Containment system for constraining a prosthetic component

• US 7,335,231 B2
• Filed: 01/12/2004
• Issued: 02/26/2008
• Est. Priority Date: 01/25/2001
• Status: Expired due to Fees

• Current Assignee: Smith & Nephew Incorporated (Smith & Nephew PLC)
• Original Assignee: Smith & Nephew Incorporated (Smith & Nephew PLC)
• Inventors: McLean, Terry
• Primary Examiner(s): SNOW, BRUCE EDWARD
• Application Number:
  US10/755,701
• Publication Number:
  US 20040143341A1
• Time in Patent Office: 1,506 Days
• Field of Search: 623/20.12, 623/20.13, 623/20.24, 623/21.17, 623/22.15, 623/22.18, 623/22.19, 623/22.28, 623/22.38, 623/22.43, 623/23.35, 623/22.21, 623/22.4
• US Class Current: 623/22.15
• CPC Class Codes: A61F 2/32 for the hip
• CPC Class Codes: A61F 2/34 Acetabular cups
• 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 2/3676 Distal or diaphyseal parts of shafts
• CPC Class Codes: A61F 2/40 for shoulders
• CPC Class Codes: A61F 2/4241 for hands, e.g. fingers
• CPC Class Codes: A61F 2/4637 for connecting or disconnecting two parts of a prosthesis
• CPC Class Codes: A61F 2002/30187 D-shaped or half-disc-shaped
• CPC Class Codes: A61F 2002/30322 differing in surface structures
• 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 2002/30405 made by screwing complementary threads machined on the parts themselves
• CPC Class Codes: A61F 2002/30448 using adhesives
• CPC Class Codes: A61F 2002/30449 the adhesive being cement
• CPC Class Codes: A61F 2002/30477 using sharp protrusions, e.g. spikes, for anchoring into connecting prosthetic part
• CPC Class Codes: A61F 2002/30495 using a locking ring
• CPC Class Codes: A61F 2002/30652 Special cut-outs, e.g. flat or grooved cut-outs
• CPC Class Codes: A61F 2002/30685 Means for reducing or preventing the generation of wear particulates
• CPC Class Codes: A61F 2002/30827 Plurality of grooves
• CPC Class Codes: A61F 2002/3208 : Bipolar or multipolar joints, e.g. having a femoral head articulating within an intermediate acetabular shell whilst said shell articulates within the natural acetabular socket or within an artificial outer shell
• CPC Class Codes: A61F 2002/3216 : tripolar
• CPC Class Codes: A61F 2002/3233 : having anti-luxation means for preventing complete dislocation of the femoral head from the acetabular cup
• 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 2002/345 : the inner and outer (hemi)spherical surfaces of a shell, e.g. an intermediate shell, having distinct centres of rotation, both located on the centre line of the shell
• CPC Class Codes: A61F 2002/3493 : Spherical shell significantly greater than a hemisphere, e.g. extending over more than 200 degrees
• CPC Class Codes: A61F 2002/3611 : Heads or epiphyseal parts of femur
• CPC Class Codes: A61F 2002/3625 : Necks
• 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 2220/0033 : made by longitudinally pushing a protrusion into a complementary-shaped recess, e.g. held by friction fit
• CPC Class Codes: A61F 2220/005 : using adhesives
• CPC Class Codes: A61F 2230/0034 : D-shaped
• CPC Class Codes: A61F 2250/0026 : differing in surface structures
• CPC Class Codes: A61F 2310/00017 : Iron- or Fe-based alloys, e.g. stainless steel
• CPC Class Codes: A61F 2310/00023 : Titanium or titanium-based alloys, e.g. Ti-Ni alloys
• CPC Class Codes: A61F 2310/00179 : Ceramics or ceramic-like structures

Abstract

Methods, systems and devices for preventing prosthetic articulating surfaces from separating from each other. A containment system according to one embodiment seeks to prevent an implant stem head from dislocating from a prosthetic component while providing an increased range of motion over conventional contrained components. In one embodiment, an implant structural member includes a cavity and an opening having a lip, including a web along a portion of the lip. An implant stem head has a cooperating surface that corresponds with the web, so that when the cooperating surface of the implant stem head is aligned with the web, the head may be inserted into the implant structural member. The implant stem head is then rotated and the femoral stem component attached, thereby preventing dislocation of the head.

Claims

1. A containment system comprising:

(a) a shell, the shell comprising a cavity and an outside surface and including at least one opening on the outside surface providing access to the cavity;

(b) a liner, the liner comprising;

an outer surface;

a lip; and

an inner surface, the inner surface forming a cavity and including a web, wherein the web extends around a portion of the lip to form a D-shaped opening;

(c) an implant stem head, the implant stem head comprising;

a generally spherical body having a surface configured to correspond to the web enabling the implant stem head to be inserted into the liner when the implant stem head is in a first orientation; and

a cavity; and

(d) a separate femoral stem component which may be inserted into the cavity of the implant stem head,

wherein the shell may be received by an acetabulum, and

wherein the liner may be received in the cavity of the shell, and

wherein the web allows the implant stem head to be inserted into the cavity of the liner when the implant stem head is oriented in the first orientation and constrains the implant stem head within the cavity of the liner when the implant stem head is oriented in a second orientation such that the implant stem head may articulate within the liner but cannot be removed from the liner once it is attached to the stem.

2. A containment system comprising:

(a) a shell, the shell having a generally hemispherical shape and comprising a cavity and an outside surface and including at least one opening on the outside surface providing access to the cavity, wherein the shell is received by an acetabulum;

(b) a liner, the liner having a generally hemispherical shape and comprising;

an outer surface;

a lip; and

an inner surface, the inner surface forming a cavity and including a web, wherein the web extends around a portion of the lip to form a substantially D-shaped opening, and wherein the liner is received in the cavity of the shell and may articulate within the cavity of the shell;

(c) an implant stem head, the implant stem head comprising;

a generally spherical body having a substantially planar surface configured to correspond to the web enabling the implant stem head to be inserted into the liner when the implant stem head is in a first orientation; and

a cavity; and

(d) a separate femoral stem component which may be inserted into the cavity of the implant stem head,

wherein the inner surface of the liner is shaped to correspond generally to the outer surface of the implant stem head, and

wherein the web is shaped to cooperate with the implant stem head as the implant stem head articulates relative to the liner, and

wherein the web allows the implant stem head to be inserted into the cavity of the liner when the implant stem head is oriented in the first orientation and constrains the implant stem head within the cavity of the liner when the implant stem head is oriented in a second orientation such that the implant stem head may articulate within the liner but cannot be removed from the liner.

3. A containment system comprising:

(a) an implant structural member, the implant structural member comprising;

an outer surface;

a lip; and

an inner surface, the inner surface forming a cavity and including a web, wherein the web extends around a portion of the lip to form a substantially D-shaped opening;

(b) an implant stem head, the implant stem head comprising;

a generally spherical body having a substantially planar surface configured to correspond to the web enabling the implant stem head to be inserted into the implant structural member when the implant stem head is in the first orientation; and

a cavity; and

(c) a separate femoral stem component which may be inserted into the cavity of the implant stem head,

wherein the outer surface of the implant structural member may be received by a shell, and

wherein the implant stem head may be received by the implant structural member, and

wherein the web allows the implant stem head to be inserted into the cavity of the implant structural member when the implant stem head is oriented in a first orientation and constrains the implant stem head within the cavity when the implant stem head is oriented in a second orientation.