U.S. patent application number 15/938454 was filed with the patent office on 2018-08-02 for femoral stem including an anchor to facilitate assembly and implantation.
The applicant listed for this patent is DEPUY SYNTHES PRODUCTS, INC.. Invention is credited to Theodore L. BADGLEY, Justin D. GROSTEFON, Edward KAVANAUGH, Jeffrey A. MCANELLY, Jeffrey R. ROOSE, Rodney E. SATTERTHWAITE.
Application Number | 20180214275 15/938454 |
Document ID | / |
Family ID | 55305074 |
Filed Date | 2018-08-02 |
United States Patent
Application |
20180214275 |
Kind Code |
A1 |
GROSTEFON; Justin D. ; et
al. |
August 2, 2018 |
FEMORAL STEM INCLUDING AN ANCHOR TO FACILITATE ASSEMBLY AND
IMPLANTATION
Abstract
An orthopaedic prosthesis for use in a hip replacement surgery.
The orthopaedic prosthesis includes an elongated stem component
that has a proximal body, a neck extending superiorly and medially
from the proximal body and a tapered stem extending inferiorly from
the proximal body. An anchor is positioned on the neck and is
configured to be engaged by a surgical instrument. A system for use
in assembling the orthopaedic prosthesis and a method of assembly
are also disclosed.
Inventors: |
GROSTEFON; Justin D.;
(Columbia City, IN) ; SATTERTHWAITE; Rodney E.;
(Huntington, IN) ; MCANELLY; Jeffrey A.; (Columbia
City, IN) ; ROOSE; Jeffrey R.; (Milford, IN) ;
KAVANAUGH; Edward; (Warsaw, IN) ; BADGLEY; Theodore
L.; (Fort Wayne, IN) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
DEPUY SYNTHES PRODUCTS, INC. |
RAYNHAM |
MA |
US |
|
|
Family ID: |
55305074 |
Appl. No.: |
15/938454 |
Filed: |
March 28, 2018 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
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14995518 |
Jan 14, 2016 |
9937048 |
|
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15938454 |
|
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62103826 |
Jan 15, 2015 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
A61F 2002/365 20130101;
A61F 2002/30879 20130101; A61F 2002/3627 20130101; A61F 2002/3625
20130101; A61F 2/3609 20130101; A61F 2002/3654 20130101; A61F 2/367
20130101; A61F 2002/30332 20130101; A61F 2/3607 20130101; A61F
2002/3631 20130101; A61F 2002/4627 20130101; A61F 2002/4666
20130101; A61F 2002/368 20130101; A61F 2002/30772 20130101; A61F
2/4637 20130101 |
International
Class: |
A61F 2/36 20060101
A61F002/36; A61F 2/46 20060101 A61F002/46 |
Claims
1. An orthopaedic prosthesis, comprising: an elongated stem
component, comprising: (i) a proximal body, (ii) a neck extending
superiorly and medially from the proximal body, the neck having a
longitudinal axis and being configured to receive a femoral head
component, (iii) a tapered stem extending inferiorly from the
proximal body, and (iv) an anchor positioned on the neck, wherein
the anchor extends orthogonal to the longitudinal axis of the neck.
Description
[0001] This application claims priority under 35 U.S.C. .sctn.119
to U.S. Patent App. Ser. No. 62/103,826 entitled "FEMORAL STEM
INCLUDING AN ANCHOR TO FACILITATE ASSEMBLY AND IMPLANTATION," which
was filed Jan. 15, 2015, and U.S. patent application Ser. No.
14/995,518 entitled "FEMORAL STEM INCLUDING AN ANCHOR TO FACILITATE
ASSEMBLY AND IMPLANTATION," which was filed Jan. 14, 2016, both of
which are expressly incorporated herein by reference.
CROSS-REFERENCE
[0002] Cross-reference is made to U.S. Patent App. Ser. No.
62/103,611 entitled "ASSEMBLY TOOL," which was filed Jan. 15, 2015
and is expressly incorporated herein by reference.
TECHNICAL FIELD
[0003] The present disclosure relates generally to orthopaedic
prostheses, and particularly to orthopaedic prostheses for use in
hip replacement surgery.
