U.S. patent application number 14/185193 was filed with the patent office on 2015-08-20 for spinal fixation device.
The applicant listed for this patent is K2M, Inc.. Invention is credited to Michael Barrus.
Application Number | 20150230828 14/185193 |
Document ID | / |
Family ID | 52477635 |
Filed Date | 2015-08-20 |
United States Patent
Application |
20150230828 |
Kind Code |
A1 |
Barrus; Michael |
August 20, 2015 |
SPINAL FIXATION DEVICE
Abstract
A spinal fixation device is provided. The spinal fixation device
includes a body portion including a stud portion defining a first
annular groove. An outer housing is positionable on the stud
portion of the body portion. An inner housing defines a second
annular groove and is positionable between the outer housing and
the stud portion. A ring member is positionable within each of the
first and second annular grooves of the respective stud portion and
inner housing to lock the inner housing to the body portion and to
fixedly couple the outer housing to the stud portion.
Inventors: |
Barrus; Michael; (Ashburn,
VA) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
K2M, Inc. |
Leesburg |
VA |
US |
|
|
Family ID: |
52477635 |
Appl. No.: |
14/185193 |
Filed: |
February 20, 2014 |
Current U.S.
Class: |
606/276 ;
606/279 |
Current CPC
Class: |
A61B 17/7032 20130101;
A61B 17/705 20130101; A61B 17/7056 20130101 |
International
Class: |
A61B 17/70 20060101
A61B017/70 |
Claims
1. A spinal fixation device, comprising: a body portion including a
stud portion defining a first annular groove; an outer housing
positionable on the stud portion; an inner housing defining a
second annular groove, the inner housing positionable between the
outer housing and the stud portion; and a ring member positionable
within each of the first and second annular grooves of the
respective stud portion and inner housing to lock the inner housing
to the stud portion and to fixedly couple the outer housing to the
stud portion.
2. The spinal fixation device according to claim 1, wherein the
stud portion includes a cylindrical configuration.
3. The spinal fixation device according to claim 2, wherein the
inner housing includes a bore having a cylindrical configuration
which is configured to at least partially cover the stud portion
when the inner housing is positioned through a bore of the outer
housing.
4. The spinal fixation device according to claim 3, wherein the
stud portion defines at least one opening that is alignable with an
opening defined in the inner housing and an opening defined through
the outer housing when the inner housing is positioned through the
outer housing and on the stud portion.
5. The spinal fixation device according to claim 4, wherein a pin
is receivable within the openings of the stud portion, the inner
housing and the outer housing to prevent rotation of the inner
housing with respect to the outer housing and body portion and
align the inner housing with the outer housing for maintaining a
fixed relationship between the inner housing and the outer
housing.
6. The spinal fixation device according to claim 3, wherein the
bore and the opening defined through the outer housing are oriented
perpendicular with respect to one another.
7. The spinal fixation device according to claim 1, wherein the
inner housing includes two upright arms that are spaced-apart from
one another to define a generally U-shaped slot configured to
receive a spinal rod.
8. The spinal fixation device according to claim 7, wherein the two
upright arms of the inner housing are flexible and configured to
releasably connect the spinal rod within the slot.
9. The spinal fixation device according to claim 8, wherein the
inner and outer housing assume a first, unlocked position in which
the upright arms are permitted to flex to receive a spinal rod, and
a second, locked position in which the inner and outer housings are
taper locked so that the upright arms grip the rod to secure the
rod to the spinal fixation device.
10. The spinal fixation device according to claim 9, wherein top
surfaces of the inner and outer housings are substantially
co-planar.
11. The spinal fixation device according to claim 1, wherein the
body portion includes a bottom portion having a hook configuration
that is configured to engage a lamina of a vertebra of a
patient.
12. The spinal fixation device according to claim 1, wherein the
body portion includes a bottom portion having an elongated
configuration that is configured to connect to at least one other
spinal fixation device.
13. The spinal fixation device according to claim 1, wherein the
ring member is flexible.
14. The spinal fixation device according to claim 13, wherein the
ring member includes a C-shaped configuration, which allows the
ring member to flex, thereby allowing the ring member to expand for
attachment to the stud portion.
15. The spinal fixation device according to claim 1, wherein the
ring member has an inner diameter that is slightly less than an
outer diameter of the first annular groove of the stud portion.
16. The spinal fixation device according to claim 15, wherein the
ring member has an outer diameter that is slightly greater than an
inner diameter of an interior of the inner housing such that the
ring member is receivable within both the first annular groove of
the stud portion and the second annular groove of the inner housing
to lock the inner housing to the body portion.
17. A method for assembling a spinal fixation device, comprising:
positioning an outer housing on a stud portion of a body portion of
the spinal fixation device, the stud portion defining a first
annular groove; positioning a ring member within the first annular
groove defined on the stud portion; and positioning an inner
housing on the stud portion to engage the ring member with a second
annular groove defined on the inner housing to lock the inner
housing to the stud portion and to fixedly couple the outer housing
to the stud portion.
18. The method according to claim 17, wherein positioning the inner
housing on the stud portion to engage the ring member with the
second annular groove further includes moving a distal end of the
inner housing distally past the first annular groove until the ring
member is received within the second annular groove.
19. A method for connecting a spinal rod to a spine of a patient,
comprising: providing a first spinal fixation device, comprising: a
body portion including a stud portion defining a first annular
groove; an outer housing positionable on the stud portion of the
body portion; an inner housing defining a second annular groove,
the inner housing positionable between the outer housing and the
stud portion; and a ring member positionable within each of the
first and second annular grooves of the respective stud portion and
inner housing to lock the inner housing to the body portion and to
fixedly couple the outer housing to the stud portion; positioning a
spinal rod within a slot of the inner housing; moving the outer
housing proximally relative to the inner housing to secure the
spinal rod to the first spinal fixation device; and engaging a
bottom portion of the body portion with a lamina of a vertebra of
the patient to secure the spinal rod to the spine of the
patient.
