Modular Hip Implant

• US 20090088865A1
• Filed: 04/18/2007
• Published: 04/02/2009
• Est. Priority Date: 04/19/2006
• Status: Active Grant

• Current Assignee: Peter Cremer Holding GmbH & Company KG (Handelsgesellschaft Peter Cremer mbH)
• Original Assignee: Peter Brehm GmbH
• Inventors: Brehm, Peter
• Granted Patent: US 9,005,302 B2
• Time in Patent Office: Days
• US Class Current: 623/22.210
• CPC Class Codes: A61B 17/86 Pins or screws or threaded wires; nuts therefor A61B17/72 take precedence
• CPC Class Codes: A61F 2/30744 End caps, e.g. for closing an endoprosthetic cavity
• CPC Class Codes: A61F 2/34 Acetabular cups
• CPC Class Codes: A61F 2/4603 for insertion or extraction of endoprosthetic joints or of accessories thereof
• CPC Class Codes: A61F 2/4637 for connecting or disconnecting two parts of a prosthesis
• CPC Class Codes: A61F 2002/30143 hexagonal
• CPC Class Codes: A61F 2002/30327 differing in diameter
• 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 2002/30405 made by screwing complementary threads machined on the parts themselves
• CPC Class Codes: A61F 2002/30426 Bayonet coupling
• CPC Class Codes: A61F 2002/30433 using additional screws, bolts, dowels, rivets or washers e.g. connecting screws
• CPC Class Codes: A61F 2002/30449 the adhesive being cement
• CPC Class Codes: A61F 2002/30487 Circumferential cooperating grooves and beads on cooperating lateral surfaces of a mainly longitudinal connection
• CPC Class Codes: A61F 2002/305 Snap connection
• CPC Class Codes: A61F 2002/30538 for adjusting angular orientation
• CPC Class Codes: A61F 2002/3054 about a connection axis or implantation axis for selecting any one of a plurality of radial orientations between two modular parts, e.g. Morse taper connections, at discrete positions, angular positions or continuous positions
• CPC Class Codes: A61F 2002/30576 with extending fixation tabs
• CPC Class Codes: A61F 2002/30578 having apertures, e.g. for receiving fixation screws
• 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 2002/30787 : inclined obliquely with respect to each other
• CPC Class Codes: A61F 2002/3401 : with radial apertures, e.g. radial bores for receiving fixation screws
• CPC Class Codes: A61F 2002/3403 : Polar aperture
• CPC Class Codes: A61F 2002/343 : partial, i.e. not extending along the entire equatorial circumference
• CPC Class Codes: A61F 2002/3432 : having apertures for receiving fixation screws
• CPC Class Codes: A61F 2002/3441 : the outer shell having an outer surface and an inner insert receiving cavity being angularly inclined with respect to the longitudinal axis of the outer surface
• CPC Class Codes: A61F 2002/3443 : with an anti-luxation elevated rim portion, e.g. on the inner shell
• CPC Class Codes: A61F 2002/3448 : Multiple cups made of three or more concentric shells fitted or nested into one another
• CPC Class Codes: A61F 2002/4629 : connected to the endoprosthesis or implant via a threaded connection
• 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 2220/0041 : using additional screws, bolts, dowels or rivets, e.g. connecting screws
• CPC Class Codes: A61F 2220/005 : using adhesives
• CPC Class Codes: A61F 2230/0017 : Angular shapes
• CPC Class Codes: A61F 2250/0006 : for adjusting angular orientation
• CPC Class Codes: A61F 2250/0039 : differing in diameter
• CPC Class Codes: A61F 2310/00023 : Titanium or titanium-based alloys, e.g. Ti-Ni alloys
• CPC Class Codes: A61F 2310/00029 : Cobalt-based alloys, e.g. Co-Cr alloys or Vitallium
• CPC Class Codes: A61F 2310/00203 : containing alumina or aluminium oxide
• CPC Class Codes: A61F 2310/00239 : containing zirconia or zirconium oxide ZrO2

Abstract

A modular hip implant is disclosed that includes a base member that is to be attached to a pelvic bone, and a cup for accommodating a hip joint prosthesis. The base member is provided with fasteners for mounting the base member on the pelvic bone as well as a concave accommodation portion for the cup. The cup has a convex outer shape which is complementary to the accommodation portion such that the radii of curvature determining the concave accommodation portion and the convex outer form essentially correspond to each other and the cup can be attached within the base member. The base member and/or the cup include adjustment means for adjusting the position of the cup relative to the base member. The invention allows the inclination and anteversion to be adjusted by arranging the cup in the base.

Claims

1-51. -51. (canceled)

52. A modular hip implant comprising a base member for attachment to a pelvic bone and comprising a cup for accommodating a hip joint prosthesis, wherein the base member is attachable to the pelvic bone and comprises an accommodation portion for the cup, wherein the cup has an outer shape complementary to the accommodation portion and the cup is attachable in the base member, wherein the base member and the cup comprise an adjusting mechanism for variable arrangement of the cup with respect to the base member, wherein the adjusting mechanism comprises guides formed in the base member and in the cup

53. A hip implant as claimed in claim 52, wherein the cup and the accommodation portion comprise a plurality of bores, wherein the bores have different diameters and wherein corresponding bores in the cup and in the accommodation portion are alignable with one another by moving the cup along the guides.

54. A hip implant as claimed in claim 52, wherein the outer side of the cup is formed such that the cup is fixable to the base member by means of a cement layer.