BACKGROUND
[0004] Joint arthroplasty is a well-known surgical procedure by
which a diseased and/or damaged natural joint is replaced by a
prosthetic joint. The prosthetic joint may include a prosthesis
that is implanted into one or more of the patient's bones. Many hip
prostheses include a femoral prosthesis that is implanted into a
patient's femur. A femoral prosthesis typically includes an
elongated stem component that is received in the medullary canal of
the patient's femur and a spherically-shaped head component that
bears against the patient's acetabulum or a prosthetic replacement
acetabular cup.
[0005] The elongated stem implant may be cemented into the
medullary canal or may have a porous coated surface for allowing
the bone to heal directly to the implant. In some prostheses, the
head is attached to a neck of the elongated stem via a taper
connection. It is important to assemble the head to the neck with
enough force so as to limit micromotion between the head and neck.
The acetabulum of the patient may also be reamed to receive a shell
and liner. A polyethylene, metal or ceramic liner with a metal
shell is inserted into the acetabulum and acts as socket for
receiving the head on the stemmed implant.
SUMMARY
[0006] According to one aspect of the disclosure, an orthopaedic
prosthesis is disclosed. The orthopaedic prosthesis comprises an
elongated stem component. The elongated stem component includes a
proximal body and a neck extending superiorly and medially from the
proximal body. The neck has a longitudinal axis and is configured
to receive a femoral head component. The stem component also
includes a tapered stem extending inferiorly from the proximal
body, and an anchor positioned on the neck. The anchor extends
orthogonal to the longitudinal axis of the neck.
[0007] In some embodiments, the anchor may include a first flange
positioned on an anterior side of the neck and a second flange
positioned on a posterior side of the neck. In some embodiments,
the first flange may extend outwardly from the anterior side of the
neck, and the second flange may extend outwardly from the posterior
side of the neck. Additionally, in some embodiments, a first
opening may be defined in the anterior side of the neck, and the
first flange may include a first inner wall extending inwardly from
the first opening.
[0008] In some embodiments, a second opening may be defined in the
posterior side of the neck, and the second flange may include a
second inner wall extending inwardly from the second opening.
[0009] In some embodiments, the first flange and the second flange
may include engagement surfaces that are positioned in an imaginary
plane extending orthogonal to the longitudinal axis of the
neck.
[0010] In some embodiments, the neck may include a first opening
defined in an anterior surface, a second opening defined in a
posterior surface, and the anchor may include an inner wall that
extends between the first opening and the second opening.
[0011] In some embodiments, the inner wall may include a
substantially planar medial surface and a curved surface connected
to the substantially planar medial surface. Additionally, in some
embodiments, the neck may extend from a superior tip to an inferior
end attached to the proximal body, and the anchor may be positioned
on the medial side of the inferior end of the neck.
[0012] In some embodiments, the anchor may include a medial collar
extending outwardly from the inferior end of the neck. In some
embodiments, an opening may be defined in the inferior end of the
neck, and the anchor may include an inner wall that extends
inwardly from the opening.
[0013] In some embodiments, the proximal body may have a first
opening defined in an anterior side and a second opening defined in
a posterior side adjacent to the neck. The neck may include a first
inner wall that extends inwardly from the first opening and a
second inner wall that extends inwardly from the second opening.
The anchor may include the first inner wall and the second inner
wall.
[0014] In some embodiments, the orthopaedic prosthesis may include
the femoral head component including a tapered bore. The neck may
include a tapered trunnion sized to receive the tapered bore.
[0015] According to another aspect, a system for hip orthopaedic
surgery is disclosed. The system includes a femoral head component,
an elongated stem component, and a surgical instrument. The
elongated stem component includes a proximal body, a neck extending
superiorly and medially from the proximal body, a tapered stem
extending inferiorly from the proximal body, and an anchor
positioned on the neck and extending orthogonal to the longitudinal
axis of the neck. The neck is configured to receive the femoral
head component.
[0016] The surgical instrument includes a plate configured to
engage the femoral head component, an arm configured to engage the
anchor to secure the surgical instrument to the elongated stem
component, and an actuator configured to move the plate along an
axis to apply a force to the femoral head component.
[0017] In some embodiments, the anchor may include a first flange
positioned on an anterior side of the neck and a second flange
positioned on a posterior side of the neck. The arm of the surgical
instrument may be a first arm configured to engage the first
flange, and the surgical instrument may include a second arm
configured to engage the second flange.
