Knee joint prosthesis

• US 7,445,639 B2
• Filed: 02/21/2006
• Issued: 11/04/2008
• Est. Priority Date: 02/23/2001
• Status: Expired due to Term

• Current Assignee: Biomet Manufacturing, LLC (Zimmer Biomet Holdings, Inc.)
• Original Assignee: Biomet Manufacturing, LLC (Zimmer Biomet Holdings, Inc.)
• Inventors: Hoeppner, Jacy C, Metzger, Robert G
• Primary Examiner(s): Isabella; David J.
• Assistant Examiner(s): Blanco; Javier G
• Application Number:
  US11/358,926
• Publication Number:
  US 20060142867A1
• Time in Patent Office: 987 Days
• Field of Search: 623/20.11, 623/20.14, 623/20.15, 623/20.21, 623 2028- 2036, 623/23.18, 623/23.26, 623/23.34, 623/23.35, 623 2344- 2346, 623/21.11, 623/21.12, 623/21.15, 623/21.18, 623/21.19, 623/22.11, 623/22.4, 623/22.42, 623/23.39, 623/23.47
• US Class Current: 623/20.15
• CPC Class Codes: A61F 2/30721 Accessories
• CPC Class Codes: A61F 2/38 for elbows or knees
• CPC Class Codes: A61F 2002/30133 kidney-shaped or bean-shaped
• CPC Class Codes: A61F 2002/30143 hexagonal
• CPC Class Codes: A61F 2002/30154 square
• CPC Class Codes: A61F 2002/30329 Connections or couplings between prosthetic parts, e.g. between modular parts; Connecting elements
• CPC Class Codes: A61F 2002/30336 Stepped cones, i.e. having discrete diameter changes
• CPC Class Codes: A61F 2002/30339 Double cones, i.e. connecting element having two conical connections, one at each of its opposite ends
• CPC Class Codes: A61F 2002/30354 Cylindrically-shaped protrusion and recess, e.g. cylinder of circular basis
• CPC Class Codes: A61F 2002/30357 Stepped cylinders, i.e. having discrete diameter changes
• CPC Class Codes: A61F 2002/30405 made by screwing complementary threads machined on the parts themselves
• CPC Class Codes: A61F 2002/30433 using additional screws, bolts, dowels, rivets or washers e.g. connecting screws
• CPC Class Codes: A61F 2002/30476 locked by an additional locking mechanism
• CPC Class Codes: A61F 2002/30538 for adjusting angular orientation
• CPC Class Codes: A61F 2002/30574 with an integral complete or partial collar or flange
• CPC Class Codes: A61F 2002/30594 slotted, e.g. radial or meridian slot ending in a polar aperture, non-polar slots, horizontal or arcuate slots
• CPC Class Codes: A61F 2002/30604 modular
• CPC Class Codes: A61F 2002/30616 Sets comprising a plurality of prosthetic parts of different sizes or orientations
• CPC Class Codes: A61F 2002/30774 internally-threaded
• CPC Class Codes: A61F 2002/3079 Stepped or enlarged apertures, e.g. having discrete diameter changes
• CPC Class Codes: A61F 2002/30797 : internally-threaded
• CPC Class Codes: A61F 2002/30878 : with non-sharp protrusions, for instance contacting the bone for anchoring, e.g. keels, pegs, pins, posts, shanks, stems, struts
• CPC Class Codes: A61F 2002/4638 : Tools for performing screwing, e.g. nut or screwdrivers, or particular adaptations therefor
• CPC Class Codes: A61F 2220/0025 : Connections or couplings between prosthetic parts, e.g. between modular parts; Connecting elements
• CPC Class Codes: A61F 2220/0033 : made by longitudinally pushing a protrusion into a complementary-shaped recess, e.g. held by friction fit
• CPC Class Codes: A61F 2220/0041 : using additional screws, bolts, dowels or rivets, e.g. connecting screws
• CPC Class Codes: A61F 2230/0015 : Kidney-shaped, e.g. bean-shaped
• CPC Class Codes: A61F 2230/0017 : Angular shapes
• CPC Class Codes: A61F 2230/0021 : square
• CPC Class Codes: A61F 2250/0006 : for adjusting angular orientation

