Knee arthroplasty prosthesis and method

• US 20030158606A1
• Filed: 02/19/2003
• Published: 08/21/2003
• Est. Priority Date: 02/20/2002
• Status: Abandoned Application

• Current Assignee: Zimmer Incorporated (Zimmer Biomet Holdings, Inc.)
• Original Assignee: Zimmer Incorporated (Zimmer Biomet Holdings, Inc.)
• Inventors: Van Zile, Richard R., Tria, Alfred J. Jr., Coon, Thomas M., Smucker, Donald M.
• Application Number:
  US10/370,154
• Publication Number:
  US 20030158606A1
• Time in Patent Office: Days
• US Class Current: 623/20.15
• CPC Class Codes: A61F 2/30744 End caps, e.g. for closing an endoprosthetic cavity
• CPC Class Codes: A61F 2/38 for elbows or knees
• CPC Class Codes: A61F 2/3859 Femoral components
• CPC Class Codes: A61F 2/389 Tibial components A61F2/3868 takes precedence
• CPC Class Codes: A61F 2/4637 for connecting or disconnecting two parts of a prosthesis
• CPC Class Codes: A61F 2002/30331 made by longitudinally pushing a protrusion into a complementarily-shaped recess, e.g. held by friction fit
• CPC Class Codes: A61F 2002/30332 Conically- or frustoconically-shaped protrusion and recess
• 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 2002/30387 Dovetail connection
• 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 2002/30492 using a locking pin
• CPC Class Codes: A61F 2002/30515 using a locking wedge or block
• 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 2002/30708 Means for distinguishing between left-sided and right-sided devices, Sets comprising both left-sided and right-sided prosthetic parts
• 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 2002/30822 Circumferential grooves
• 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 2002/30884 : Fins or wings, e.g. longitudinal wings for preventing rotation within the bone cavity
• CPC Class Codes: A61F 2002/30892 : parallel
• CPC Class Codes: A61F 2002/30975 : made of two halves
• CPC Class Codes: A61F 2002/4631 : the prosthesis being specially adapted for being cemented
• 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 2250/0084 : Means for distinguishing between left-sided and right-sided devices; Sets comprising both left-sided and right-sided prosthetic parts

Abstract

A knee arthroplasty prosthesis includes a femoral component having multiple pieces with engagement means provided for engaging various pieces of the femoral component to one another following their insertion in the incised area of the femur. A tibial component includes multiple pieces designed for assembly following positioning in the incision. The tibial component includes a Morse taper cavity on one piece of the tibial component and a Morse taper extension on another member of the component for receipt therein.

Claims

1. A femoral component for knee arthroplasty in a knee having a natural patella or a prosthetic patella comprising

(a) a first piece having a patellar femoral flange portion including an articulating surface for engagement by said patella, said first piece extending from an anterior end toward a posterior end and having one or more engagement surfaces defining one side of a joint;

(b) a second piece defining at least one condylar portion and having an articulating surface, said second piece extending from said posterior end toward said anterior end and having one or more abutment surfaces cooperating with said engagement surfaces to define said joint; and

(c) a fastener for securing said first piece and said second piece together.

2. The femoral component of claim 1 further including a third piece defining a second condylar portion extending from said posterior end toward said anterior end and having at least one abutment surface cooperating with said engagement surface to define a second joint and further including a second fastener for securing said third piece to said first piece.

3. The femoral component of claim 1 wherein said second piece includes first and second condylar portions and at least one laterally extending cross member supporting said first condylar portion to said second condylar portion.

4. The femoral component of claim 3 wherein said cross member is located adjacent said posterior end.

5. The femoral component of claim 3 wherein there is provided a first cross member located adjacent said posterior end and a second cross member located adjacent said abutment surfaces.

6. The femoral component of claim 3 wherein said at least one laterally extending cross member is located adjacent said abutment surfaces.