[0018] In some embodiments, the proximal body may have a first
opening defined in an anterior side and a second opening defined in
a posterior side adjacent to the neck. The neck may include a first
inner wall that extends inwardly from the first opening and a
second inner wall that extends inwardly from the second opening.
The anchor may include the first inner wall and the second inner
wall.
[0019] According to another aspect, an orthopaedic prosthesis
comprises a femoral head component and an elongated stem component.
The elongated stem component comprises a proximal body, a neck that
is configured to receive the femoral head component and extending
superiorly and medially from the proximal body, and a tapered stem
extending inferiorly from the proximal body. A first opening is
defined an anterior surface of the neck, a second opening is
defined in a posterior surface of the neck, and a pair of inner
walls extend inwardly from the first opening and the second
opening. Each inner wall includes a medial surface positioned in an
imaginary plane extending orthogonal to the longitudinal axis of
the neck.
[0020] In some embodiments, the pair of inner walls may define a
single inner wall extending from the first opening between the
second opening.
BRIEF DESCRIPTION OF THE DRAWINGS
[0021] The detailed description particularly refers to the
following figures, in which:
[0022] FIG. 1 is a perspective view of an orthopaedic implant;
[0023] FIG. 2A is an anterior side elevation view of the
orthopaedic implant of FIG. 1;
[0024] FIG. 2B is a posterior side elevation view of the
orthopaedic implant of FIG. 1;
[0025] FIG. 3 is a perspective view of a surgical instrument for
use with the orthopaedic implant of FIG. 1;
[0026] FIGS. 4-6 are views of a process of implanting the
orthopaedic implant of FIG. 1 using the surgical instrument of FIG.
3;
[0027] FIG. 7 is a side elevation view of another embodiment of an
orthopaedic implant;
[0028] FIG. 8 is an opposite side elevation view of the embodiment
of FIG. 7;
[0029] FIG. 9 is a perspective view of another embodiment of an
orthopaedic implant;
[0030] FIG. 10 is a perspective view of another embodiment of an
orthopaedic implant;
[0031] FIG. 11 is a first side perspective view of another
embodiment of an orthopaedic implant;
[0032] FIG. 12 is a second side perspective view of the embodiment
of FIG. 11; and
[0033] FIG. 13 is a perspective view of another embodiment of an
orthopaedic implant.
DETAILED DESCRIPTION OF THE DRAWINGS
[0034] While the concepts of the present disclosure are susceptible
to various modifications and alternative forms, specific exemplary
embodiments thereof have been shown by way of example in the
drawings and will herein be described 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 falling within the spirit and scope
of the invention as defined by the appended claims.
[0035] Terms representing anatomical references, such as anterior,
posterior, medial, lateral, superior, inferior, etcetera, may be
used throughout the specification in reference to the orthopaedic
implants or prostheses and surgical instruments described herein as
well as in reference to the patient's natural anatomy. Such terms
have well-understood meanings in both the study of anatomy and the
field of orthopaedics. Use of such anatomical reference terms in
the written description and claims is intended to be consistent
with their well-understood meanings unless noted otherwise.
[0036] Referring to FIG. 1, an orthopaedic prosthesis is
illustratively embodied as a femoral orthopaedic implant 10 of a
hip prosthesis. The femoral orthopaedic implant 10 (hereinafter
implant 10) includes a head component 12 and an elongated stem
component 14 that is configured to be inserted into an
intramedullary canal 16 of a patient's surgically-prepared femur
18. In particular, the femoral stem component 14 is implanted into
a surgically prepared (e.g., broached) intramedullary canal 16 of
the patient's femur 18.
[0037] The head component 12 includes a spherical outer surface 20
configured to engage a patient's natural acetabulum (not shown) or
a prosthetic acetabular cup implanted into the patient's pelvic
bone. The head component 12 may be constructed with an
implant-grade biocompatible metal, although other materials may
also be used. Examples of such metals include cobalt, including
cobalt alloys such as a cobalt chrome alloy, titanium, including
titanium alloys such as a Ti6Al4V alloy, and stainless steel. The
head component 12 also includes a distal surface 22 having an
opening 24 defined therein, and an inner wall extends inwardly from
the opening 24 to define a tapered bore 28 in the head component
12.
