U.S. patent application number 17/750886 was filed with the patent office on 2022-09-01 for flexible acetabular implant.
This patent application is currently assigned to Smith & Nephew, Inc.. The applicant listed for this patent is Smith & Nephew Asia Pacific Pte. Limited, Smith & Nephew, Inc., Smith & Nephew Orthopaedics AG. Invention is credited to Stephen J. Lee, Jeffrey J. Shea.
Application Number | 20220273449 17/750886 |
Document ID | / |
Family ID | 1000006348796 |
Filed Date | 2022-09-01 |
United States Patent
Application |
20220273449 |
Kind Code |
A1 |
Lee; Stephen J. ; et
al. |
September 1, 2022 |
FLEXIBLE ACETABULAR IMPLANT
Abstract
An acetabular cage or device is disclosed. In one embodiment,
the acetabular cage includes a cup portion configured for
implantation in an acetabulum and a flange extending from the cup
portion. The flange including a first, bone contacting surface
configured to face bony tissue surrounding the acetabulum when the
cup portion is implanted into the acetabulum and a second, top
surface opposite the first surface. The flange includes a flexible
portion and a fixation portion, the fixation portion including one
or more fixation features configured to facilitate fixation of the
flange to the bony tissue surrounding the acetabulum. The flexible
portion is arranged and configured to enable the flange, and hence
the fixation portion, to move relative to the cup portion to
facilitate placement of the flange relative to the bony tissue.
Inventors: |
Lee; Stephen J.; (Memphis,
TN) ; Shea; Jeffrey J.; (Memphis, TN) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Smith & Nephew, Inc.
Smith & Nephew Orthopaedics AG
Smith & Nephew Asia Pacific Pte. Limited |
Memphis
Zug
Singapore |
TN |
US
CH
SG |
|
|
Assignee: |
Smith & Nephew, Inc.
Memphis
TN
Smith & Nephew Orthopaedics AG
Zug
Smith & Nephew Asia Pacific Pte. Limited
Singapore
|
Family ID: |
1000006348796 |
Appl. No.: |
17/750886 |
Filed: |
May 23, 2022 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
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17258920 |
Jan 8, 2021 |
11369476 |
|
|
PCT/US2019/040796 |
Jul 8, 2019 |
|
|
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17750886 |
|
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62696479 |
Jul 11, 2018 |
|
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
A61F 2002/30449
20130101; A61F 2002/3432 20130101; A61F 2/34 20130101; A61F
2002/30291 20130101; A61F 2002/3401 20130101; A61F 2/30724
20130101 |
International
Class: |
A61F 2/34 20060101
A61F002/34; A61F 2/30 20060101 A61F002/30 |
Claims
1. An acetabular cage, comprising: a cup portion configured for
implantation in an acetabulum; and a flange extending from the cup
portion, the flange including: a first surface and a second surface
opposite the first surface, the first surface arranged and
configured to contact a patient's bony tissue surrounding the
acetabulum when the cup portion is implanted into the acetabulum;
and a flexible region arranged and configured to enable the flange
to be movably positioned relative to the cup portion, the flexible
region including a plurality of flexible units, each of the
plurality of flexible units including a plurality of channels
extending from the first surface to the second surface.
2. The acetabular cage of claim 1, wherein the flange further
comprises one or more fixation features arranged and configured to
couple the flange to the bony tissue surrounding the
acetabulum.
3. The acetabular cage of claim 1, wherein the plurality of
channels include a first channel and a second channel spaced from
the first channel, and an isthmian strip positioned between the
first and second channels.
4. The acetabular cage of claim 3, wherein the plurality of
channels and the isthmian strip define a tortuous path along a
plane of the flange.
5. The acetabular cage of claim 3, wherein each of the first and
second channels include a first portion and a second portion angled
relative to the first portion.
6. The acetabular cage of claim 3, wherein the first channel is a
first linear channel and the second channel is a second linear
channel extending parallel to but spaced from the first linear
channel.
7. The acetabular cage of claim 6, wherein each of the first and
second linear channels include a first portion and a second portion
angled relative to the first portion.
8. The acetabular cage of claim 7, wherein at least one of the
first and second linear channels extends in a transverse
direction.
9. The acetabular cage of claim 7, wherein the first and second
linear channels are configured in a double spiral pattern such that
the isthmian strip is serpentine.
10. The acetabular cage of claim 3, wherein the isthmian strip
includes a plurality of solid portions positioned between adjacent
channels such that the channels facilitate relative movement of
adjacent solid portions.
11. An acetabular cage, comprising: a cup portion configured for
implantation in an acetabulum; and a flange extending from the cup
portion, the flange including: a first surface and a second surface
opposite the first surface, the first surface arranged and
configured to contact a patient's bony tissue surrounding the
acetabulum when the cup portion is implanted into the acetabulum;
one or more fixation features arranged and configured to couple the
flange to the bony tissue surrounding the acetabulum; and a
flexible region arranged and configured to enable the flange to be
movable positioned relative to the cup portion.
12. The acetabular cage of claim 11, wherein the flexible region
comprises a drapable chainmail structure comprising a plurality of
interlinked floating members so that the flexible region is
configured to conform to an overall geometry of the bony tissue
surrounding the acetabulum during use.
13. The acetabular cage of claim 12, wherein the plurality of
interlinked floating members are arranged and configured to
facilitate relative movement of adjacent floating members.
14. The acetabular cage of claim 12, wherein the chainmail
structure is configured to conform to the overall geometry of the
bony tissue without requiring further manual manipulation.
15. The acetabular cage of claim 12, wherein the plurality of
interlinked floating members includes a plurality of landings and a
plurality of interlinked hoops connecting the plurality of landings
with one another so that adjacent landings are movable with respect
to one another.
16. The acetabular cage of claim 15, wherein each of the plurality
of interlinked hoops is integrally formed with a corresponding one
of the landings.
17. The acetabular cage of claim 15, wherein the plurality of
interlinked hoops includes a plurality of first hoops and a
plurality of second hoops, wherein each of the plurality of first
hoops is connected with a corresponding one of the landings, each
of the plurality of second hoops is connected to adjacent first
hoops for coupling adjacent landings.
Description
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application is a continuation application of pending
U.S. patent application Ser. No. 17/258,920, filed Jan. 8, 2021,
entitled "Flexible Acetabular Implant," which is a United States
National Phase filing of International Application No.
PCT/US2019/040796, filed Jul. 8, 2019, which claims the benefit of
U.S. Provisional Patent Application Ser. No. 62/696,479, filed Jul.
11, 2018, entitled "Flexible Acetabular Implant," the entire
contents of which applications are hereby incorporated by reference
in their entirety.
FIELD OF INVENTION
[0002] The present disclosure generally relates to orthopedic
implants, and more particularly but not exclusively relates to
acetabular cage, device, apparatus, system, etc. (used
interchangeably herein) having a flexible region or portion for
facilitating improved placement.
