U.S. patent application number 16/422300 was filed with the patent office on 2019-10-17 for convertible glenoid.
The applicant listed for this patent is Zimmer, Inc.. Invention is credited to Andrew Rolfe Hopkins.
Application Number | 20190314161 16/422300 |
Document ID | / |
Family ID | 55752807 |
Filed Date | 2019-10-17 |
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United States Patent
Application |
20190314161 |
Kind Code |
A1 |
Hopkins; Andrew Rolfe |
October 17, 2019 |
CONVERTIBLE GLENOID
Abstract
A glenoid system (100) includes a baseplate (102) configured to
attach to a glenoid cavity of a patient. In a primary
configuration, a biocompatible plastic liner (332) can snap into a
circumferential groove (120) on the baseplate, to attach to a
lateral-facing surface (104) of the baseplate, at one or more
locations around the groove. In a reverse configuration, a
glenosphere (544, 644) can attach to an adapter (542, 642), which
in turn can attach to the lateral-facing surface of the baseplate.
The adapter can introduce lateral and/or angular offsets between
the baseplate and the glenosphere, which can correct for unwanted
offsets or inclinations. A middle peg extension (752) can screw
onto a medial end of the middle peg (114), which can offer
different combinations of peg length and peg material. The
baseplates can be made available in various discrete sizes, each of
which has the same distance between the middle peg and an inferior
screw hole (112).
Inventors: |
Hopkins; Andrew Rolfe;
(Winterthur, CH) |
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Applicant: |
Name |
City |
State |
Country |
Type |
Zimmer, Inc. |
Warsaw |
IN |
US |
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|
Family ID: |
55752807 |
Appl. No.: |
16/422300 |
Filed: |
May 24, 2019 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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15564636 |
Oct 5, 2017 |
10342669 |
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PCT/US2016/026106 |
Apr 6, 2016 |
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16422300 |
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62144031 |
Apr 7, 2015 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
A61F 2002/30616
20130101; A61F 2002/30405 20130101; A61F 2002/30878 20130101; A61F
2/4081 20130101; A61F 2002/305 20130101; A61F 2002/30607 20130101;
A61F 2002/30772 20130101; A61F 2002/4619 20130101; A61F 2002/30822
20130101; A61F 2002/30884 20130101; A61F 2002/30332 20130101; A61F
2002/4085 20130101 |
International
Class: |
A61F 2/40 20060101
A61F002/40 |
Claims
1. A glenoid system, comprising: a baseplate configured to attach
to a glenoid cavity of a patient, the baseplate defining a
lateral-facing surface extending from a superior end of the
baseplate to an inferior end of the baseplate, the lateral-facing
surface facing laterally when the baseplate is attached to the
glenoid cavity, the baseplate defining a superior hole through the
lateral-facing surface proximate the superior end of the baseplate,
the baseplate defining an inferior hole through the lateral-facing
surface proximate the inferior end of the baseplate, and the
baseplate being coupled to a middle peg at a middle area between
the inferior and superior holes, the middle peg extending medially
from the baseplate when the baseplate is attached to the glenoid
cavity; and an adapter having a first taper, the first taper being
a male taper sized and shaped to form a taper fit with a recess in
the middle peg, the adapter further having a second taper offset
from the first taper, and the second taper being size and shaped to
form a taper fit with a glenosphere or a glenoid shield.
Description
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application claims the benefit of U.S. Provisional
Application No. 62/144,031, titled "Convertible Glenoid", filed
Apr. 7, 2015, the entirety of which is hereby incorporated by
reference.
BACKGROUND
[0002] Shoulder arthroplasty is a surgical procedure in which all
or part of the glenohumeral joint is replaced by one or more
prosthetic implants. Frequently, shoulder arthroplasty is performed
to relieve pain due to severe arthritis or severe joint damage.
There is ongoing effort to improve the prosthetic components
utilized in this surgical procedure.
OVERVIEW
[0003] In a natural glenohumeral (shoulder) joint, the glenoid
cavity of the scapula (shoulder blade) is concavely curved. The
head of the humerus (upper arm bone) is convexly curved, is held
against the glenoid cavity, and can pivot in two dimensions around
its center of curvature.
[0004] A prosthetic shoulder system can include elements that
retain the same concavity of the natural joint. For instance, a
prosthetic shoulder system can include a glenoid component
attachable to the scapula and having a concave surface, and a
humeral component attachable to the humerus and having a convex
surface. Such a configuration is known as a primary
configuration.
[0005] Alternatively, the prosthetic shoulder system can include
implant components that have the opposite concavity of the natural
joint. For instance, the glenoid component can include a convex
surface, attachable to the scapula, and the humeral component can
include a concave surface, attachable to the humerus. Such a
configuration is known as a reverse configuration. The reverse
configuration can benefit patients with damaged rotator cuffs or
other muscle deterioration.
[0006] A glenoid component that can accommodate both the primary
configuration and the reverse configuration is known as a
convertible glenoid. In some examples, convertible glenoids can
provide more flexibility for a practitioner during surgery than
glenoids dedicated to primary or reverse configurations. In some
cases, a convertible glenoid can reduce a number of inventory parts
needed to perform a shoulder surgery.