[0038] The head component 12 is secured to a trunnion 30 formed in
the end 32 of the elongated neck 34 of the stem component 14. As
shown in FIG. 1, the elongated neck 34 has a longitudinal axis 36
that extends through the trunnion 30. In the illustrative
embodiment, the head component 12 is advanced along the
longitudinal axis 36 to advance the tapered trunnion 30 of the stem
component 14 may be advanced into the tapered bore 28 of the head
component 12 to taper lock the trunnion 30 (and hence the stem
component 14) and the femoral head component 12 to one another.
When installed on the stem component 14, the femoral head component
12 is positioned to bear on either the patient's natural acetabulum
or a prosthetic socket which has been implanted into the patient's
pelvis to replace his or her acetabulum. In such a manner, the
orthopaedic hip prosthesis 10 and the natural or artificial
acetabulum collectively function as a system which replaces the
natural joint of the patient's hip
[0039] As shown in FIG. 1, the elongated neck 34 extends medially
and superiorly from an inferior end 38 attached to a proximal body
40 of the elongated stem component 14. As described in greater
detail below, the elongated stem component 14 also includes a tool
engagement feature or anchor 42 that is positioned on the neck 34.
A tapered stem 44 extends inferiorly away from the opposite end of
the proximal body. The tapered stem 44 has a rounded distal end 46
that defines the inferior-most surface of the femoral stem
component 14.
[0040] In the illustrative embodiment described herein, the stem
component 14 is embodied as a "fit and fill" type of femoral stem.
As such, the stem component 14 is embodied as a monolithic metal
structure. The stem component 14 may be constructed with an
implant-grade biocompatible metal, although other materials may
also be used. Examples of such metals include cobalt, including
cobalt alloys such as a cobalt chrome alloy, titanium, including
titanium alloys such as a Ti6Al4V alloy, and stainless steel. Such
a metallic femoral stem component 14 may also be coated with a
surface treatment, such as hydroxyapatite, to enhance
biocompatibility. Moreover, the surfaces of the femoral stem
component 14 that engage the natural bone, such as the outer
surface of the proximal body 40, may be textured to facilitate
securing the component to the bone. Such surfaces may also be
porous coated to promote bone ingrowth for permanent fixation.
[0041] As shown in FIGS. 2A and 2B, the anchor 42 of the elongated
stem component 14 is defined in an anterior surface 50 and a
posterior surface 54. The anterior surface 50 of the stem component
14 extends from the inferior end 38 of the neck 34 to the base of
the trunnion 30, and an opening 52 is defined in the anterior
surface 50 adjacent to the inferior end 38 of the neck 34. The
posterior surface 54 extends from the inferior end 38 of the neck
34 to the base of the trunnion 30. Another opening 56 is defined in
the posterior surface 54 adjacent to the inferior end 38 of the
neck 34. In the illustrative embodiment, the anchor 42 includes an
inner wall 60 that extends inwardly from the openings 52, 56. As
shown in FIGS. 2A and 2B, the inner wall 60 defines a passageway 62
through the elongated neck 34.
[0042] The inner wall 60 includes a medial surface 64 and a curved
lateral surface 66 that extend between the openings 52, 56. In the
illustrative embodiment, the medial surface 64 is substantially
planar and extends orthogonal to the longitudinal axis 36 of the
elongated neck 34. In other embodiments, the medial surface 64 (and
hence the anchor 42) may merely extend transverse to the axis 36.
Additionally, as shown in FIGS. 2A and 2B, the medial surface 64
extends between a superior edge 68 and an inferior edge 70 that are
connected to the lateral surface 66. In the illustrative
embodiment, the longitudinal axis 36 intersects the medial surface
64 at a midpoint 72 on the surface 64 between the edges 68, 70. It
should be appreciated that in other embodiments the axis 36 may be
offset from the midpoint 72.
[0043] Referring now to FIG. 3, a surgical instrument 100 for use
in securing the femoral head component 12 to the elongated stem
component 14 is shown. The surgical instrument 100 includes a body
102, an actuator 104 configured to engage the femoral head
component 12, and a pair of elongated arms 106 configured to engage
the anchor 42 of the elongated stem component 14. The body 102 of
the instrument 100 includes an elongated bore 108 that extends from
a distal end 110 to a proximal end 112. In the illustrative
embodiment, the elongated bore 108 is internally-threaded at the
distal end 110.