55. A hip implant as claimed in claim 52, wherein the base member comprises at least one bore, said at least one bore being adapted for accommodating an angularly stable screw for connecting the base member with the pelvic bone.

56. A hip implant as claimed in claim 52, wherein the guides comprise a groove and a projection.

57. A hip implant as claimed in claim 52, wherein the guides are arranged such that both an inclination and an anteversion are adjustable simultaneously, wherein the inclination and anteversion are adjustable in a defined manner by at least one of a rotation of the cup in the base member and an offset insertion of the cup into the base member in one or more latch positions.

58. A hip implant as claimed in claim 56, wherein the groove is formed at the inner surface of the accommodating portion and the projection is formed at an exterior of the cup, wherein the cup has a rim, and wherein the rim lies in a plane with whose normal a normal of a plane through the projection includes an angle α

being at least one of in a range from approximately 0°

to approximately 30°

, in a range from approximately 5°

to approximately 20° and

approximately equal to 17°

.

59. A hip implant as claimed in claim 56, wherein at least one of the projection and the groove is formed in an annularly circumferential manner.

60. A hip implant as claimed in claim 58, wherein the base member has an upper rim, which lies in a plane with whose normal a normal of a plane through the groove includes an angle β

being at least one of in a range from approximately 0°

to approximately 30°

, in a range from approximately 5°

to approximately 25°

, in a range from approximately 10°

to approximately 22° and

approximately equal to 20°

.

61. A modular hip implant comprising a base member for attachment to a pelvic bone, and comprising a cup for accommodating a hip joint prosthesis, wherein the base member is attachable to the pelvic bone and comprises an accommodation portion for the cup, wherein the cup has an outer shape complementary to the accommodation portion, wherein the cup comprises a first portion with an opening and a second portion, wherein the second portion is guidable through the opening of the first portion and attachable to the base member, and wherein the second portion is adapted to fix the first portion relative to the base member.

62. A hip implant as claimed in claim 61, wherein the base member and the second portion of the cup have fasteners corresponding to one another, the fasteners comprising an internal thread in the base member and an external thread corresponding thereto at the second portion of the cup.

63. A hip implant as claimed in claim 62, wherein the internal thread formed in the base member and the corresponding external thread at the second portion of the cup are formed as fine threads.

64. A hip implant as claimed in claim 62, wherein the base member comprises at least one bore, wherein an axis of the at least one bore is arranged substantially parallel to an axis of the internal thread in the base member.

65. A hip implant as claimed in claim 61, wherein the second portion of the cup is attachable to the base member by means of a cement layer.

66. A hip implant as claimed in claim 61, wherein the second portion of the cup is formed as a substantially spherical shell.

67. A hip implant as claimed in claim 61, wherein the first portion of the cup is fixable in a plurality of positions relative to the base member.

68. A hip implant as claimed in claim 67, wherein the first portion of the cup and the base member comprise a mechanism for pre-locking the first portion of the cup in a plurality of positions relative to the base member.

69. A hip implant as claimed in claim 68, wherein the mechanism for pre-locking the first portion of the cup comprises a bayonet lock.

70. A hip implant as claimed in claim 61, wherein the first portion of the cup and the base member comprise cooperating guides.

71. A hip implant as claimed in claim 61, wherein the base member comprises at least one bore, said at least one bore being adapted for accommodating an angularly stable screw for connecting the base member with the pelvic bone.

72. A modular hip implant comprising a base member, wherein the base member is attachable to the pelvic bone and comprises an accommodation portion having an internal shape complementary to a bearing insert of a hip joint prosthesis, wherein the accommodation portion comprises an opening that is closable by means of a closure element, wherein the closure element is attachable to the base member.

73. A modular hip implant as claimed in claim 72, wherein the base member and the closure element comprise fasteners corresponding to one another, wherein the fasteners comprise an internal thread in the base member and an external thread in the closure element that corresponds to the internal thread in the base member.

74. A modular hip implant as claimed in claim 72, wherein the closure element is adapted to supplement the accommodation portion to form a recess having an inner shape complementary to the bearing insert of the hip joint prosthesis.

75. A modular hip implant as claimed in claim 74, wherein the accommodation portion is formed as a spherical shell open on two sides, and wherein the closure element is formed as a spherical shell.

76. A modular hip implant as claimed in claim 72, wherein the base member comprises at least one bore, said at least one bore being adapted for accommodating an angularly stable screw for connecting the base member with the pelvic bone.

77. A tool for assembling a modular hip implant having a base member that is attachable to a pelvic bone, and a component that is adapted to be screwed to a thread provided in the base member, wherein at least one bore is formed in the base member, said bore comprising an axis which is substantially parallel to an axis of the thread provided in the base member, the tool comprising:

a guide rod that is insertable into the bore in the base member;

a guide sleeve displaceable along the guide rod; and

a screw-in instrument connected to the guide sleeve, wherein an axis of the screw-in instrument is arranged substantially parallel to the guide rod.

78. A tool as claimed in claim 77, wherein the guide rod comprises an external thread on an end thereof that is adapted to be screwed with an internal thread in the bore of the base member.

79. A tool as claimed in claim 77, wherein the screw-in instrument is pivotable around the guide rod.

80. A tool as claimed in claim 77, wherein the screw-in instrument comprises a mechanism for detachably attaching the component of the hip implant at the screw-in instrument.