[0007] Any or all of the features described in this Overview can be
used independently, or used together in any suitable combination.
This Overview is intended to provide examples of the present patent
document. It is not intended to provide an exclusive or exhaustive
explanation of the invention. The Detailed Description below is
included to provide further information about the present
convertible glenoid.
BRIEF DESCRIPTION OF THE DRAWINGS
[0008] In the drawings, which are not necessarily drawn to scale,
like numerals describe similar components in different views. The
drawings illustrate generally, by way of example, but not by way of
limitation, various embodiments discussed in the present patent
document.
[0009] FIGS. 1A-B show two views of an example of a glenoid system,
in accordance with some embodiments.
[0010] FIG. 2 shows a cross-section of the baseplate and middle peg
from FIGS. 1A-B, in accordance with some embodiments.
[0011] FIGS. 3A-B show two views of an example of a liner, in
accordance with some embodiments.
[0012] FIG. 4 shows a cross-section of the liner of FIG. 3,
attached to the baseplate of FIGS. 1A-B.
[0013] FIG. 5 shows a side view of an example of an adapter which
can attach a glenosphere or glenoid shield to a baseplate, in
accordance with some embodiments.
[0014] FIG. 6 shows a side view of another example of an adapter
which can attach a glenosphere or glenoid shield to a baseplate, in
accordance with some embodiments.
[0015] FIG. 7 shows a side view of an example of a baseplate
coupled to a middle peg, where the middle peg is configured to
attach to a middle peg extension, in accordance with some
embodiments.
[0016] FIG. 8 shows a side view of an example of a plurality of
baseplates, in accordance with some embodiments.
[0017] FIG. 9 shows a side view of an example of a glenoid system
in the primary configuration, in accordance with some
embodiments.
[0018] FIG. 10 shows a side view of an example of a glenoid system
in the reverse configuration, in accordance with some
embodiments.
[0019] FIG. 11 shows a side view of an example of a glenoid system
in a mobile bearing configuration, in accordance with some
embodiments.
[0020] FIG. 12 is a flow chart of an example of a method for
implanting a glenoid system, in accordance with some
embodiments.
DETAILED DESCRIPTION
[0021] In the following Detailed Description, the terms lateral,
medial, superior, and inferior are used to describe the relative
orientations of particular elements and features. It will be
understood that these terms are used merely for convenience, and
describe the relative orientations when the glenoid system is
surgically implanted in a shoulder of a patient. For instance, a
surface may be described herein as a lateral-facing surface,
because such a surface may face a lateral direction when the
glenoid system is implanted. One of ordinary skill in the art will
readily appreciate that the term lateral-facing surface can be used
to describe the orientation of such a surface, even when such a
surface has not been surgically implanted. As such, the terms
lateral, medial, superior, and inferior can all be considered to be
precise modifiers, which can describe elements or features that
have not, or not yet, been surgically implanted.
[0022] A glenoid system can include a metallic baseplate configured
to attach to a glenoid cavity of a patient. The baseplate can be
configured to operate in either a primary configuration (e.g., the
same concavity of the natural shoulder) or a reverse configuration
(e.g., the opposite concavity of the natural shoulder).
[0023] In the primary configuration, a biocompatibie plastic liner
can snap into a circumferential groove on the baseplate, to attach
to a lateral-facing surface of the baseplate, at one or more
locations around the groove. Attaching the plastic liner via
snapping into the circumferential groove on the baseplate can be
more effective than other attachment techniques, which can
sometimes lead to disassociation of the plastic liner,
overstuffing, or loosening of the implanted baseplate. In some
examples, using a plastic liner attached to a metal baseplate can
be more durable than using a purely plastic baseplate.
[0024] In the reverse configuration, a glenosphere or glenoid
shield can attach via taper fit to an adapter, which in turn can
attach via taper fit to the lateral-facing surface of the
baseplate. The adapter can have a lateral and/or angular offset
between the taper elements, so that the adapter can controllably
introduce lateral and/or angular offsets between the baseplate and
the glenosphere, or between the baseplate and the glenoid shield.
As such, the adapter can correct for unwanted offsets or
inclinations of the glenosphere or glenoid shield.
[0025] A middle peg can extend medially from the baseplate. An
optional middle peg extension can screw onto a medial end of the
middle peg. The middle peg extensions can be made available in
different combinations of length and material. Using a system or
kit of modular middle pegs can be smaller and less expensive than
using a comparable system or kit of glenoid baseplates that have
integral middle pegs.
[0026] The baseplates can be made available in various discrete
inferior-to-superior sizes, each of which has the same distance
between the middle peg and an interior screw hole. Using such a
system or kit can increase the spacing between the inferior and
superior screws for a particular anatomical size of the patient,
which can increase stability of the baseplate during use. Using
such a system or kit can also allow additional elements to use a
standardized spacing between the middle peg and inferior screw
hole, regardless of anatomical size.
[0027] In some examples, the glenoid baseplate can define one or
more cut-outs extending through the baseplate and shaped to
accommodate an instrument to relieve bone ongrowth or ingrowth. In
some examples, the cut-outs can be concentric with the middle peg.
The cut-outs can be used for revision surgery, and need not be used
during initial implantation.