[0044] The actuator 104 of the instrument 100 has a shaft 114 that
extends through the elongated bore 108 and an engagement plate 116
that is attached to the distal end 118 of the shaft 114. The distal
end 118 of the shaft 114 includes a plurality of external threads
120 that are configured to engage the internally-threaded bore 108
of the body 102. A handle 122 is secured to the shaft 114 at the
end opposite the distal end 118. As described in greater detail
below, the handle 122 is operable to rotate the shaft 114 and move
the engagement plate 116 along an axis 124 defined by the shaft
114.
[0045] As shown in FIG. 3, the engagement plate 116 includes a base
126 that is secured to the distal end 118 of the shaft 114. The
plate 116 also includes a distal surface 128 that is configured to
engage the femoral head component 12. In the illustrative
embodiment, the distal surface 128 is concave to define a recess
130 that receive the spherical outer surface 20 of the femoral head
component 12. The engagement plate 116 is illustratively formed
from a polymeric material such as a hard plastic. It should be
appreciated that in other embodiments the plate 116 may be
partially or fully formed from a metallic material. In other
embodiments, the plate 116 may also include a gasket formed from an
elastomeric material, which is configured to engage the head
component 12.
[0046] As described above, the instrument 100 also includes a pair
of elongated arms 106 configured to engage the anchor 42 of the
elongated stem component 14. Each arm 106 includes an elongated
body 132 that extends from a distal end 134 to a proximal end 136.
An engagement pin 138 extends outwardly from the distal end 134 of
each arm 106 in a direction perpendicular or orthogonal to the axis
124 defined by the actuator 104. As shown in FIG. 3, the engagement
pins 138 are shaped to be received in the passageway 62 defined in
the elongated stem component 14.
[0047] The elongated arms 106 are coupled to the body 102 of the
instrument 100 such that the arms 106 (and hence the engagement
pins 138) may be repositioned relative to the axis 124. In the
illustrative embodiment, the body 102 has a pair of channels 140
defined therein on each side of the elongated bore 108. Each
channel 140 is sized to receive a corresponding proximal end 136 of
one of the arm bodies 132. It should be appreciated that in other
embodiments the instrument may include other combinations of tabs,
openings, channels, or passageways to attach the arms to the
body.
[0048] The instrument 100 also includes an adjustment mechanism 142
configured to permit the arms 106 to be selectively moved relative
to the body 102 (and hence the axis 124). In the illustrative
embodiment, the adjustment mechanism 142 includes a pair of screw
clamps 144, 146 that may be operated by the user to independently
position and fix each of the arms 106 at a desired position
relative to the axis 124. It should be appreciated that in other
embodiments the adjustment mechanism may include other fasteners,
screws, tabs, and so forth configured to permit the arms to be
selectively moved.
[0049] During a surgical procedure, the elongated stem component 14
may be inserted into a surgically-prepared intramedullary canal 16
of a patient's femur 18, as shown in FIG. 4. To attach a femoral
head component 12, the surgeon may align the selected head
component 12 with the trunnion 30 of the elongated stem component
14. The surgeon may advance the head component 12 along the
longitudinal axis 36 such that the trunnion 30 is received in the
tapered bore 28 defined in the head component 12.
[0050] A user, such as a surgeon or a surgical assistant, may then
use the surgical instrument 100 to apply controllably a sufficient,
quasistatic axial force to join the head component 12 to the stem
component 14. A quasistatic axial force as used herein refers to an
axial force that is applied gradually, increasing from a low to a
high, peak magnitude. Conversely, a quasidynamic axial force as
used herein refers to a high axial force that is applied, more or
less, instantaneously, such as like a hammer strike.
[0051] To attach the surgical instrument 100, the user may operate
the screw clamps 144, 146 to disengage the clamps 144, 146 from the
proximal ends 136 of the elongated arms 106, thereby releasing the
arms 106 for movement relative to the axis 124. The user may then
pull the arms 106 away from the axis 124, which moves the
engagement pins 138 apart. The engagement plate 116 may be advanced
into the contact with the spherical outer surface 20 of the femoral
head component 12, and the axis 124 aligned with the longitudinal
axis 36 of the elongated neck 34 of the stem component 14.