7. The femoral component of claim 6 wherein said first piece includes a central surface extending laterally and first and second side engagement surfaces extending from said central surface angularly away from each other in a direction toward said anterior end, and wherein said second piece cross member has (i) a medial surface spaced from said condylar portion articulating surface, (ii) an opposed bone engaging surface, and (iii) a leading surface facing said first piece and extending between said medial surface and said bone engaging surface and wherein said first piece includes a ledge extending anteriorly from said central surface, said ledge engaged to said cross member medial surface.

8. The femoral component of claim 7 further including a first piece extension extending superiorly from said ledge and a second piece extension extending superiorly from said cross member, said first piece extension and said second piece extension having a mating tongue and groove configuration for joining together.

9. The femoral component of claim 3 wherein said first piece includes a central surface extending laterally and first and second side engagement surfaces extending from said central surface angularly away from each other in a direction toward said anterior end.

10. The femoral component of claim 1 wherein the articulating surface of said first piece in the area of said joint and the articulating surface of said second piece in the area of said joint cooperate to form a recess.

11. The femoral component of claim 1 wherein said joint is in an area of low stress from sliding engagement by the patella.

12. The femoral component of claim 1 wherein said second piece has (i) two condylar portions, each having an articulating surface, and (ii) a connecting section having an articulating surface extending smoothly from both of said condylar portions articulating surfaces to said one or more abutment surfaces.

13. The femoral component of claim 12 wherein said one or more engagement surfaces and said one or more abutment surfaces each define a series of intermeshing valleys and projections with apertures extending through or into projections of each of said first piece and said second piece and an engagement pin or screw extending into apertures of both said first piece and said second piece.

14. The femoral component of claim 12 wherein one of said one or more abutment surfaces of said first piece extends transversely of said first piece and superiorly from its said articulating surface throughout only a portion of the thickness of said first piece and further including a wall extending anteriorly from said first piece one abutment surface and a first ledge spaced from said wall and cooperating therewith to define an insert slot and wherein one of said one or more abutment surfaces of said second piece extends transversely of said second piece and superiorly from its said articulating surface throughout only a portion of the thickness of said second piece and an insert ledge extending from said second piece one abutment surface and engaged in said insert slot.

15. The femoral component of claim 14 wherein one of said first ledge or said insert ledge is provided with a slot and the other of said first ledge or said insert ledge is provided with a tongue received in said slot.

16. The femoral component of claim 15 wherein said slot and said tongue are provided with mating reverse tapers.

17. The femoral component according to claim 16 wherein said insert ledge extends only partially into said slot leaving a transverse space between said insert ledge and said first piece and further including an elongated member extending into said space.

18. A femoral knee prosthesis component for use with a tibial component having an articulating surface comprising:

(a) a condylar piece having (i) a superior surface contoured to engage a prepared surface at the distal end of a femur, (ii) an opposing articulating surface contoured for sliding engagement with said tibial component articulating surface and extending from (I) a posterior end to (II) an abutment end;

(b) a second piece having (i) a superior surface contoured to engage a prepared surface at the distal end of a femur (ii) an opposing articulating surface contoured for sliding engagement by a natural of prosthetic patella and extending from (I) an anterior end (II) an engagement end contoured for mating engagement with said condylar piece abutment end; and

(c) engagement means for securing said condylar piece to said second piece.

19. The prosthesis of claim 18 wherein said condylar piece abutment end and said second piece engagement end are positioned to be located, following implantation, in an area of low stress from sliding engagement of said patella.

20. The prosthesis of claim 18 wherein said second piece comprises (a) a condylar portion and (b) a patellar flange portion.

21. The prosthesis of claim 18 wherein said engagement means includes (a) apertures in said condylar piece and said second piece, and (b) a fastening member extending into apertures of both said condylar piece and said second piece.

22. The prosthesis of claim 18 wherein said condylar piece includes first and second spaced apart condylar portions joined together by one or more cross members and said second piece is a patellar flange member.