BACKGROUND
[0003] Acetabular cage systems are typically used to address
acetabular defects in which large portions of a patient's medial
wall is missing. Acetabular cages generally include flanges that
are generally used to secure the cage to the patient's bony tissue
surrounding the acetabular defect and to provide the cage with
greater stability. As a result, the flanges are typically subjected
to high stresses due to anatomical loading.
[0004] In addition, often times, the surgeon needs to bend the
flanges so the cage is better-positioned to address the acetabular
defect for the case at hand. This bending, however, subjects the
flanges to additional stresses. Due to the high stresses that these
flanges are subjected to, be it through surgeon's bending or
repeated anatomical loading, they are common areas of fracture. For
these reasons among others, there remains a need for further
improvements in this technological field.
SUMMARY
[0005] This Summary is provided to introduce a selection of
concepts in a simplified form that are further described below in
the Detailed Description. This Summary is not intended to identify
key features or essential features of the claimed subject matter,
nor is it intended as an aid in determining the scope of the
claimed subject matter.
[0006] The present disclosure provides an acetabular cage. In one
embodiment, the acetabular cage comprises a cup portion configured
for implantation in an acetabulum and a flange extending from the
cup portion. The flange including: a first surface and a second
surface opposite the first surface, the first surface arranged and
configured to contact a patient's bony tissue surrounding the
acetabulum when the cup portion is implanted into the acetabulum;
one or more fixation features arranged and configured to couple the
flange to the bony tissue surrounding the acetabulum; and a
flexible region arranged and configured to enable the flange to be
movable positioned relative to the cup portion.
[0007] In some embodiments, the flexible region comprises a
drapable chainmail structure comprising a plurality of interlinked
floating members so that the flexible region is configured to
conform to an overall geometry of the bony tissue surrounding the
acetabulum during use.
[0008] In some embodiments, the plurality of interlinked floating
members are arranged and configured to facilitate relative movement
of adjacent floating members.
[0009] In some embodiments, the chainmail structure is configured
to conform to the overall geometry of the bony tissue without
requiring further manual manipulation.
[0010] In some embodiments, the plurality of interlinked floating
members includes a plurality of landings and a plurality of
interlinked hoops connecting the plurality of landings with one
another so that adjacent landings are movable with respect to one
another.
[0011] In some embodiments, each of the plurality of interlinked
hoops is integrally formed with a corresponding one of the
landings.
[0012] In some embodiments, the plurality of interlinked hoops
includes a plurality of first hoops and a plurality of second
hoops, wherein each of the plurality of first hoops is connected
with a corresponding one of the landings, each of the plurality of
second hoops is connected to adjacent first hoops for coupling
adjacent landings.
[0013] In some embodiments, the flexible region includes a
plurality of solid portions and a plurality of channels; each of
the solid portions positioned between adjacent channels such that
the channels facilitate relative movement of adjacent solid
portions.
[0014] In some embodiments, the plurality of channels extend into
and/or through the flange in a transverse direction and define at
least one tortuous path.
[0015] In some embodiments, the flexible region includes a
plurality of flexible units, each of the plurality of flexible
units including a plurality of channels and a plurality of isthmian
strips, the plurality of channels being formed within the flange,
the plurality of channels defining the plurality of isthmian
strips.
[0016] In some embodiments, the plurality of flexible units extend
between and connect the cup portion to the one or more fixation
features.
[0017] In some embodiments, the plurality of channels and the
plurality of isthmian strips define a tortuous path along a plane
of the flange.
[0018] In some embodiments, each of the plurality of flexible units
includes a portion of a first channel of the plurality of channels
and a portion of a second channel of the plurality of channels, the
first and second channels defining a portion of a first isthmian
strip of the plurality of isthmian strips.
[0019] In some embodiments, the first and second channels are
configured in a double spiral pattern such that the first isthmian
strip is serpentine.
[0020] In some embodiments, the flexible region includes a
plurality of channels extending into and/or through the flange in a
transverse direction; and a plurality of isthmian strips defined by
the plurality of channels, each of the plurality of isthmian strips
positioned between adjacent channels.
[0021] In some embodiments, the plurality of isthmian strips are
serpentine.
[0022] In some embodiments, the flexible region further includes at
least one groove operable to receive a flowable cement, wherein the
at least one groove is arranged such that a geometry of the
flexible region is retained upon hardening of the flowable
cement.
[0023] In some embodiments, the flexible region includes a
plurality of interconnected ball and sockets.
[0024] In some embodiments, the flange includes an angular span
centered about a central axis of the cup portion, wherein the
angular span is at least 60 degrees.
[0025] There is provided an acetabular cage, comprising: a cup
portion configured for implantation in an acetabulum; and a flange
extending from the cup portion and along a plane, the flange having
a first side surface configured to face bony tissue surrounding the
acetabulum when the cup portion is implanted to the acetabulum, the
flange having a second side surface opposite the first side
surface, wherein the first side surface and the second side surface
are offset from one another in a direction transverse to the plane,
the flange comprising a flexible portion and one or more fixation
features configured to facilitate fixation of the flange to the
bony tissue surrounding the acetabulum; wherein the flexible
portion includes a plurality of solid portions and a plurality of
channels; wherein the solid portions are defined between the
channels; and wherein the channels extend through the flange in the
transverse direction and define at least one tortuous path such
that the channels facilitate relative movement of adjacent segments
of the solid portions, the channels facilitating said relative
movement in the transverse direction and along the plane.
[0026] In some embodiments, the one or more fixation features may
be connected to the cup portion via the flexible portion such that
the flexible portion facilitates movement of the one or more
fixation features relative to the cup portion.
[0027] In some embodiments, the flange may have an angular span
centered about a central axis of the cup portion, wherein the
angular span is at least 60.degree., wherein the fixation portion
includes a plurality of the fixation features, and wherein the
plurality of fixation features are angularly spaced from one
another.
[0028] In some embodiments, the one or more fixation features may
comprise a plurality of the fixation features, wherein a first of
the fixation features is connected to a second of the fixation
features via the flexible portion such that the flexible portion
facilitates relative movement of the first fixation feature and the
second fixation feature.
[0029] In some embodiments, the one or more fixation features may
comprise at least one groove operable to receive a flowable cement,
wherein the at least one groove is arranged such that the flexible
is retained in a selected geometry upon hardening of the
cement.
[0030] In some embodiments, a first of the solid portions may
define a socket member, wherein a second of the solid portions
defines a ball member, and wherein the ball member is received in
the socket member such that a spheroid joint is formed between the
first solid portion and the second solid portion.
[0031] There is also provided an acetabular cage, comprising: a cup
portion configured for implantation in an acetabulum, the cup
portion having a rim; and a flange extending from the rim, the
flange having a first side configured to face bony tissue
surrounding the acetabulum when the cup portion is implanted to the
acetabulum, the flange having a second side opposite the first
side, wherein the flange comprises a flexible portion, the flexible
portion comprising a drapable chainmail structure comprising a
plurality of interlinked floating members.