[0052] As shown in FIG. 6, the engagement pins 138 may be aligned
with the passageway 62 defined in the stem component 14. The user
may then advance the pins 138 into the passageway 62. When the pins
138 are positioned at the desired location, the user may operate
the clamps 144, 146 to lock the elongated arms 106 (and hence the
pins 138) into position. With the instrument 100 positioned as
shown in FIG. 6, the user may rotate the handle 122 to advance the
head component 12 along the aligned axes 36, 124 in the direction
indicated by arrow 150. To exert the quasistatic axial force on the
components 12, 14, the engagement pins 138 of the instrument 100
engage the medial surface 64 of the anchor 42 of the stem component
14 such that the actuator 104 applies a force to the components 12,
14 along the axes 36, 124 when the handle 122 is rotated.
[0053] In the illustrative embodiment, the instrument 100 is
configured to apply at least a peak axial force of about 4 kN. It
should be appreciated that in other embodiments the instrument may
include a force gauge or other sensor to measure the force applied
to the components 12, 14. After the user has applied a desired
amount of force to secure the head component 12 to the stem
component 14, the user may reverse actuator the instrument 100 and
remove the instrument from the surgical area.
[0054] While the instrument 100 is illustrative hand-operated, it
should be appreciated that in other embodiments the instrument 100
may include a motor or other drive mechanism to apply the axial
force. Other surgical instruments configured to apply a quasistatic
axial force are disclosed in co-pending U.S. Patent Application
Ser. No. 62/103,611 entitled "ASSEMBLY TOOL," which is filed
concurrently with this application. Such surgical instruments may
be configured for use with specific, compatible types of anchors
but may be adapted for use with the anchor 42 of the stem component
14. In other embodiments, the stem component may include other
anchor configurations similar to those illustrated in FIGS. 7-13,
which are described in greater detail below. Some features of the
embodiments illustrated in FIGS. 7-13 are substantially similar to
those discussed above in reference to the embodiment of FIGS. 1-6.
Such features are designated in FIGS. 7-13 with the same reference
numbers as those used in FIGS. 1-6.
[0055] Referring now to FIGS. 7-8, another elongated stem component
(hereinafter stem component 214) is shown. Similar to the
embodiment of FIGS. 1-6, the stem component 214 includes a trunnion
30 formed in the end 32 of the elongated neck 234 of the stem
component 214. The elongated neck 234 also has a longitudinal axis
36 that extends through the trunnion 30. As shown in FIG. 7, the
elongated neck 234 extends medially and superiorly from an inferior
end 38 attached to a proximal body 240 of the elongated stem
component 214. Similar to the embodiment of FIGS. 1-6, a tapered
stem (not shown) extends inferiorly away from the opposite end of
the proximal body.
[0056] The elongated stem component 214 also includes a tool
engagement feature or anchor 242 that is positioned on the neck
234. The anchor 242 of the elongated stem component 214 is defined
in an anterior surface 250 and a posterior surface 254. The
anterior surface 250 of the stem component 214 extends from the
inferior end 38 of the neck 234 to the base of the trunnion 30, and
an opening 252 is defined in the anterior surface 250 adjacent to
the inferior end 38 of the neck 234. The posterior surface 254
extends from the inferior end 38 of the neck 234 to the base of the
trunnion 30. Another opening 256 is defined in the posterior
surface 250 adjacent to the inferior end 38 of the neck 34. In the
illustrative embodiment, the anchor 242 includes an inner wall 258
that extends inwardly from the opening 252 and another inner wall
260 that extends inwardly from the opening 256.
[0057] As shown in FIGS. 7-8, the inner wall 258 is one of a
plurality of inner walls 262 that extend from the opening 252 to a
base surface 264. The base surface 264 and the inner walls 262
cooperate to define a closed aperture 266 in the anterior surface
250. Similarly, the inner wall 260 is one of a plurality of inner
walls 270 that extend from the opening 256 to a base surface 272.
The base surface 272 and the inner walls 270 cooperate to define a
closed aperture 274 in the posterior surface 254. In the
illustrated embodiment, the apertures 266, 274 are square-shaped.
In other embodiments, the apertures may be rectangular, circular or
other geometric shape.
[0058] In the illustrative embodiment, the inner walls 258, 260
include medial surfaces 278 that are substantially planar and are
positioned in a common imaginary plane that extends through the
elongated neck 234 orthogonal to the longitudinal axis 36. In other
words, the medial surfaces 278, like the medial surface 64 of the
stem component 14, extend orthogonal relative to the axis 36.