23. The prosthesis of claim 22 wherein said one cross member is positioned adjacent said posterior end.

24. The prosthesis of claim 22 wherein said one cross member is positioned at said abutment end.

25. The prosthesis of claim 24 wherein said cross member has (i) a superior bone engaging surface, (ii) a medial surface spaced from said superior bone engaging surface, and (iii) a second piece engaging surface extending between said superior bone engaging surface and said medial surface.

26. The prosthesis of claim 25 wherein said second piece includes a laterally extending surface positioned between said second piece superior surface and said second piece articulating surface, said laterally extending. surface being engageable with said cross member.

27. The prosthesis of claim 18 wherein said engagement means includes a recess on one of said condylar piece or said second piece and a projection engageable in said recess on the other of said condylar piece or said second piece.

28. The prosthesis of claim 27 further including (i) apertures in said condylar piece and said second piece, at least one aperture in said projection and (ii) a fastening member extending into both an aperture of said condylar piece and an aperture of said second piece.

29. A tibial component for use in knee arthroplasty comprising

(a) a tibial base having (i) an inferior surface for engagement with a prepared surface at the proximal end of a tibia and (ii) a passageway extending through said base;

(b) a tibial stem extending distally from said base; and

(c) means for engaging said stem to said base.

30. The tibial component of claim 29 wherein said passageway in the area of said tibial stem has a wall surface portion defining a Morse taper and said tibial stem has a portion defining a Morse taper sized to be snugly engaged in said passageway Morse taper portion.

31. The tibial component of claim 30 wherein a threaded aperture is provided in said tibial stem proximal end portion and further including a screw extending through said tibial base passageway engaged to said threaded aperture.

32. The tibial component of claim 30 wherein said passageway Morse taper portion tapers outwardly in a distal direction.

33. The tibial component of claim 32 wherein a threaded aperture is provided in said tibial stem proximal end portion and further including a screw extending through said tibial base passageway engaged to said threaded aperture.

34. The tibial component of claim 32 wherein said tibial stem is provided with an outwardly facing annular groove spaced distally from said Morse taper portion.

35. The tibial component of claim 30 wherein said passageway Morse taper portion tapers inwardly in a distal direction.

36. The tibial component of claim 35 wherein a threaded aperture is provided in said tibial stem proximal end portion and further including a screw extending through said tibial base passageway engaged to said threaded aperture.

37. The tibial component of claim 35 wherein said tibial base passageway is enlarged proximally of said Morse taper portion to define a shoulder extending outwardly from said Morse taper portion and further including inwardly facing threads proximally of said shoulder.

38. The tibial component of claim 37 wherein said tibial stem has a flange portion proximally of said stem Morse taper portion and outwardly facing threads engaged to said inwardly facing threads.

39. The tibial component of claim 38 wherein said flange portion is spaced from said shoulder when said stem Morse taper portion is snugly engaged to said base Morse taper portion.

40. The tibial component of claim 29 further including alignment means on said tibial base alignment with alignment means on said tibial stem.

41. A tibial component for a knee prosthesis comprising

(a) a tibial base having an inferior surface for engaging prepared bone at the proximal end of the tibia, an extension extending distally from said inferior surface to a distal end, a passageway extending through said tibial base, including through said extension, the distal end of said passageway defining a Morse taper;

(b) a tibial stem extending from a proximal end to a distal end, said proximal end defining a Morse taper receivable in said passageway Morse taper.

42. The tibial component according to claim 41 wherein said tibial stem has a recess extending from said proximal end toward said distal end, said recess having threads or other retention means formed therein and further including an engagement member extending through said tibial base passageway and engaged to said threads or other retention means.

43. The tibial component of claim 41 wherein said passageway Morse taper portion tapers outwardly in a distal direction.

44. The tibial component of claim 43 wherein a threaded aperture is provided in said tibial stem proximal end portion and further including a screw extending through said tibial base passageway engaged to said threaded aperture.

45. The tibial component of claim 44 wherein said tibial stem is provided with an outwardly facing annular groove spaced distally from said Morse taper portion.