Abstract

A modular component for a knee joint prosthesis is disclosed. The modular component includes a tray, a stem and an adapter assembly. The tray includes a support surface and downwardly extending extension having a generally circular shape. The stem includes a main body portion and an upwardly extending extension. The adapter assembly connects the tray and the stem. The adapter assembly includes a first generally cylindrical cavity receiving the downwardly extending extension of the tray and a second generally cylindrical cavity receiving the upwardly extension of the stem.

Claims

1. A modular tibial component for a knee joint prosthesis, the modular tibial component comprising:

a tibial tray having a support surface and a first extension;

a tibial stem having a main body portion and a second extension;

an adapter body extending along a longitudinal axis and connecting the tray and the stem and establishing a nonzero offset between the first extension of the tray and the second extension of the stem, the adapter body defining a first cavity to receive the first extension of the tray and a second cavity to receive the second extension of the stem, the adapter body further including a sidewall defining an opening communicating with a passage, the passage transversely intersecting the longitudinal axis and the first and second cavities; and

a locking mechanism for coupling the tray to the stem, the locking mechanism including a first locking element passing through the opening into the passage and coupling the first and second extensions.

2. The modular tibial component for a knee joint prosthesis of claim 1, wherein the first cavity is generally cylindrical and includes a first central axis and the second cavity is generally cylindrical and includes a second central axis, the first and second central axes being parallel to one another and spaced apart.

3. The modular tibial component for a knee joint prosthesis of claim 1, wherein the locking element includes an upper surface having an internally threaded aperture, the aperture threadably receiving fastener extending through the first extension of the tray.

4. The modular tibial component for a knee joint prosthesis of claim 1, wherein the locking element includes an open end and a bottom surface having a slot for receiving a portion of the stem as the locking element is inserted through the opening.

5. The modular tibial component for a knee joint prosthesis of claim 4, wherein the portion of the stem received in the slot is an insert threadably coupled with the stem.

6. The modular tibial component for a knee joint prosthesis of claim 1, wherein the stem includes a reduced diameter portion, the locking element engaging the reduced diameter portion.

7. The modular tibial component for a knee joint prosthesis of claim 1, wherein the locking element includes an open end and a bottom surface having a slot intersecting the open end and wherein the stem includes a head received in the open end and having a diameter greater than a width of the slot.

8. The modular tibial component of claim 1,

wherein the locking mechanism includes a second locking element;

wherein the second locking element is operable to pass through at least a portion of one of the first cavity, the second cavity, or combinations thereof to engage the first locking element.

9. The modular tibial component of claim 8, wherein the first locking element is operable to interact with the second locking element to draw the tibial tray toward the second locking element.

10. The modular tibial component of claim 9, wherein the first locking element includes a threaded aperture and the second locking element includes an externally threaded portion threadably engaging the threaded aperture.

11. A modular component for implanting in a portion of an anatomy, comprising:

a tray having a support surface and a first extension;

a stem having a body portion and a second extension;

an adapter extending along a longitudinal axis and operable to connect the tray and the stem, the adapter defining a first cavity to receive the first extension and a second cavity to receive the second extension, the second cavity transversely offset relative to the first cavity by a nonzero offset, the adapter having an outer wall defining a passage transversely intersecting the longitudinal axis and the second cavity;

a stem insert having a head, central portion of reduced width relative to the head, and an end portion coupled to the second extension; and

a locking member received in the passage and lockingly engaging the central portion of the stem insert.

12. The modular component of claim 11, wherein the end portion of the stem insert threadably engages a threaded recess of the second extension.

13. The modular component of claim 11, wherein the locking member includes a slot engaging the central portion of the insert.