloys
• CPC Class Codes: B29L 2031/7532 : Artificial members, protheses

Abstract

An orthopedic prothesis component comprising a joint member and an anchoring member coupled thereto, said anchoring member including a plurality of elongated rod shaped anchoring posts and a support plate having an upper surface for carrying said joint member, and a lower surface configured to abut a resected surface of the bone and being connected to said anchoring posts, each of said anchoring posts containing a plurality of anchoring collars disposed at predetermined intervals along said posts, each of said collars having radial surfaces extending beyond the perimeter of said posts, whereby said collars serve to transfer loads imposed on the anchoring posts to spongiose material that is packed around said posts after the posts are positioned in the skeleton bone cavity.

Claims

1. An orthopedic prosthesis component (18) for implantation as a unit into a skeleton bone cavity comprising

(A) a joint member (29), and

(B) an anchoring member (20, 30) coupled to said joint member (28), said anchoring member only including:

(1) a plurality of elongated rod shaped anchoring posts (30) having opposite proximal and distal terminal ends and a substantially cross-sectional perimeter, and

(2) a support plate (20) having two opposing upper and lower surfaces,

(a) said upper surface adapted for carrying said joint member (28), and

(b) said lower surface configured to abut a resected surface of the bone and being connected to said anchoring posts (30) which extend into the prepared bone cavity in a series of curved paths oriented substantially along the trabecular structure of the bone,

each of said anchoring posts

containing a plurality of anchoring collars (32) disposed at predetermined intervals intervals along said posts, each of said collars having radial surfaces extending beyond the perimeter of said posts, whereby said collars serve to transfer loads imposed on the anchoring posts to spongiose material that is packed around said posts after the posts are positioned in the skeleton bone cavity.

2. A prosthesis component according to claim 1 wherein at least one anchoring post (88) has said distal end formed with a bend and connected to an adjacent anchoring post (86) at a location thereof which is remote from the distal end of said adjacent anchoring post (86).

3. A prosthesis component according to claim 1 wherein combination of said anchoring posts (102-108) define a tapering outer skeletal surface and wherein the distal ends of each of said anchoring posts of said combination being connected by a rounded end piece (11) that has a substantially smooth outer surface.

4. A prosthesis component according to claim 3 wherein said anchoring posts are divided into a first and second set, said anchoring posts of the first set having a core diameter of about 3.0-4.5 mm and said anchoring posts of the second set having a core diameter of about 1.5-3.0 mm, said anchoring collars of the first set having a diameter of about 0.8-1.5 mm larger than the anchoring posts of the first set and said anchoring collars of the second set having a diameter of about 0.6-2.0 mm larger than the anchoring posts of the second set, and the distance of the intervals between adjacent anchoring collars of the first and second sets being of about 3.0-6.0 mm and 2.0-4.0 mm, respectively.

5. A prosthesis component according to claim 3 wherein the support plate (20) is carried by two sets of anchoring posts, the anchoring posts of the first set being of a first length and a first cross-sectional area, while the anchoring posts of the second set are of a second length and a second cross-sectional area, the second length being smaller than the first length and the second cross-sectional area being smaller than the first cross-sectional area, and in that the anchoring posts of the first set are arranged at a first distance from each other, while the anchoring posts of the second set are arranged at a second distance from each other, the second distance being smaller than the first distance.

6. A prosthesis component according to claim 5 wherein transverse connecting posts (114-120) are formed with anchoring collars, said connecting posts (114-120) connecting the anchoring posts (102-108) of the first set, and in that the connecting posts (114-120) in turn support further anchoring posts (124) of said second length and said second cross-sectional area.

7. A prosthesis component according to claim 5 wherein the anchoring posts (124) of the second set substantially uniformly occupy a volume, the outer contour of which is defined by the anchoring posts (102-108) of the first set.