[0028] The baseplate, circumferential groove, liner, adapter,
glenosphere, middle peg, and middle peg extension are shown in
FIGS. 1-11, and are described in detail below.
[0029] FIGS. 1A-B show two views of an example of a glenoid system
100, in accordance with some embodiments. Glenoid system 100 is but
one example of a glenoid system; other suitable glenoid systems can
also be used.
[0030] Glenoid system 100 can include a baseplate 102 that can
attach to a glenoid cavity (e.g., on the lateral face of the
scapula) of a patient. In some examples, baseplate 102 can be
formed from a biocompatible metal or a biocompatible metal alloy,
such as titanium or a cobalt-chrome alloy. In some examples, one or
more portions of the baseplate 102 that can contact bone can be
treated to improve fixation to the bone. Examples of suitable
fixation treatments can include surface blasting, hydroxyapatite
coating (HAC), plasma spray, and others.
[0031] Baseplate 102 can define a lateral-facing surface 104.
Lateral-facing surface 104 can face laterally and can extend from a
superior end 106 of the baseplate 102 to an inferior end 108 of the
baseplate 102 when the baseplate 102 is attached to the glenoid
cavity. In some examples, the lateral-facing surface 104 can be
concave. In other examples, the lateral-facing surface 104 can be
convex.
[0032] Baseplate 102 can define a superior hole 110 through the
lateral-facing surface 104 proximate the superior end 106 of the
baseplate 102. Baseplate 102 can define an inferior hole 112
through the lateral-facing surface 104 proximate the inferior end
108 of the baseplate 102. During surgery, a practitioner can screw
the baseplate 102 to the glenoid cavity, with screws that extend
through the superior hole 110 and the inferior hole 112 in the
baseplate 102. In general, it is desirable to position the superior
hole 110 and the inferior hole 112 as far apart as is practical,
which can stabilize the fixation of the baseplate 102 to the
glenoid cavity. In some examples, one or both of the superior hole
110 and inferior hole 112 are countersunk, so that when the
practitioner fully engages a screw through the respective hole, the
head of the screw lies below (e.g., medial to) the lateral-facing
surface 104. In some examples, the screw can be poly-axial.
[0033] Baseplate 102 can be coupled to a middle peg 114 at a middle
area 116 between the superior hole 110 and the inferior hole 112.
The middle peg 114 can extend medially from the baseplate 102 when
the baseplate 102 is attached to the glenoid cavity. Over time,
bone can grow on and around the middle peg 114, which can fixate
the implanted baseplate 102. In some examples, the middle peg 114
can be shaped to enhance fixation to the bone. For instance, the
middle peg 114 can have a generally cylindrical shape, with fins,
dimples, depressions, or other features that engage bone that grows
around the middle peg 114. In some examples, one or more portions
of the middle peg 114 can be treated to improve fixation to the
bone. Examples of suitable fixation treatments can include surface
blasting, hydroxyapatite coating (HAC), plasma spray, and
others.
[0034] In some examples, baseplate 102 can define a circumferential
edge 118 around the lateral-facing surface 104. In some examples,
the circumferential edge 118 can have an elongated, oval, or
pear-shaped footprint, when viewed end-on from the medial or
lateral direction. In other examples, the circumferential edge 118
can have another suitably shaped footprint.
[0035] In some examples, the circumferential edge 118 can define a
circumferential groove 120 therein. The circumferential groove 120
can be used to attach one or more additional elements to the
baseplate 102. For instance, a biocompatible plastic liner can have
one or more mating features that snap into all or a portion of the
circumferential groove 120, thereby attaching the biocompatible
plastic liner to the baseplate 102. As another example, during
surgery, the circumferential groove 120 can support removable
attachment of one or more trial components. Other suitable
components can also snap into the circumferential groove 120, as
needed.
[0036] In some examples, baseplate 102 can further include one or
more overhang elements 122. Overhang elements 122 can extend
medially from respective locations along the circumference of the
lateral-facing surface 104. Overhang elements 122 can form a lip
with the circumferential groove 120, so that once an element has
snapped into the circumferential groove 120, the overhang elements
122 block the element from being radially extended outward, out of
the circumferential groove 120. In some examples, overhang elements
122 are located at discrete locations around the circumference of
the lateral-facing surface 104, such as at four equally-spaced
locations around the circumference.
[0037] Baseplate 102 can optionally include one or more features
that are beneficial during revision surgery, e.g., surgery to
remove an implanted baseplate 102. For instance, baseplate 102 can
include one or more slots, holes, or apertures around the middle
peg 114 that allow a practitioner to insert and/or
circumferentially turn a tool around the middle peg 114 to
dissociate any bone growth from the middle peg 114.
[0038] In some examples, baseplate 102 can further define a first
slot 124 through the lateral-facing surface 104. First slot 124 can
be elongated circumferentially around the middle area 116 and
adjacent to the middle peg 114. In some examples, first slot 124
can have an inner edge coincident with a portion of an outer edge
of the middle peg 114. In some examples, first slot 124 can extend
less than halfway around the middle peg 114. In some examples,
first slot 124 can be shaped and sized to accommodate an instrument
to relieve bone ongrowth or ingrowth on the middle peg.