46. The tibial component of claim 41 wherein said passageway Morse taper portion tapers inwardly in a distal direction.

47. The tibial component of claim 46 wherein a threaded aperture is provided in said tibial stem proximal end portion and further including a screw extending through said tibial base passageway engaged to said threaded aperture.

48. The tibial component of claim 46 wherein said tibial base passageway is enlarged proximally of said Morse taper portion to define a shoulder extending outwardly from said Morse taper portion and further including inwardly facing threads proximally of said shoulder.

49. The tibial component of claim 48 wherein said tibial stem has a flange portion proximally of said stem Morse taper portion and outwardly facing threads engaged to said inwardly facing threads.

50. The tibial component of claim 49 wherein said flange portion is spaced from said shoulder when said stem Morse taper portion is snugly engaged to said base Morse taper portion.

51. The tibial component of claim 41 further including alignment means on said tibial base alignable with alignment means on said tibial stem.

52. A method of performing knee arthroplasty comprising the steps of

(a) providing a multi-piece femoral component, said femoral component including (i) a first piece extending from an anterior end to an engagement surface and having a patellar femoral flange portion including an articulating surface and an opposed superior bone engaging surface, (ii) a second piece defining at least one condylar portion extending from a posterior end to an abutment surface and having an inferior surface and an opposed superior bone engaging surface, and (iii) means for securing said first piece and said second piece together;

(b) preparing the distal end of a femur to receive said first piece and said second piece;

(c) positioning one of said first piece or said second piece on said prepared femur distal end;

(d) thereafter positioning the other of said first piece or said second piece on said prepared femur distal end with said engagement surface and said abutment surface in contact with one another and cooperating to define a joint; and

(e) securing said first piece and said second piece together.

53. The method of claim 52 wherein step (e) is performed simultaneously with step (d).

54. The method of claim 52 wherein step (e) is performed following step (d).

55. A method of performing knee arthroplasty comprising the steps of

(a) providing a multi-piece tibial component, said tibial component including (i) a tibial base having an inferior surface for engagement with a prepared surface at the proximal end of a tibia and a passageway extending through said base, (ii) a tibial stem extending distally from said base, and (iii) means for engaging said stem to said base;

(b) preparing the proximal end of a tibia including forming a cavity along the intramedullary canal of said tibia;

(c) positioning one of said tibial base or said tibial stem on said prepared tibia;

(d) thereafter positioning the other of said tibial base or said tibial stem on said prepared tibia; and

(e) securing said tibial base and said tibial stem together.

56. The method of claim 55 wherein said passageway includes a portion in the area of said inferior surface which tapers outwardly in a distal direction and said tibial stem includes a tapered extension shaped to snugly engage said tapered portion of said passageway including the steps of positioning said tibial stem in said prepared cavity and thereafter positioning said tibial base on said tibial stem with said tibial stem extension in said tapered position.

57. The method of claim 56 further including the step of supporting said tibial stem in said prepared cavity prior to positioning said tibial base thereon.

58. The method of claim 56 wherein said tibial stem has an annular groove distally of said tapered extension and further including the step of engaging said groove with a tool to support said tibial stem in said prepared cavity prior to positioning said tibial base thereon.

59. The method of claim 56 wherein said tibial stem tapered extension has a threaded cavity and further including the step of extending a screw through said passageway and engaging it in said threaded cavity.

60. The method of claim 55 wherein said passageway included a portion which tapers inwardly in a distal direction and said stem includes a tapered extension shaped to snugly engage the tapered portion of said passageway and including the steps of positioning said tibial base on said prepared tibia proximal end and thereafter positioning said tibial stem through said passageway, into said prepared cavity and into engagement with said tibial base.

61. The method of claim 60 wherein said tibial base has inwardly facing threads and said tibial stem has outwardly facing threads proximally of said tapered extension and further including the step of engaging said outwardly facing threads to said inwardly facing threads.

62. The method of claim 61 wherein said tibial component further includes an insert engageable with said base, said insert having a passageway and said tibial stem extension having a threaded cavity and further extending a screw through said insert passageway and engaging it in said extension threaded cavity.