[0059] The anchor 242 of the stem component 214 may be engaged by
an appropriately-shaped surgical instrument in a manner similar to
that described above in regard to FIGS. 1-6. For example, the
engagement pins 138 of the surgical instrument 100 may be shaped to
be received in the closed apertures 266, 274 of the stem component
214 and thereby engage the anchor 242. In other embodiments, other
surgical instruments may be used.
[0060] Referring now to FIG. 9, another embodiment of an elongated
stem component (hereinafter stem component 314) is shown. Similar
to the embodiments of FIGS. 1-8, the stem component 314 includes a
trunnion 30 formed in the end 32 of the elongated neck 334 of the
stem component 314. The elongated neck 334 also has a longitudinal
axis 36 that extends through the trunnion 30. As shown in FIG. 9,
the elongated neck 334 extends medially and superiorly from an
inferior end 38 attached to a proximal body 340 of the elongated
stem component 314. A tapered stem (not shown) extends inferiorly
away from the opposite end of the proximal body.
[0061] The elongated stem component 314 also includes a tool
engagement feature or anchor 342 that is positioned on the neck
334. In the illustrative embodiment, the neck 334 has an opening
344 defined in a medial surface 346 at its inferior end 38. A
number of inner walls 348 extend inwardly from the opening 344 to
base surface 350. A closed pocket 352 is defined by the surfaces
350 and the inner walls 348. In the illustrated embodiment, the
closed pocket 352 is rectangular-shaped. In other embodiments, the
apertures may be square, circular or other geometric shape.
[0062] The anchor 342 includes a superior surface 354 of one of the
inner walls 348. The superior surface 354 extends orthogonal to the
longitudinal axis 36. In other embodiments, the surface 354 (and
hence the anchor 342) may merely extend transverse to the axis 36.
The superior surface 354 may be engaged by an appropriately-shaped
surgical instrument in a manner similar to that described above in
regard to FIGS. 1-8. For example, the surgical instrument 100 may
be configured with only a single engagement pin 138 that is shaped
to be received in the closed pocket 352 of the stem component 314
and thereby engage the superior surface 354 of the anchor 342. In
other embodiments, other surgical instruments may be used.
[0063] Referring now to FIG. 10, another embodiment of an elongated
stem component (hereinafter stem component 414) is shown. Similar
to the embodiments of FIGS. 1-8, the stem component 414 includes a
trunnion 30 formed in the end 32 of the elongated neck 434 of the
stem component 414. The elongated neck 434 also has a longitudinal
axis 36 that extends through the trunnion 30. As shown in FIG. 10,
the elongated neck 434 extends medially and superiorly from an
inferior end 38 attached to a proximal body 440 of the elongated
stem component 414. A tapered stem (not shown) extends inferiorly
away from the opposite end of the proximal body.
[0064] The elongated stem component 414 also includes a tool
engagement feature or anchor 442 that is positioned on the neck
434. In the illustrative embodiment, the neck 434 has a collar 444
that extends outwardly from a medial surface 446 at its inferior
end 38. As shown in FIG. 10, the collar 444 has a slot 448
extending from a superior opening 450 to an inferior opening (not
shown) and a curved outer surface 452. The slot 448 is sized to
receive an appropriately sized surgical instrument. In other
embodiments, the slot may be omitted.
[0065] The collar 444 extends orthogonal to the longitudinal axis
36, and may be engaged by an appropriately-shaped surgical
instrument in a manner similar to that described above in regard to
FIGS. 1-9. For example, the surgical instrument 100 may be
configured with only a single engagement pin 138 that is shaped to
engage the collar 444 of the anchor 442. In other embodiments,
other surgical instruments may be used.
[0066] Referring now to FIGS. 11-12, another elongated stem
component (hereinafter stem component 514) is shown. Similar to the
embodiments of FIGS. 1-10, the stem component 514 includes a
trunnion 30 formed in the end 32 of the elongated neck 534 of the
stem component 214. The elongated neck 534 also has a longitudinal
axis 36 that extends through the trunnion 30. As shown in FIG. 11,
the elongated neck 534 extends medially and superiorly from an
inferior end 38 attached to a proximal body 540 of the elongated
stem component 514. A tapered stem (not shown) extends inferiorly
away from the opposite end of the proximal body.