[0039] In some examples, baseplate 102 can further define a second
slot 126 through the lateral-facing surface 104. Second slot 126
can be elongated circumferentially around the middle area 116 and
adjacent to the middle peg 114. In some examples, second slot 126
can extend less than halfway around the middle peg 114. In some
examples, second slot 126 can be diametrically opposed to first
slot 124. In some examples, first slot 124 and second slot 126 can
be shaped and sized to accommodate an instrument to relieve bone
ongrowth or ingrowth on the middle peg 114. Slots 124, 126 are but
one example of holes or apertures that can accommodate a
bone-dissociating tool. In some examples, baseplate 102 can define
more than two slots.
[0040] The circumferential groove 120, the overhang elements 122,
the first slot 124, and the second slot 126 can all be used singly
on a baseplate 102, all together on a baseplate 102, or in any
combination with one another on a baseplate 102.
[0041] FIG. 2 shows a cross-section of the baseplate 102 and middle
peg 114 from FIGS. IA-B, in accordance with some embodiments. In
FIG. 2, the superior direction is into the plane of the page, and
the inferior direction is out of the plane of the page. FIG. 2
shows portions of the lateral-facing surface 104, the
circumferential groove 120, the first slot 124 and the second slot
126. FIG. 2 also shows a portion of the superior hole 110, disposed
behind the middle peg 114 in the view of FIG. 2.
[0042] Additionally, FIG. 2 shows a recess 228 in the middle peg
114. In some examples, the recess 228 can have a female taper 230.
In some examples, the female taper 230 can be elongated in one
direction, compared to a perpendicular direction. For instance, the
female taper 230 can be elongated along the inferior-superior
direction, compared to a direction perpendicular to the
inferior-superior direction. In other examples, the female taper
230 can be rotationally symmetric. Recess 228 can serve two
functions, related to additional elements described below.
[0043] First, for surgeries requiring the primary configuration,
the recess 228 can act as a guide for a centering feature on a
biocompatible plastic liner attachable to the baseplate 102. In
some examples, the centering feature can have an elongated
cross-section that matches the elongation of the female taper 230.
As the biocompatible plastic liner is brought into position, the
elongations can ensure that the biocompatible plastic liner is
azimuthally aligned with the baseplate 102. The recess 228 does not
form a taper fit with the centering feature. The biocompatible
plastic liner and centering feature are shown in FIGS. 3A-B and 4,
and are described in detail below.
[0044] Second, for surgeries requiring the reverse configuration,
the recess 228 can form a taper fit with an adapter, which in turn
attaches to a glenosphere or a glenoid shield via another taper
fit. The tapers on the adapter secure the adapter to the baseplate
102 and middle peg 114, and also secure the adapter to the
glenosphere or a glenoid shield. The tapers on the adapter can be
linearly and/or angularly offset with respect to one another, so
that the adapter can correct for at least one of medio-lateral
offset, supero-inferior offset, inclination, and retroversion
between the baseplate 102 and the glenosphere or glenoid shield.
The adapter is shown in FIGS. 5 and 6, and is described in detail
below.
[0045] FIGS. 3A-B show two views of an example of a liner 332, in
accordance with some embodiments. Liner 332 can be formed from a
biocompatible plastic material, such as polyethylene,
polyphenylsulfone (PPSU), polyoxymethylene (POM), and others. Liner
332 is but one example of a biocompatible plastic liner; other
suitable liners can also be used.
[0046] In some examples, liner 332 can be shaped to snap into the
circumferential groove of the baseplate and thereby attach to the
baseplate. In some examples, when the liner 332 is attached to the
baseplate, the liner 332 can fully surround a lateral end of the
baseplate, including all or a portion of a circumferential edge of
the baseplate.
[0047] In some examples, liner 332 can include a flexible raised
lip 334 around at least a portion of its circumference. The
flexible raised lip 334 can deflect radially outward, engage the
circumferential groove, and retract radially into the
circumferential groove when the liner 332 is forced against the
baseplate.
[0048] In some examples, liner 332 can include a smooth face 336
facing the baseplate, and a smooth face 338 facing away from the
baseplate. Once implanted in a patient, smooth face 338 movably
contacts a convex surface on a corresponding element attached to
the humerus, which forms the artificial shoulder joint. The convex
surface is typically metallic, so that the interface at smooth face
338 is between metal and plastic, and not between metal and
metal.
[0049] In some examples, liner 332 can include a centering feature
340. Centering feature 340 can be made integrally with the liner
332, or made separately from the liner and attached to the liner
332. The centering feature 332 can extend medially through the
baseplate, and extend medially into recess 228 (FIG. 2) of the
middle peg, when the liner 332 is attached to the baseplate. As
described above, the centering feature 340 can have an elongated
cross-section that matches the elongation of the female taper 230
(FIG. 2). As the liner 332 is brought into position, the
elongations can ensure that the liner 332 is azimuthally aligned
with the baseplate. In some examples, the centering feature 340
does not form a taper fit within the recess, and does not
mechanically support the liner 332.
[0050] FIG. 4 shows a cross-section of the liner 332 of FIG. 3,
attached to the baseplate 102 of FIGS. 1A-B. In the example of FIG.