[0032] In some embodiments, the plurality of interlinked floating
members may comprise a plurality of landings and a plurality of
interlinked hoops connecting the plurality of landings with one
another.
[0033] In some embodiments, one or more of the landings may
comprise a porous tissue ingrowth structure formed on the first
side.
[0034] In some embodiments, the chainmail structure may be
configured to adopt an overall geometry of the bony tissue
surrounding the acetabulum when draped over said bony tissue.
[0035] In some embodiments, the flexible portion further may
comprise at least one groove operable to receive a flowable cement,
wherein the at least one groove is arranged such that the chainmail
structure is retained in the adopted overall geometry upon
hardening of the flowable cement.
[0036] In some embodiments, the chainmail structure may be
configured to adopt an overall geometry of an object over which the
chainmail structure is draped.
[0037] In some embodiments, the chainmail structure may be
configured to adopt said overall geometry substantially without
requiring further manual manipulation.
[0038] In some embodiments, each of the hoops may be integrally
formed with a corresponding one of the landings.
[0039] In some embodiments, the plurality of hoops may comprise a
plurality of first hoops and a plurality of second hoops, wherein
each of the first hoops is integrally formed with a corresponding
one of the landings, wherein the second hoops are not integrally
formed with any of the landings, and wherein the first hoops are
interlinked with one another via the second hoops.
[0040] There is also provided an acetabular cage comprising a
flange extending from a rim, the flange having a first side surface
configured to face bony tissue surrounding the acetabulum when the
cup portion is implanted to the acetabulum, the flange having a
second side surface opposite the first side surface, wherein the
first side surface and the second side surface are offset from one
another in a transverse direction of the flange, the flange
comprising: a fixation portion including one or more features
configured to facilitate fixation of the fixation portion to the
bony tissue surrounding the acetabulum; a flexible portion
connected between the rim and the fixation portion, the flexible
portion comprising a plurality of isthmian strips, wherein each of
said isthmian strips extends between and connects the rim and the
fixation portion; and a plurality of channels, wherein each channel
extends through the flange in the transverse direction, and wherein
the channels define the plurality of isthmian strips.
[0041] In some embodiments, the isthmian strips may be
serpentine.
[0042] In some embodiments, the channels may form disconnected
plural-spiral patterns.
[0043] In some embodiments, the plural-spiral patterns may be
rectilinear.
[0044] In some embodiments, the isthmian strips may meet one
another at junctions, wherein the junctions are fenestrated.
[0045] In some embodiments, one or more of the channels may include
a first channel segment and a second channel segment extending from
the first channel segment at an angle.
[0046] Embodiments of the present disclosure provide numerous
advantages. For example, providing a flange having a flexible
region or portion facilitates placement of the flange relative to
the patient's bony tissue surrounding the acetabulum and thus
proper positioning of the fixation region and bone screws while
minimizing the associated stresses that these flanges are subjected
to either through a surgeon's bending or repeated anatomical
loading.
[0047] Further features and advantages of at least some of the
embodiments of the present invention, as well as the structure and
operation of various embodiments of the present invention, are
described in detail below with reference to the accompanying
drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0048] The description herein makes reference to the accompanying
figures wherein like reference numerals refer to like parts
throughout the several figures and views.
[0049] FIG. 1 is a perspective view of an example embodiment of an
acetabular cage in accordance with the present disclosure.
[0050] FIG. 2 is a side view of an example embodiment of a flange
used in the acetabular cage of FIG. 1, the flange including a
flexible structure in accordance with the present disclosure.
[0051] FIG. 3 is a plan view of the flange illustrated in FIG.
2.
[0052] FIG. 4 is an enlarged plan view of the flexible structure
illustrated in FIGS. 2 and 3.
[0053] FIG. 5 is a plan view of an alternate embodiment of a
flexible structure used in a flange in accordance with the present
disclosure.
[0054] FIG. 6 is an enlarged plan view of the flexible structure
illustrated in FIG. 5.
[0055] FIG. 7 is an enlarged side view of the flexible structure
illustrated in FIGS. 5 and 6.
[0056] FIG. 8 is a cross-sectional view of the flexible structure
illustrated in FIG. 5 draped over bony tissue surrounding an
acetabulum.
[0057] FIG. 9 is a perspective view of an alternate embodiment of a
flexible structure that may be utilized to form a flexible region
of a flange in accordance with the present disclosure.
[0058] FIG. 10 is a top, detailed view of the flexible structure
illustrated in FIG. 9.
[0059] FIG. 11 is a bottom, detailed view of the flexible structure
illustrated in FIG. 9.
[0060] FIG. 12 is a plan view of an alternate example embodiment of
a flange in accordance with the present disclosure.
[0061] FIG. 13 is a plan view of an alternate example embodiment of
a flange in accordance with the present disclosure.
[0062] FIG. 14 is a plan view of an alternate example embodiment of
an acetabular cage in accordance with the present disclosure.
[0063] FIG. 15 illustrates an alternate example embodiment of a
flexible structure in accordance with the present disclosure.
[0064] FIG. 16 is a cross-sectional view of an example embodiment
of a flange including the flexible structure illustrated in FIG.
15.
[0065] FIG. 17 is an exploded, perspective view of an example
embodiment of a use case scenario involving an acetabular cage in
accordance with the present disclosure.
[0066] FIG. 18 is a perspective view of an example embodiment of a
system in accordance with the present disclosure.
[0067] The foregoing summary, as well as the following detailed
description of certain embodiments of the present invention, will
be better understood when read in conjunction with the appended
drawings. For the purpose of illustrating the invention, there is
shown in the drawings, certain embodiments. It should be
understood, however, that the present invention is not limited to
the arrangements and instrumentalities shown in the attached
drawings. Additionally, the description herein makes reference to
the accompanying figures wherein like reference numerals refer to
like parts throughout the several views.
DESCRIPTION OF THE ILLUSTRATED EMBODIMENTS
[0068] Although the concepts of the present disclosure are
susceptible to various modifications and alternative forms,
specific embodiments have been shown by way of example in the
drawings and will be described herein in detail. It should be
understood, however, that there is no intent to limit the concepts
of the present disclosure to the particular forms disclosed, but on
the contrary, the intention is to cover all modifications,
equivalents, and alternatives consistent with the present
disclosure and the appended claims. That is, embodiments of an
improved acetabular apparatus will now be described more fully
hereinafter with reference to the accompanying drawings, in which
example embodiments of the present disclosure are presented. As
will be described and illustrated, in some embodiments, the
improved apparatus includes an acetabular apparatus including a cup
having one or more flanges. In various embodiments, as will be
described in greater detail, the flanges are adapted and configured
to provide increased flexibility to facilitate easier adaption of
the flanges to a patient's anatomy all the while reducing the
associated stresses with flexing, bending, etc. the flanges.