[0067] The elongated stem component 514 also includes a tool
engagement feature or anchor 542 that is positioned on the neck
534. The anchor 542 of the elongated stem component 514 includes a
pair of flanges 544, 546 that extend outwardly from an anterior
surface 550 and a posterior surface 554, respectively. As shown in
FIG. 11, the anterior surface 550 of the stem component 514 extends
from the inferior end 38 of the neck 534 to the base of the
trunnion 30, and the flange 544 extends outwardly from the surface
550 adjacent to the inferior end 38 of the neck 534. The flange 544
includes an elongated body 556 that extends orthogonal to the axis
36. The flange 544 also includes a superior surface 558 and an
inferior surface 560.
[0068] As shown in FIG. 12, the posterior surface 554 extends from
the inferior end 38 of the neck 534 to the base of the trunnion 30.
The flange 546 extends outwardly from the surface 554 adjacent to
the inferior end 38 of the neck 534. The flange 546 includes an
elongated body 566 that extends orthogonal to the axis 36. The
flange 546 also includes a superior surface 568 and an inferior
surface 570.
[0069] In the illustrative embodiment, the inferior surfaces 560,
570 are substantially planar and are positioned in a common
imaginary plane that extends through the elongated neck 534
orthogonal to the longitudinal axis 36. In other words, the
inferior surfaces 560, 570, like the medial surface 64 of the stem
component 14, extend orthogonal relative to the axis 36.
[0070] The anchor 542 (i.e., the flanges 544, 546) of the stem
component 514 may be engaged by an appropriately-shaped surgical
instrument in a manner similar to that described above in regard to
FIGS. 1-10. For example, the engagement pins 138 of the surgical
instrument 100 may be shaped to engage the flanges 544, 546. In
other embodiments, other surgical instruments may be used.
[0071] Referring now to FIG. 13, another elongated stem component
(hereinafter stem component 614) is shown. Similar to the
embodiments of FIGS. 1-12, the stem component 614 includes a
trunnion 30 formed in the end 32 of the elongated neck 634 of the
stem component 614. The elongated neck 634 also has a longitudinal
axis 36 that extends through the trunnion 30. As shown in FIG. 11,
the elongated neck 234 extends medially and superiorly from an
inferior end 638 attached to a proximal body 640 of the elongated
stem component 214. A tapered stem 644 extends inferiorly away from
the opposite end of the proximal body 640 to a distal end 646.
[0072] The elongated stem component 614 also includes a tool
engagement feature or anchor 642. In the illustrative embodiment,
the anterior surface 650 of the proximal body 640 has an opening
652 defined therein. An inner wall 654 extends inwardly from the
opening 652 to define a closed aperture 656 in the body 640. As
shown in FIG. 13, the aperture 656 has an open end 658 that is
closed by an inferior surface 660 of the elongated neck 634.
[0073] The anchor 642 includes the inferior surface 660. The anchor
642 also includes another inferior surface (not shown) defined on
the posterior side 662 of the stem component 614. In the
illustrative embodiment, the inferior surfaces 660 are
substantially planar and are positioned in a common imaginary plane
that extends through the elongated neck 634 orthogonal to the
longitudinal axis 36.
[0074] The anchor 642 of the stem component 614 may be engaged by
an appropriately-shaped surgical instrument in a manner similar to
that described above in regard to FIGS. 1-6. For example, the
engagement pins 138 of the surgical instrument 100 may be shaped to
be received in the closed apertures 656 of the stem component 614
and thereby engage the anchor 642. In other embodiments, other
surgical instruments may be used.
[0075] It should be appreciated that the anchors of the stem
components described above may be configured for use in other parts
of the orthopaedic surgical procedure. For example, a surgeon may
use the anchors to grip the stem during implantation and
extraction, thereby eliminating the need for a separate feature to
perform that step.
[0076] While the disclosure has been illustrated and described in
detail in the drawings and foregoing description, such an
illustration and description is to be considered as exemplary and
not restrictive in character, it being understood that only
illustrative embodiments have been shown and described and that all
changes and modifications that come within the spirit of the
disclosure are desired to be protected.
[0077] There are a plurality of advantages of the present
disclosure arising from the various features of the method,
apparatus, and system described herein. It will be noted that
alternative embodiments of the method, apparatus, and system of the
present disclosure may not include all of the features described
yet still benefit from at least some of the advantages of such
features. Those of ordinary skill in the art may readily devise
their own implementations of the method, apparatus, and system that
incorporate one or more of the features of the present invention
and fall within the spirit and scope of the present disclosure as
defined by the appended claims.
* * * * *