4, the flexible raised lip 334 on the liner 332 can engage the
circumferential groove 120 on the baseplate 102. In the example of
FIG. 4, the centering feature 340 can enter into the recess 228 in
the middle peg 114, which is coupled to the baseplate 102. In the
example of FIG. 4, the centering feature 340 can have minimal or no
contact with the wall of the recess 228. In some examples, in the
event of a disassociation, this geometry can allow a series of
radiological spheres to be placed to support identification of the
liner in the joint space.
[0051] The liners of FIGS. 3 and 4 can be used in the primary
configuration singly, or in any suitable combination with any or
all of the other features discussed herein, such as the
circumferential groove 120 (FIG. 1), the overhang elements 122
(FIG. 1), the first slot 124 (FIG. 1), and the second slot 126
(FIG. 1).
[0052] FIG. 5 shows a side view of an example of an adapter 542
which can attach a glenosphere 544 to a baseplate, in accordance
with some embodiments. Adapter 542 can be formed from a
biocompatible material, such as a titanium alloy, or other suitable
biocompatible metal or a biocompatible metal alloy. FIG. 5 is but
one example of an adapter 542; other suitable adapters can also be
used.
[0053] Adapter 542 can have a first taper 546. The first taper 546
can be a male taper sized and shaped to form a taper tit with the
recess, such as recess 228 (FIG. 2) in the middle peg (FIGS. 1 and
2). The first taper 546 can be centered around a first axis
(A1).
[0054] Adapter 542 can have a second taper 548. The second taper
548 can be sized and shaped to form a taper fit with a glenosphere
or a glenoid shield. In the example of FIG. 5, the second taper 548
is a male taper, which is sized and shaped to form a taper fit with
a female taper 550 inside a recess 552 of the glenosphere 544. The
second taper 548 can be centered around a second axis (A2).
[0055] In some examples, the second axis (A2) can be linearly
offset from the first axis (A1). In some examples, the second axis
(A2) can be angularly offset from the first axis (A1). In some
examples, the second axis (A2) can be both linearly offset and
angularly offset from the first axis (A1). Such an offset can
correct for at least one of medic-lateral offset, supero-inferior
offset, inclination, and retroversion between the baseplate and the
glenosphere or glenoid shield.
[0056] FIG. 6 shows a side view of another example of an adapter
642 which can attach a glenosphere 644 to a baseplate, in
accordance with some embodiments. Compared with the example of FIG.
5, the second taper 648 and corresponding taper 650 on the
glenosphere have reversed genders. FIG. 6 is but one example of an
adapter 642; other suitable adapters can also be used.
[0057] Adapter 642 can have a first taper 646, which can be a male
taper sized and shaped to form a taper fit with the recess in the
middle peg. The first taper 646 can be centered around a first axis
(A1).
[0058] Adapter 642 can have a second taper 648. The second taper
648 can be sized and shaped to form a taper fit with a glenosphere
or a glenoid shield. In the example of FIG. 6, the second taper 648
is a female taper, which is sized and shaped to form a taper fit
with a male taper 650 on the glenosphere 644. The second taper 648
can be centered around a second axis (A2). The second axis (A2) can
be linearly and/or angularly offset from the first axis (A1).
[0059] The glenosphere 644 of FIG. 6 may be referred to as a
monoblock glenosphere. Using the adapter 642 to connect the
monoblock glenosphere to the baseplate has advantages over
connecting the monoblock glenosphere directly to the baseplate,
such as being able to correct for at least one of medio-lateral
offset, supero-inferior offset, inclination, and retroversion
between the baseplate and the glenosphere or glenoid shield.
[0060] The adapters of FIGS. 5 and 6 can be used in the reverse
configuration singly, or in any suitable combination with any or
all of the other features discussed herein, such as the
circumferential groove 120 (FIG. 1), the overhang elements 122
(FIG. 1), the first slot 124 (FIG. 1), and the second slot 126
(FIG. 1).
[0061] FIG. 7 shows a side view of an example of a baseplate 702
coupled to a middle peg 714, where the middle peg 714 is configured
to attach to a middle peg extension 752, in accordance with some
embodiments. The middle peg extension 752 can medially extend the
middle peg 714.
[0062] In some examples, the middle peg extension 752 can be formed
from biocompatible metal or a biocompatible metal alloy, such as
titanium or a cobalt-chrome alloy. In some examples, the middle peg
extension 752 can have a circular cross-section (e.g., the
cross-section, taken in a plane perpendicular to the lateral-medial
direction, can be rotationally symmetric with respect to a
lateral-medial axis). In some examples, the middle peg extension
752 can have features that can encourage bone ongrowth, such as
fins, dimples, and the like. In some examples, one or more portions
of the middle peg extension 752 can be treated to improve fixation
to the bone. Examples of suitable fixation treatments can include
surface blasting, hydroxyapatite coating (HAC), plasma spray, and
others. In some examples, Trabecular Metal can be used to enhance
fixation.
[0063] In some examples, a lateral end of the middle peg extension
752 can have male or female threads that mate with corresponding
female or male threads 754 at a medial end of the middle peg 714.
In other examples, a lateral end of the middle peg extension 752
can have a male or female taper that can form a taper fit with a
corresponding female or male taper at a medial end of the middle
peg 714.