[0069] With reference to FIG. 1, illustrated therein is an
acetabular cage 100 according to certain embodiments. The
acetabular cage 100 generally includes a base or cup portion 110
configured to be seated in a prepared acetabulum of a surgical
patient, and one or more flanges 120 extending outwardly from a rim
112 of the cup portion 110. In use, the acetabular cage 100 may
include any number of flanges including a greater or lesser number
of flanges than illustrated. For example, it is envisioned that the
various cages may include one, two, three, four, or more flanges.
In addition, as will be shown and described, in various
embodiments, the flanges may be integrally formed with the base or
cup portion. However, as will be appreciated by one of ordinary
skill in the art, the flanges may be separately formed and coupled
to the base or cup portion by, for example, fasteners, cement, a
modular mechanism, etc. Moreover, flanges may be used without any
base or cup portion. In such embodiments, the flanges may be
attached directly to an acetabular shell via, for example,
fasteners, cement, a modular mechanism, etc.
[0070] The cup portion 110 may include one or more fastener holes
114 through which one or more fasteners such as, for example, bone
screws may be passed to secure the cup portion 110 within the
patient's acetabulum. The fastener holes 114 may have any
appropriate shape, configuration, etc. now known or hereafter
developed. For example, the fastener holes 114 may be locking or
non-locking. For example, the fastener holes 114 may include a
plurality of tabs for engaging a head portion of a fastener
inserted therein. While the illustrated fastener holes 114 are
substantially star-shaped, it is also contemplated that one or more
of the fastener holes 114 may have a different geometry. For
example, the fastener holes 114 may be threaded, with a single,
double, or triple lead, as examples. In some embodiments, there may
be two or more layers of tabs that form the star-shaped holes.
While five tabs are illustrated, the star-shaped holes may have as
few as three tabs or as many as eight tabs. Additional information
on the operation and configuration of the tab configuration for
engaging the head of the fastener in order to secure the fastener
at a desired position and at a desired angular orientation within
the opening can be found in U.S. Pat. No. 10,092,337 entitled
Systems and Methods for Using Polyaxial Plates.
[0071] In the illustrated embodiment, as will be readily
appreciated by one of ordinary skill in the art, the cup portion
110 is configured to receive a liner (not shown) that provides an
articular bearing surface. During use, the liner interfaces with a
head of a femoral component. In other forms, the cup portion 110
may be configured to interface with the femoral component directly,
or may be configured to interface with the femoral component via a
dual-mobility assembly that provides two distinct articular
interfaces.
[0072] With additional reference to FIG. 2, the flange 120 extends
outwardly from the rim 112, and in the illustrated form includes a
fixation portion or region 122 and a flexible portion or region 130
(portion or region used interchangeably without the intent to
limit) formed between the rim 112 and the fixation region 122. The
fixation region 122 includes one or more fixation features 124 that
facilitate fixation of the flange 120 to the bony tissue
surrounding the patient's acetabulum. In use, the fixation features
124 are substantially similar to the fasteners holes 114 described
above in connection with the cup portion 110. For example, as
illustrated, the fixation feature 124 is provided in the form of a
star-shaped fastener hole 125 (FIG. 3) similar to the
above-described fastener hole 114. It is also contemplated that one
or more of the fixation features 124 may take any other suitable
form now known or hereafter developed for coupling the flange to
the patient's bony tissue. By way of example, the fixation feature
124 may take the form of a recess or groove configured to receive a
flowable cement, or may take the form of an opening structured to
receive a pin.
[0073] The flange 120 has a bone-facing or lower side surface 126
and an opposite upper side surface 127, and a thickness dimension
216 of the flange 120 is defined as the distance between the lower
and upper side surfaces 126, 127. In certain embodiments, at least
a portion of the flange 120 may be provided with a porous tissue
ingrowth structure 128 formed on or defining the bone-facing
surface 126. While the illustrated porous tissue ingrowth structure
128 is shown confined to the fixation region 122, it is also
contemplated that at least a portion of the porous tissue ingrowth
structure 128 may be formed in the flexible region 130.
[0074] With additional reference to FIG. 3, the flange 120 has a
longitudinal length dimension 212, a lateral width dimension 214,
and the transverse thickness dimension 216. As used herein, the
terms "longitudinal," "lateral," and "transverse" may be used to
describe directions defined by a coordinate system 200 having three
mutually orthogonal axes, where the coordinate system is specific
to the flange 120 being described. For example, the coordinate
system illustrated in FIGS. 2 and 3 is specific to the flange 120
illustrated therein, and includes a longitudinal (X) axis 202 along
which the longitudinal length dimension 212 extends, a lateral (Y)
axis 204 along which the lateral width dimension 214 extends, and a
transverse (Z) axis 206 along which the thickness dimension 216
extends. With the flange 120 in a standardized orientation, the
flange 120 extends away from the rim 112 and along an imaginary
plane 208 that includes the longitudinal (X) axis 202 and the
lateral (Y) axis 204 with the transverse (Z) axis 206 being
orthogonal to the plane 208.
[0075] It is to be appreciated that these terms are used for ease
and convenience of description, and are without reference to the
orientation of the flange 120 relative to the environment or the
patient's anatomy. For example, while an element that is described
as extending in a lateral direction may extend in an anatomical
lateral/medial direction when the acetabular cage is implanted to
the patient, such an element may additionally or alternatively
extend in an anatomical superior/inferior direction and/or an
anatomical anterior/posterior direction. Furthermore, extension or
spacing along one direction or axis need not preclude extension or
spacing along another direction or axis. For example, elements that
are described as being longitudinally offset from one another may
also be offset from one another in the lateral and/or transverse
directions, or may be aligned with one another in the lateral
and/or transverse directions. The terms are therefore not to be
construed as limiting the subject matter disclosed herein to a
particular orientation, or as limiting the spacing and/or extension
of an element to a single direction unless specifically stated to
the contrary.
[0076] In use, the flexible region 130 couples the fixation region
122 to the cup portion 110 so that the fixation region 122 can be
moved relative to the cup portion 110 to facilitate better
placement of the fixation region 122. As illustrated in FIG. 3, in
one embodiment, the flexible region 130 includes a plurality of
channels 132 formed within the flange 120. As illustrated, the
channels 132 may cooperate to define a plurality of isthmian strips
136. In use, the isthmian strips 136 extend between and connect the
rim 112 of the cup portion 110 and the fixation region 122. Thus
arranged, the flexible region 130 includes a plurality of flexible
units 138, each of which includes portions of two or more channels
132, which cooperate to define a portion of an isthmian strip 136.
Each of the channels 132 includes a plurality of channel segments
133, each of the isthmian strips 136 includes a plurality of strip
segments 137, and each of the strip segments 137 is defined at
least in part by one or more of the channel segments 133. The
channels 132 extend into and/or through the thickness dimension 216
of the flange 120 such that a channel segment 133 formed between
two adjacent strip segments 137 separates the strip segments 137
from one another, thereby facilitating relative movement of the
strip segments 137. For example, FIG. 3 illustrates one flexible
unit 138' that has been deformed along the plane 208 by moving the
strip segments 137 of the flexible unit 138' relative to one
another and relative to the strip segments 137 of an adjacent
flexible unit 138. While the isthmian strips 136 are illustrated as
generally linear, other geometries may be used. For example,
arcuate segments may be used. Further, while the channels are
illustrated as generally linear, other geometries may be used. For
example, a series of small holes may be used to form each
channel.
[0077] With additional reference to FIG. 4, illustrated therein is
an example flexible unit 140, which corresponds to the flexible
units 138 illustrated in FIG. 3. The flexible unit 140 includes a
portion of a first channel 142 and a portion of a second channel
144, which cooperate to define a portion of an isthmian strip 146.
As illustrated, in one embodiment, the first and second channels
142, 144 may be generally configured in a double spiral pattern
such that the isthmian strip 146 is serpentine, although other
configurations are envisioned. In the illustrated embodiment, the
first and second channels 142, 144 are provided in the form of
disconnected rectilinear spirals, such that the isthmian strip 146
is also rectilinear. In other forms, the first and second channels
142, 144 may be curvilinear or include curvilinear portions such
that the isthmian strip 146 includes one or more curvilinear edges.
Furthermore, while the spiral geometries illustrated herein are
double-spiral geometries, it is also contemplated that other forms
of plural-spiral geometries may be utilized, such as triple-spiral
geometries or quadruple-spiral geometries.
[0078] In certain forms, the flexible units 140 may be fundamental
repeating structures that are replicated to define the flexible
region 130. For example, FIG. 4 illustrates a pattern of four
flexible units 140 in which two of the flexible units 140 are
rotated 90.degree. relative to the other two flexible units 140. As
a result, the isthmian strips 146 of the flexible units 140 meet
one another at a junction 149. In certain embodiments, the junction
149 may be fenestrated, for example with a window 149'.
[0079] As will be appreciated, the type of flexibility provided by
a particular channel depends in part upon the orientation of the
channel relative to the overall flexible portion 130. Typically, a
channel segment extending in one direction within a plane will
provide shear flexibility in that direction and extension
flexibility in a perpendicular direction. For example, the
longitudinally extending channel segments 143 provide longitudinal
shear flexibility and lateral extension flexibility, whereas the
laterally-extending channel segments 145 provide longitudinal
extension flexibility and lateral shear flexibility. As will be
appreciated, both types of channel segments also may provide for
transverse shear flexibility. Thus, the geometry of the flexible
portion 130 facilitates deformation of the flexible portion 130 in
three dimensions, as well as bending of the flexible portion about
several different rotational axes.
[0080] In the illustrated form, the first and second channels 142,
144 and the isthmian strips 146 are generally aligned with the
longitudinal and lateral directions. It is also contemplated that
one or more sets of first and second channels 142, 144 and isthmian
strips 146 may extend at oblique angles relative to the
longitudinal and lateral directions. Additionally, the illustrated
longitudinal channel segments 143 run parallel to one another and
perpendicular to the laterally-extending channel segments 145 such
that the isthmian strips 146 are of generally constant widths.
However, it is also contemplated that the width of an isthmian
strip 146 may vary, for example in embodiments in which the
channels defining the strip run at oblique angles relative to one
another.
[0081] In the flange 120 illustrated in FIG. 3, the flexible
portion 130 includes four columns and five rows of flexible units
138. As will be appreciated, the number of rows and columns
appropriate for a particular flange 120 may vary based upon a
number of factors, including the dimensions of the flexible units
138 and the desired dimensions of the flexible region 130. In
certain embodiments, the number of rows and/or columns of units may
be fractional. For example, the leftmost flange 120 illustrated in
FIG. 1 includes three columns, one full row, and a portion of a
second row.
[0082] While the illustrated flexible region 130 includes repeating
flexible units 138, it is to be appreciated that other forms are
contemplated for the flexible region 130. By way of example, the
pattern defining the channels 132 and the isthmic strips 136 for
one or more flexible units 138 may be subjected to a controlled
randomization. As another example, the pattern defining the
channels 132 and the isthmian strips 136 for the overall flexible
region 130 may be subjected to controlled randomization, and
repeating or modular unit sections may be omitted.
[0083] Regardless of the precise configuration of the flexible
region 130, the channels 132 and the isthmian strips 136 may define
tortuous paths in the plane 208 along which the flange 120 extends,
and the width of each isthmian strip 136 is significantly less than
the overall lateral width dimension 214 of the flange 120. As a
result, each individual isthmian strip 136 has a significantly
lower cross-sectional area than the flange 120 as a whole, which
facilitates the deformation of the flexible region 130 to a desired
geometry. Additionally, the channels 132 provide natural points of
separation between the isthmian strips 136, thereby further
facilitating manipulation of the isthmian strips 136 and the flange
120 as a whole. These factors among others cooperate to render the
flanges 120 significantly easier for the surgeon to bend to a
desired shape that conforms to the patient's anatomy, and may
further increase the fidelity with which the deformed flexible
portion or region 130 conforms to the overall geometry of that the
selected bone surface. For example, during implantation, the
flexibility of the flexible region 130 as a result of the channels
132 and isthmian strips 136 facilitates the manual manipulation of
the flexible region 130 to a geometry that conforms to that of the
object on which it is positioned. That is, during implantation, in
order to facilitate positioning of the flange relative to base or
cup portion (e.g., positioning of the fixation region 122) manual
manipulation of the flexible region is needed (force of gravity is
generally insufficient to cause the flexible region to adopt to the
overall geometry of the patient). This characteristic of
facilitated deformation may be referred to herein as pliability,
and flexible structures exhibiting such pliability may be referred
to herein as pliable.
[0084] With reference to FIG. 5, an alternate example embodiment of
a flange 300 having a flexible region 310 according to certain
embodiments is shown. Like the above-described flexible region 130,
the flexible region 310 includes solid portions 316 having openings
or channels 312 formed therebetween to facilitate relative movement
of the solid portions 316. In the current embodiment, however, the
solid portions 316 are provided in the form of interlinked floating
members 316 that define a chainmail structure 320. As described
herein, the solid portions or floating members 316 are generally
disconnected from one another such that relative movement of the
floating members 316 is permitted, but are interlinked with one
another such that the relative movement of adjacent floating
members 316 is limited.
[0085] The floating members 316 may be coupled to each other by any
suitable mechanism now known or hereafter developed to facilitate
relative movement between the floating members 316 so that the
flexible region 310 enables relative movement of the fixation
region relative to the cup portion. For example, with additional
reference to FIGS. 6 and 7, which illustrate additional views of
the chainmail structure 320 illustrated in FIG. 5, the chainmail
structure 320 may include a plurality of landings 322 and a
plurality of interlinked hoops 325 by which the landings 322 are
linked to one another. Each landing 322 includes a plurality of
base hoops 323, each of which faces a base hoop 323 of an adjacent
landing 322. The base hoops 323 of adjacent landings 322 are linked
to one another via one or more floating hoops 326, which are not
necessarily formed on landings 322. As a result, relative movement
of the interlinked floating members 316 is permitted, but is
restricted to a limited range.