[0064] Extending the middle peg 714 with an attachable middle peg
extension 752 can allow greater flexibility in selecting a
configuration for the area of the extension that contacts bone. For
instance, in some examples, the middle peg extension 752 can be
selected from a plurality of middle peg extensions. The plurality
of middle peg extensions can be made available as a kit, a system,
or a collection of middle peg extensions. In some examples, each
middle peg extension in the plurality can have a unique combination
of length and material. In some examples, a practitioner can select
a suitable length, from the discrete lengths available in the
plurality of middle peg extensions, to best match an anatomy of the
patient.
[0065] A threaded or taper-fit middle peg extension, such as 752,
can be used singly or in any suitable combination with any or all
of the other features discussed herein, such as the circumferential
groove 120 (FIG. 1), the overhang elements 122 (FIG. 1), the first
slot 124 (FIG. 1), the second slot 126 (FIG. 1), the centering
feature 340 extending into the recess 228 of the middle peg 114
(FIG. 4), and the adapters 542, 642 (FIGS. 5 and 6).
[0066] FIG. 8 shows a side view of an example of a plurality of
baseplates 802A-B, in accordance with some embodiments. Each
baseplate 802A-B in the plurality can have the same spacing (X)
between the middle area 818A-B and the inferior hole 812A-B. In
some examples, the spacings are denoted from a center of the
inferior holes 812A-B to a center of the middle peg 814A-B. Each
baseplate 802A-B in the plurality can having a unique spacing (Y1,
Y2) between the middle area 818A-B and the superior hole 810A-B. In
some examples, the spacings are denoted from a center of the
superior holes 810A-B to the center of the middle peg 814A-B. In
some examples, the baseplates 802A-B in the plurality can be made
available as a kit, a system, or a collection of baseplates
802A-B.
[0067] A practitioner can select a baseplate 802A-B having an
inferior-to-superior size matched to an anatomy of the patient. For
a given baseplate size, the inferior holes 812A-B and the superior
holes 810A-B can be spaced as far apart as is practical, which can
increase stability of the baseplate 802A-B when the baseplate
802A-B is attached to the glenoid cavity. In addition, the constant
spacing between the inferior holes 812A-B and the middle area
818A-B can help ensure that a glenosphere is positioned
consistently, regardless of a size of the baseplate 802A-B.
[0068] The differently-sized baseplates shown in FIG. 8 can be used
singly or in any suitable combination with any or all of the other
features discussed herein, such as the circumferential groove 120
(FIG. 1), the overhang elements 122 (FIG. 1), the first slot 124
(FIG. 1), the second slot 126 (FIG. 1), the centering feature 340
extending into the recess 228 of the middle peg 114 (FIG. 4), the
adapters 542, 642 (FIGS. 5 and 6), and the threaded or taper-fit
middle peg extension 752 (FIG. 7).
[0069] FIG. 9 shows a side view of an example of a glenoid system
900 in the primary configuration, in accordance with some
embodiments. Glenoid system 900 can include a baseplate 902, a
liner 932 configured to be snapped onto a lateral side of the
baseplate 902, a middle peg 914 extending medially from the
baseplate 902, and an optional middle peg extension 952 configured
to be screwed onto a medial end of the middle peg 914. Liner 932
can be attached using the circumferential groove 120 (FIG. 1), or
with another suitable attachment mechanism.
[0070] FIG. 10 shows a side view of an example of a glenoid system
1000 in the reverse configuration, in accordance with some
embodiments. Glenoid system 1000 can include a baseplate 1002, an
adapter 1042 configured to be attached to a lateral side of the
baseplate 1002, a glenosphere 1044 configured to be attached to a
lateral side of the adapter 1042, a middle peg 1014 extending
medially from the baseplate 1002, and an optional middle peg
extension 1052 configured to be screwed onto a medial end of the
middle peg 1014.
[0071] FIG. 11 shows a side view of an example of a glenoid system
1100 in a mobile bearing configuration, in accordance with some
embodiments. The mobile bearing configuration can have the same
concavity of the reverse configuration (FIG. 10), but using a
relatively shallow glenoid shield 1156 instead of a glenosphere.
Glenoid system 1100 can include a baseplate 1102, an adapter 1142
configured to be attached to a lateral side of the baseplate 1102,
a glenoid shield. 1156 configured to be attached to a lateral side
of the adapter 1142, a middle peg 1114 extending medially from the
baseplate 1102, and an optional middle peg extension 1152
configured to be screwed onto a medial end of the middle peg
1114.
[0072] FIG. 12 shows an example of a flow chart of a method 1200
for implanting a glenoid system, such as 100 (FIG. 1), 900 (FIG.
9), 1000 (FIG. 10), 1100 (FIG. 11). or others. The method can be
executed by a practitioner, when planning for an operation and
operating on a patient.
[0073] At operation 1202, the practitioner can select a
configuration for the implant. The configurations can include
primary or reverse. The selection can depend on the anatomy of the
patient, and the reasons for performing the shoulder replacement
surgery.
[0074] At operation 1204, the practitioner can select a
super-to-inferior baseplate size, from a plurality of discrete
sizes, which most closely matches an anatomy of the patient.