[0086] With additional reference to FIG. 8, the disconnected but
interlinked nature of the floating members 316 provides the
flexible region 310 with a different type of flexibility as
compared to the flexibility provided by the isthmian strips 136 of
the above-described flexible region 130. More specifically, the
fact that the floating members 316 are in a sense disconnected from
one another enables some free movement of the floating members 316
without requiring deformation of the material. Thus, when the
chainmail structure 320 is draped over an object, such as the bony
tissue 92 surrounding the acetabulum 94, the force of gravity
causes the chainmail structure 320 to adopt the overall geometry of
the flexible region 310 substantially without requiring further
manual manipulation. This characteristic may be referred to herein
as drapability, and flexible structures exhibiting such a
characteristic may be referred to herein as drapable.
[0087] In the illustrated embodiment, each channel 312 is
substantially straight such that the landings 322 are substantially
square. However, due to the interconnected nature of the channels
312, the channels, when taken together, define tortuous paths
within the plane along which the flange 300 extends when in the
standard orientation. Furthermore, it is to be appreciated that the
landings 322 may have different arrangements and/or geometries from
those illustrated in the Figures. As one example, square landings
may be offset from one another to provide for channels that exhibit
a step-like geometry. As another example, the landings may be
provided with a hexagonal geometry such that the channels exhibit a
honeycomb-like geometry. In further embodiments, the landings 322
may be omitted from one or more portions of the chainmail structure
320 such that that portion is comprised entirely of interlinked
floating hoops 326.
[0088] In addition to contributing to the drapability of the
chainmail structure 320, the channels 312 may serve additional
functions that facilitate the implantation of an acetabular cage
including the flange 300. For example, once the flexible region 310
has been draped over the target surface and adopted the geometry
thereof, a flowable cement may be introduced to the channels 312.
Upon hardening, the cement locks the previously flexible chainmail
structure 320 in the desired configuration, and may further aid in
securing the flange 300 to the bony tissue surrounding the
acetabulum. Thus, the channels 312 themselves may be considered to
define fixation features configured to facilitate fixation of the
flange 300 to the bony tissue surrounding the acetabulum.
[0089] With reference to FIGS. 9-11, an alternate embodiment of a
chainmail structure 350 that may be utilized to form a drapable
portion of a flange is illustrated. Like the above-described
chainmail structure 320, the illustrated chainmail structure 350
includes a plurality of interlinked floating members 352 having
channels 354 defined therebetween. As illustrated, the floating
members 352 include landings 356, which may have a porous tissue
ingrowth structure formed on the bone-facing sides thereof. Formed
on the opposite side of the landings 356 (e.g., bone-facing side of
the landings 356) are hoops 358 that interlink the floating members
352 such that the chainmail structure 350 is drapable. In contrast
to the above-described chainmail structure 320, however, the
chainmail structure 350 does not necessarily include floating
hoops. Instead, each of the hoops 358 may be integrally formed with
a corresponding one of the landings 356, and the hoops 358 of
adjacent landings 356 are directly interlinked with one
another.
[0090] With reference to FIGS. 12-14, alternate embodiments of
acetabular cages according to present disclosure are illustrated.
Each of the acetabular cages generally includes a base or cup
portion 110 and one or more flanges extending therefrom, each of
the flanges including a flexible region. In FIGS. 12-14, the
flexible regions are generally indicated with a pattern of dashed
lines, where the dashed lines schematically represent openings or
channels that extend into and/or through the thickness of the
flange. It is to be appreciated that the configurations of the
flexible regions are not intended to be limited to the schematic
representations thereof, and that such flexible regions may take
any of a number of forms. In certain forms, the flexible regions
may be provided as a pliable region, such as the pliable regions
described with reference to FIGS. 1-4. In other embodiments, the
flexible regions may be provided as a drapable region, such as the
drapable regions described with reference to FIGS. 5-11. It is
further contemplated that a flexible region may include both
pliable regions and drapable regions. As such, the flexible regions
described hereinafter are to be understood as not being limited to
the particular patterns illustrated in the Figures.
[0091] Additionally, as previously described, each of the flanges
described hereinafter may include one or more fixation features
that facilitate the fixation of the flange to the bony tissue
surrounding the acetabulum. While the fixation features are
illustrated in the Figures as being provided in the form of
star-shaped openings, it is to be appreciated that other forms of
fixation features may be utilized. By way of example, one or more
fixation features may take the form of a threaded opening for
receiving a threaded fastener. Alternatively, one or more fixation
features may take the form of a recess or groove configured to
receive a flowable cement, or may take the form of an opening
structured to receive a fixation pin. As such, the fixation
features referred to hereinafter are to be understood as not being
limited to the particular features illustrated in the Figures.
[0092] With reference to FIG. 12, illustrated therein is a flange
400 according to certain embodiments. The flange 400 extends from a
rim 410 and generally includes a fixation region 420 and a flexible
region 430 connecting the rim 410 with the fixation region 420. The
fixation region 420 includes one or more fixation features 422
configured to facilitate fixation of the flange 400 to the bony
tissue surrounding the acetabulum. In the illustrated form, the
fixation region 420 is substantially rigid, and resists relative
movement of the fixation features 422. It is also contemplated that
the fixation region 420 may include one or more flexible portions,
for example as described below with reference to FIG. 13. In such
forms, the additional flexible portions may facilitate relative
movement of the fixation features 422.
[0093] In addition to a flexible structure such as any of those
described herein, the flexible region 430 may also include a
fixation feature in the form of a channel or groove 432. The groove
432 is configured to receive a flowable cement 433 which, upon
hardening, at least partially locks the flexible region 430 in the
selected configuration. In the illustrated form, the groove 432 and
the rim 410 cooperate to generally surround the flexible region 430
such that upon hardening of the cement 433, the outer boundary of
the flexible region 430 becomes fixed, while the flexible region
430 remains flexible in the transverse direction. In other forms,
one or more grooves may be arranged such that upon hardening of the
cement, the geometry of the flexible region 430 is fixed. For
example, such grooves may be connected to the channels of the
flexible region 430 such that the flowable cement infiltrates the
channels and freezes the overall geometry of the flexible region
430. It is also contemplated that the groove 432 may be
disconnected from the channels to discourage infiltration of the
cement into the channels. For example, in embodiments in which the
flexible region 430 includes a porous tissue ingrowth structure, it
may be undesirable to have the cement infiltrate the tissue
ingrowth structure, and the groove 432 may remain disconnected from
the channels to discourage such infiltration.
[0094] With reference to FIG. 13, illustrated therein is a flange
500 according to certain embodiments. The flange 500 extends from a
rim 510 and generally includes an integrated region that includes a
plurality of fixation regions 520 and a flexible region 530. In
use, each fixation region 520 is substantially solid to provide for
increased structural strength, which also renders the fixation
regions 520 substantially rigid. However, the fixation regions 520
are connected to one another via the flexible region 530 (e.g., the
fixation regions 520 may be dispersed within the flexible region
530), which facilitates relative movement of the fixation regions
520. As a result, the position and/or orientation of the fixation
regions 520 can be independently adjusted, for example to more
fully seat against a desired portion of the bony tissue surrounding
the acetabulum.
[0095] With reference to FIG. 14, illustrated therein is an
acetabular cage 100' according to certain embodiments. The
acetabular cage 100' includes a base or cup portion 110 having a
rim 112 such as those previously described herein. In addition, the
cage 100' includes a flange 600. Like the above described flange
500, the flange 600 may include a plurality of fixation regions 620
dispersed within a flexible region 630 for connecting the fixation
regions 620 to the cup portion 110. However, in contrast to
previously described flanges, the flange 600 has a significantly
greater angular span .theta.600 than the above-described flanges
such that the flange 600 spans at least the majority of that
portion of the rim that faces the anatomical superior direction
when the acetabular cage 100' is implanted to the patient. The
angular span .theta.600 is measured as the central angle subtended
by the flange 600 relative to the central axis 119 of the cup
portion 110. In the illustrated form, the angular span .theta.600
is defined at the rim 112, is greater than 90.degree., and more
specifically is about 120.degree.. It is also contemplated that the
angular span .theta.600 may be measured relative to another set of
end points of the flange 600, such as the points 602 at which the
lateral width of the flange 600 is greatest. In such forms, the
angular span .theta.600 may be 90.degree. or less. In either event,
the angular span .theta.600 may be greater than 60.degree. to
provide for suitable coverage of the bony tissue surrounding the
acetabulum. While FIG. 14 illustrates and describes a flange
similar to flange 500, it is envisioned that flange 600 may be
arranged and configured with fixation regions 620 and flexible
regions 630 similar to those of other described embodiments. For
example, the flexible region may include a chainmail structure, a
plurality of channels and isthmian strips, etc.
[0096] With reference to FIGS. 15 and 16, illustrated therein is an
alternate example embodiment of a flexible structure 700. As
illustrated, the flexible structure 700 is provided in the form of
a ball-and-socket structure 700 including one or more spheroid
joints 710. The ball-and-socket structure 700 may also be referred
to herein as the spheroid joint structure 700. Each joint 710
includes a socket member 712 and a ball member 714 pivotably
received in the socket member 712. As will be readily appreciated
by one of ordinary skill in the art, the ball-and-socket structure
enables relative movement of the fixation region 752 located on one
side of the ball-and-socket structure relative to the base or cup
portion located on the other.
[0097] In one embodiment, each joint 710 is defined by two links
720, one of which defines the socket member 712 and the other of
which defines the ball member 714. The socket member 712 is
disconnected from the ball member 714 such that a tortuous channel
716 extends through the thickness of the structure 700.
[0098] Referring to FIG. 16, the flange 750 includes a fixation
region 752 that is connected to the rim of the cup via a flexible
region 754 that includes the spheroid joint structure 700. The
joint structure 700 includes a plurality of links 760 that includes
a base link 762 and an end link 764, and which may further include
one or more intermediate links 766. The base link 762 is formed at
the rim of the cup, and the end link 764 defines at least a portion
of the fixation region 752 and includes a fixation feature 757 in
the form of an opening.
[0099] Each of the links 760 includes a socket member 712 and/or a
ball member 714. In the illustrated form, the base link 762
includes a socket member 712, the end link 764 includes a ball
member 714, and each of the intermediate links 766 includes both a
socket member 712 and a ball member 714. However, it is to be
appreciated that other forms are contemplated. For example, the
base link 762 may include a ball member and/or the end link 764 may
include a socket member. As another example, one or more
intermediate links 766 may include two ball members, each of which
is engaged with a socket member of an adjacent link. As a further
example, one or more intermediate links 766 may include two socket
members, each of which is engaged with a ball member of an adjacent
link.
[0100] In the illustrated form, the flexible region 754 is formed
of one or more spheroid joint structures 700. By way of example,
several of the structures 700 may be positioned next to one another
to define strands that extend between and connect the cup portion
(e.g., rim) and the fixation region 752. In certain forms, the
strands may be disconnected such that the strands are free to move
relative to one another. In other forms, a link of one strand may
be integral with a link of an adjacent strand such that the strands
move at least partially in unison.
[0101] In certain embodiments, a spheroid joint structure may be
used in combination with another form of flexible structure. By way
of example, a line of spheroid joints 710 may be formed at the rim,
and may connect the rim with a flexible structure such as the
flexible region 130. In such forms, each joint 710 may, for
example, be associated with a corresponding and respective isthmian
strip. In other embodiments, the line of spheroid joints may form
one or more hinges such that one or more of the end links 764 is
directly engaged with a corresponding base link 762.
[0102] As is evident from the foregoing, the flanges described
herein are capable of providing greater flexibility than
conventional flanges, which facilitates the process of conforming
the flanges to the bony tissue surrounding the acetabulum. This
flexibility may also increase the fidelity with which the flange
conforms to the bony tissue, which may improve long-term outcomes
for the patient.
[0103] Additionally, the flexibility of the flexible structures
described herein is due at least in part to the geometry of those
structures. As a result, these flexible structures may be formed of
materials having greater strength than those typically employed in
flanges for which flexibility is desired. For example, certain
conventional acetabular cages include flanges that are formed of
commercially pure titanium, which has a lower strength and is thus
more flexible than certain titanium alloys. While the structures
described herein can be formed of such commercially pure titanium,
the geometry-based flexibility of the structures may enable the
structures to retain the desired degree of flexibility when formed
of a stronger material, such as a titanium alloy. Such stronger
materials will typically exhibit increased resistance to wear,
which may further improve long-term outcomes for the patient.
[0104] In certain embodiments, the flexible structures described
herein may be manufactured according to conventional techniques,
such as those that involve forging, stamping, and/or fusing. In
other forms, the flexible structures may be manufactured according
to additive manufacturing techniques, such as selective laser
sintering (SLS) or direct metal laser sintering (DMLS). One
advantage of such additive manufacturing techniques is the
capability to create complex structures that may not necessarily be
feasible with traditional techniques. For example, while the
chainmail structure illustrated in FIGS. 8-10 and/or the ball and
socket structure illustrated in FIGS. 15 and 16 may be difficult or
infeasible to manufacture with conventional techniques, such
structures can often be additively manufactured with relative ease.
Additionally, the orthopaedic implant may be a unitary or integral
structure. In other words, the entire structure may be formed with
additive manufacturing techniques, or components may be made first
and form a substrate on which portions of the structure is
additively manufactured.
[0105] With reference to FIG. 17, illustrated therein is an example
use case scenario 800 involving an acetabular cage 810 according to
certain embodiments. The cage 810 includes a cup portion 812 and at
least one flange 814 extending from the cup portion 812. Each
flange 814 includes a flexible structure 815 that may, for example,
be provided as one or more of the flexible structures disclosed
herein. The cage 810 is configured for implantation to a hip 820
having an acetabulum 822 which is surrounded by bony tissue 824.