[0075] At operation 1206, the practitioner can select a length for
the middle peg, from a plurality of available peg lengths. The
available peg lengths can include a fixed length for a middle peg,
plus a plurality of discrete lengths for a middle peg
extension.
[0076] At operation 1208, the practitioner can implant a baseplate,
with the selected size, with the selected configuration, and with
the selected middle peg length.
[0077] The following non-limiting list of examples can further
illustrate the present glenoid system.
[0078] In Example 1, a glenoid system can include a baseplate
configured to attach to a glenoid cavity of a patient. The
baseplate can define a lateral-facing surface extending from a
superior end of the baseplate to an inferior end of the baseplate.
The lateral-facing surface can face laterally when the baseplate is
attached to the glenoid cavity. The baseplate can define a superior
hole through the lateral-facing surface proximate the superior end
of the baseplate. The baseplate can define an inferior hole through
the lateral-facing surface proximate the inferior end of the
baseplate. The baseplate can define a circumferential edge around
at least a portion of the lateral-facing surface. The
circumferential edge defining a circumferential groove therein.
[0079] In Example 2, the glenoid system of Example 1 can optionally
further include a biocompatible plastic liner shaped to snap into
the circumferential groove of the baseplate and thereby attach to
the baseplate, the biocompatible plastic liner at least partially
covering the lateral-facing surface of the baseplate when attached
to the baseplate.
[0080] In Example 3, the glenoid system of Example 2 can optionally
further include wherein the biocompatible plastic liner includes a
flexible raised lip around at least a portion of its circumference,
the flexible raised lip being configured to deflect radially
outward, engage the circumferential groove, and retract radially
into the circumferential groove when the biocompatible plastic
liner is forced against the baseplate.
[0081] In Example 4, the glenoid system of any one of Examples 2-3
can optionally further include wherein the biocompatible plastic
liner includes a first smooth face configured to be oriented toward
the baseplate and a second smooth face configured to be oriented
away from the baseplate.
[0082] In Example 5, the glenoid system of any one of Examples 2-4
can optionally further include wherein the biocompatible plastic
liner includes a centering feature, the centering feature extending
through the baseplate when the biocompatible plastic liner is
attached to the baseplate.
[0083] In Example 6, the glenoid system of any one of Examples 1-5
can optionally further include wherein the baseplate is coupled to
a middle peg at a middle area between the inferior and superior
holes, the middle peg extending medially from the baseplate when
the baseplate is attached to the glenoid cavity.
[0084] In Example 7, the glenoid system of Example 6 can optionally
further include wherein the centering feature is configured to
extend into a recess in the middle peg, the centering feature
forming a non-taper taper fit with the recess in the middle
peg.
[0085] In Example 8, the glenoid system of any one of Examples 6-7
can optionally further include wherein the middle peg includes a
threaded surface configured to mate with a corresponding threaded
surface on a middle peg extension.
[0086] In Example 9, the glenoid system of any one of Examples 6-7
can optionally further include wherein the middle peg includes a
taper configured to form a taper fit with a corresponding taper on
a middle peg extension.
[0087] In Example 10, the glenoid system of any one of Examples 5-9
can optionally further include wherein the centering feature has an
elongated cross-section.
[0088] In Example 11, the glenoid system of any one of Examples
1-10 can optionally further include wherein the baseplate is formed
from a biocompatible metal or a biocompatible metal alloy.
[0089] In Example 12, the glenoid system of any one of Examples
1-11 can optionally further include wherein the lateral-facing
surface is concave,
[0090] In Example 13, the glenoid system of any one of Examples 1-5
or 11-12 can optionally further include wherein the baseplate is
coupled to a middle peg at a middle area between the inferior and
superior holes, the middle peg extending medially from the
baseplate when the baseplate is attached to the glenoid cavity; and
further comprising: an adapter having a first taper, the first
taper being a male taper sized and shaped to form a taper fit with
a recess in the middle peg, the adapter further having a second
taper offset from the first taper, and the second taper being size
and shaped to form a taper fit with a glenosphere or a glenoid
shield.
[0091] In Example 14, the glenoid system of any one of Examples 1-5
or 11-12 can optionally further include wherein the baseplate is
coupled to a middle peg at a middle area between the inferior and
superior holes, the middle peg extending medially from the
baseplate when the baseplate is attached to the glenoid cavity, the
baseplate defining a first slot through the lateral-facing surface,
and the first slot being elongated circumferentially around the
middle area and adjacent to the middle peg.
[0092] In Example 15, the glenoid system of any one of Examples 1-5
or 11-12 can optionally further include wherein the baseplate is
coupled to a middle peg at a middle area between the inferior and
superior holes, the middle peg extending medially from the
baseplate when the baseplate is attached to the glenoid cavity, and
the middle peg configured to attach to a middle peg extension.