More particularly, the cup portion 812 is configured to be seated
in the acetabulum 822, and the flanges 814 are configured to engage
the bony tissue 824 when the cup portion 812 is seated in the
acetabulum 822. Additionally, the flexible structures 815 provide
the flanges 814 with a degree of flexibility that facilitates the
process of conforming the flanges 814 to the irregular shape of the
bony tissue 824, thereby increasing the area of contact between the
flange 814 and the bony tissue 824. This increased area of contact
may facilitate the fixation of the flanges 814 to the bony tissue
824, for example when such fixation involves the use of cement or
tissue ingrowth into a porous structure formed on the bone-facing
side of the flange 814.
[0106] In the use case scenario 800, the femur 830 of the patient
has been resected, and the proximal end portion of the femur 830
has been replaced with a prosthetic hip stem 840 having a femoral
head component 850 mounted thereon. Disposed between the acetabular
cage 810 and the femoral head component 850 is a liner 860. The
liner 860 has an outer surface 862 configured to be seated in the
cup portion 812 of the cage 810, and to couple with the inner
surface of the cup portion 812. By way of example, the outer
surface 862 of the liner 860 may have a first engagement feature,
such as a ridge and/or a groove, and the inner surface of the cup
portion 812 may have a mating engagement feature, such as a groove
and/or a ridge. The liner 860 also has an inner bearing surface 864
configured to receive the femoral head component 850 such that the
outer surface of the femoral head component 850 and the inner
bearing surface 864 define an articular interface. In certain
embodiments, the cage 810, the hip stem 840, the femoral head
component 850, and the liner 860 may be provided in a kit 870.
[0107] Additionally, while the flexible structures have been
illustrated as being integrally formed with the cup portion, it is
to be appreciated that other forms are contemplated. By way of
example, a "cup-cage" technique may be utilized, in which the cup
portion and the flexible flanges are formed as distinct and
separable components. In such forms, the cup portion may be
provided as a conventional acetabular cup, and one or more separate
components including the flexible flange or flanges may be secured
to the cup by any suitable mechanism now known or hereafter
developed including, for example, using fasteners such as screws,
cement, etc.
[0108] With additional reference to FIG. 18, illustrated therein is
an acetabular cup-cage system 900 according to certain embodiments.
The system 900 generally includes a cup portion 910 and a cage
portion 920 that is separate and distinct from the cup portion 910.
The cup portion 910 may, for example, be a conventional acetabular
cup having a generally hemispherical geometry. The cage portion 920
includes a base 921 that is configured to conform to the internal
geometry of the cup portion 910. The cage portion 920 may be
secured to the cup portion 910 using fasteners such as screws 902.
When so secured, a rim 922 of the cage portion 920 is adjacent and
abuts the rim 912 of the cup portion 910. The cage portion 920
further includes a flange 924 that extends from the rim 922, and
which includes a fixation region 926 and at least one flexible
region 928 connecting the rim 922 with the fixation region 926. The
flange 924 may, for example, be substantially similar to one or
more the flanges described hereinabove.
[0109] In the illustrated embodiment, the rim 922 of the cage
portion 920 is solid and conforms closely to the geometry of the
rim 912 of the cup portion 910. Additionally, the boundary between
the flexible region 928 and the solid portion of the cage rim 922
is curved, and more particularly exhibits a curvature that
corresponds to that of the cup rim 912. As a result, the cage
portion 920 exhibits structural rigidity in those regions that abut
the cup rim 912 while increasing the flexibility of those regions
that do not abut the cup rim 912.
[0110] While the flexible structures are illustrated herein as
being incorporated into an acetabular cage, it is to be appreciated
that the flexible structures described herein may be incorporated
into other orthopaedic implants. As examples, the flexible
structures could be incorporated into the glenoid portion of a
shoulder implant or bone plate for trauma or spinal
applications.
[0111] While the present disclosure refers to certain embodiments,
numerous modifications, alterations, and changes to the described
embodiments are possible without departing from the sphere and
scope of the present disclosure, as defined in the appended
claim(s). Accordingly, it is intended that the present disclosure
not be limited to the described embodiments, but that it has the
full scope defined by the language of the following claims, and
equivalents thereof. The discussion of any embodiment is meant only
to be explanatory and is not intended to suggest that the scope of
the disclosure, including the claims, is limited to these
embodiments. In other words, while illustrative embodiments of the
disclosure have been described in detail herein, it is to be
understood that the inventive concepts may be otherwise variously
embodied and employed, and that the appended claims are intended to
be construed to include such variations, except as limited by the
prior art.
[0112] The foregoing discussion has been presented for purposes of
illustration and description and is not intended to limit the
disclosure to the form or forms disclosed herein. For example,
various features of the disclosure are grouped together in one or
more embodiments or configurations for the purpose of streamlining
the disclosure. However, it should be understood that various
features of the certain embodiments or configurations of the
disclosure may be combined in alternate embodiments, or
configurations.
[0113] As used herein, an element or step recited in the singular
and proceeded with the word "a" or "an" should be understood as not
excluding plural elements or steps, unless such exclusion is
explicitly recited. Furthermore, references to "one embodiment" of
the present disclosure are not intended to be interpreted as
excluding the existence of additional embodiments that also
incorporate the recited features.
[0114] The use of "including," "comprising," or "having" and
variations thereof herein is meant to encompass the items listed
thereafter and equivalents thereof as well as additional items.
Accordingly, the terms "including," "comprising," or "having" and
variations thereof are open-ended expressions and can be used
interchangeably herein. The phrases "at least one", "one or more",
and "and/or", as used herein, are open-ended expressions that are
both conjunctive and disjunctive in operation. For example, each of
the expressions "at least one of A, B and C", "at least one of A,
B, or C", "one or more of A, B, and C", "one or more of A, B, or C"
and "A, B, and/or C" means A alone, B alone, C alone, A and B
together, A and C together, B and C together, or A, B and C
together.
[0115] All directional references (e.g., proximal, distal, upper,
lower, upward, downward, left, right, lateral, longitudinal, front,
back, top, bottom, above, below, vertical, horizontal, radial,
axial, clockwise, and counterclockwise) are only used for
identification purposes to aid the reader's understanding of the
present disclosure, and do not create limitations, particularly as
to the position, orientation, or use of this disclosure. All
rotational references describe relative movement between the
various elements. Connection references (e.g., engaged, attached,
coupled, connected, and joined) are to be construed broadly and may
include intermediate members between a collection of elements and
relative movement between elements unless otherwise indicated. As
such, connection references do not necessarily infer that two
elements are directly connected and in fixed relation to each
other. Identification references (e.g., primary, secondary, first,
second, third, fourth, etc.) are not intended to connote importance
or priority but are used to distinguish one feature from another.
The drawings are for purposes of illustration only and the
dimensions, positions, order and relative sizes reflected in the
drawings attached hereto may vary.
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