[0093] In Example 16, a glenoid system can include a baseplate
configured to attach to a glenoid cavity of a patient, the
baseplate defining a lateral-facing surface extending from a
superior end of the baseplate to an inferior end of the baseplate,
the lateral-facing surface facing laterally when the baseplate is
attached to the glenoid cavity, the baseplate defining a superior
hole through the lateral-facing surface proximate the superior end
of the baseplate, the baseplate defining an inferior hole through
the lateral-facing surface proximate the inferior end of the
baseplate, the baseplate defining a circumferential edge around at
least a portion of the lateral-facing surface, and the
circumferential edge defining a circumferential groove therein; and
a biocompatible plastic liner shaped to snap into the
circumferential groove of the baseplate and thereby attach to the
baseplate, the biocompatible plastic liner at least partially
covering the lateral-facing surface of the baseplate when attached
to the baseplate, the biocompatible plastic liner including a
flexible raised lip around at least a portion of a circumference of
the biocompatible plastic liner, the flexible raised lip being
configured to deflect radially outward, engage the circumferential
groove, and retract radially into the circumferential groove when
the biocompatible plastic liner is forced against the baseplate,
the biocompatible plastic liner including a centering feature, and
the centering feature extending through the baseplate when the
biocompatible plastic liner is attached to the baseplate.
[0094] In Example 17, the glenoid system of Example 16 can
optionally further include wherein the baseplate is coupled to a
middle peg at a middle area between the inferior and superior
holes, the middle peg extending medially from the baseplate when
the baseplate is attached to the glenoid cavity.
[0095] In Example 18, the glenoid system of any one of Examples
16-17 can optionally further include wherein the centering feature
is configured to extend into a recess in the middle peg, the
centering feature forming a non-taper taper fit with the recess in
the middle peg.
[0096] In Example 19, a glenoid system can include: a baseplate
configured to attach to a glenoid cavity of a patient, the
baseplate defining a lateral-facing surface extending from a
superior end of the baseplate to an inferior end of the baseplate,
the lateral-facing surface facing laterally when the baseplate is
attached to the glenoid cavity, the baseplate defining a superior
hole through the lateral-facing surface proximate the superior end
of the baseplate, the baseplate defining an inferior hole through
the lateral-facing surface proximate the inferior end of the
baseplate, the baseplate defining a circumferential edge around at
least a portion of the lateral-facing surface, and the
circumferential edge defining a circumferential groove therein; and
a biocompatible plastic liner shaped to snap into the
circumferential groove of the baseplate and thereby attach to the
baseplate, the biocompatible plastic liner at least partially
covering the lateral-facing surface of the baseplate when attached
to the baseplate, the biocompatible plastic liner including a
flexible raised lip around at least a portion of a circumference of
the biocompatible plastic liner, the flexible raised lip being
configured to deflect radially outward, engage the circumferential
groove, and retract radially into the circumferential groove when
the biocompatible plastic liner is forced against the baseplate,
the biocompatible plastic liner including a centering feature
having an elongated cross-section, and the centering feature
extending through the baseplate when the biocompatible plastic
liner is attached to the baseplate.
[0097] In Example 20, the glenoid system of Example 19 can
optionally further include wherein the lateral-facing surface is
concave.
[0098] The above Detailed Description includes references to the
accompanying drawings, which form a part of the Detailed
Description. The drawings show, by way of illustration, specific
embodiments in which the invention can be practiced. These
embodiments are also referred to herein as "examples." Such
examples can include elements in addition to those shown or
described. However, the inventors also contemplate examples in
which only those elements shown or described are provided.
Moreover, the inventors also contemplate examples using any
combination or permutation of those elements shown or described (or
one or more aspects thereof), either with respect to a particular
example (or one or more aspects thereof), or with respect to other
examples (or one or more aspects thereof) shown or described
herein. In this document, the terms "a" or "an" are used, as is
common in patent documents, to include one or more than one,
independent of any other instances or usages of "at least one" or
"one or more." In this document, the term "or" is used to refer to
a nonexclusive or, such that "A or B" includes "A but not B," "B
but not A," and "A and B," unless otherwise indicated. In this
document, the terms "including" and "in which" are used as the
plain-English equivalents of the respective terms "comprising" and
"wherein." Also, in the following claims, the terms "including" and
"comprising" are open-ended, that is, a system, device, kit,
article, composition, formulation, or process that includes
elements in addition to those listed after such a term in a claim
are still deemed to fall within the scope of that claim. Moreover,
in the following claims, the terms "first," "second," and "third,"
etc. are used merely as labels, and are not intended to impose
numerical requirements on their objects. The above description is
intended to be illustrative, and not restrictive. For example, the
above-described examples (or one or more aspects thereof) can be
used in combination with each other. Other embodiments can be used,
such as by one of ordinary skill in the art upon reviewing the
above description. The Abstract is provided to allow the reader to
quickly ascertain the nature of the technical disclosure. It is
submitted with the understanding that it will not be used to
interpret or limit the scope or meaning of the claims. Also, in the
above Detailed Description, various features can be grouped
together to streamline the disclosure. This should not be
interpreted as intending that an unclaimed disclosed feature is
essential to any claim. Rather, inventive subject matter can lie in
less than all features of a particular disclosed embodiment. Thus,
the following claims are hereby incorporated into the Detailed
Description as examples or embodiments, with each claim standing on
its own as a separate embodiment, and it is contemplated that such
embodiments can be combined with each other in various combinations
or permutations. The scope of the invention should be determined
with reference to the appended claims, along with the full scope of
equivalents to which such claims are entitled.
* * * * *