20. The method according to claim 19, wherein engaging the bottom
portion of the body portion with the lamina of the vertebra of the
patient further includes engaging a hook configuration of the
bottom portion of the body portion with the lamina of the vertebra
of a patient.
21. The method according to claim 19, including connecting at least
a second spinal fixation device to the spinal rod.
22. The method according to claim 21, including connecting an
elongated configuration of a bottom portion of a body portion of
the at least second spinal fixation device to at least a third
spinal fixation device.
Description
BACKGROUND
[0001] 1. Technical Field
[0002] The present disclosure relates to spinal fixation devices.
More particularly, the present disclosure relates to spinal
fixation devices that are connectable to spinal rods used in spinal
constructs.
[0003] 2. Description of Related Art
[0004] There are many known spinal conditions, e.g., scoliosis,
that require the imposition and/or maintenance of corrective forces
on the spine in order to return the spine to its normal condition.
As a result, numerous devices (e.g., alignment systems) have been
developed for use in spinal fixation. One type of spinal construct
may include, for example, one or more spinal rods that can be
placed parallel to the spine with fixation devices (such as hooks,
screws, or plates) interconnected between the spinal rods and
selected portions of the spine. The spinal rods can be connected to
each other via cross-connecting members to provide a more rigid
support and alignment system.
[0005] Usually, the surgeon attaches the spinal fixation devices to
the spine in appropriate anatomical positions and then attaches the
spinal rod to the fixation devices. In conjunction, the surgeon
manipulates the spinal column and/or individual vertebra to provide
the desired treatment for the spinal defect. Subsequently, the
spinal rod and fixation devices are locked in a desired
arrangement.
[0006] While the aforementioned spinal fixation devices are
suitable for the above uses, there may exist a need for spinal
fixation devices that are inexpensive to manufacture and easy to
use.
SUMMARY
[0007] As can be appreciated, spinal fixation devices that are
connectable to spinal rods used in spinal constructs may prove
useful in the surgical arena.
[0008] An aspect of the present disclosure provides a spinal
fixation device. The spinal fixation device includes a body portion
including a stud portion defining a first annular groove. An outer
housing is positionable on the stud portion. An inner housing
defines a second annular groove and is positionable between the
outer housing and the stud portion. A ring member is positionable
within each of the first and second annular grooves of the
respective stud portion and inner housing to lock the inner housing
to the body portion and to fixedly couple the outer housing to the
stud portion.
[0009] The stud portion of the body portion may include a
cylindrical configuration. The inner housing may include a bore
having a cylindrical configuration, which is configured to at least
partially cover the stud portion when the inner housing is
positioned through a bore of the outer housing.
[0010] The stud portion defines at least one opening that is
alignable with an opening defined through the inner housing and an
opening defined through the outer housing when the inner housing is
positioned through the outer housing and on the stud portion. A pin
is receivable within the openings of the stud portion, the inner
housing and the outer housing to prevent rotation of the inner
housing with respect to the outer housing and body portion. The
bore and opening defined through the outer housing may be oriented
perpendicular with respect to one another.
[0011] The inner housing may include two upright arms that are
spaced-apart from one another to form a slot configured to receive
a spinal rod. The two upright arms may be flexible and releasably
connect the spinal rod within the slot. The inner and outer housing
may assume a first, unlocked position in which the upright arms are
permitted to flex to receive a spinal rod, and a second, locked
position in which the inner and outer housings are taper locked so
that the upright arms grip the rod to secure the rod to the spinal
fixation device. Top surfaces of the inner and outer housings may
be substantially co-planar
[0012] The body portion may include a bottom portion having a hook
configuration that is configured to engage a lamina of a vertebra
of a patient. Alternatively, the body portion includes a bottom
portion having an elongated configuration that is configured to
connect to at least one other spinal fixation device.
[0013] The ring member may be flexible and include a C-shaped
configuration, which allows the ring member to flex, thereby
allowing the ring member to expand for attachment to the stud
portion.
[0014] The ring member may have an inner diameter that may be
slightly less than an outer diameter of the stud portion of the
body portion. The ring member may have an outer diameter that is
slightly greater than an inner diameter of the interior of the
inner housing such that the ring member is receivable within both
the first annular groove of the stud portion and the second annular
groove of the inner housing to lock the inner housing to the body
portion.
[0015] An aspect of the present disclosure provides a method for
assembling a spinal fixation device. The spinal fixation device
includes a body portion, an inner housing, an outer housing, and a
ring member. Initially, the ring member is positioned in a first
annular groove of a stud portion of the body portion of the spinal
fixation device. The outer housing is positioned over the stud
portion. Thereafter, the inner housing is positioned on the stud
portion to engage the ring member with a second annular groove
defined on the inner housing to lock the inner housing to the stud
portion and to fixedly couple the outer housing to the stud portion
of the body portion.
[0016] Positioning the inner housing on the stud portion to engage
the ring member with the second annular groove may further include
moving a distal end of the inner housing distally past the first
annular groove until the ring member is received within the second
annular groove.
[0017] Another aspect of the present disclosure provides a method
for connecting a spinal rod to a spine of a patient. A spinal
fixation device is provided and is configured to removably couple
to the spinal rod. The spinal fixation device includes a body
portion including a stud portion defining a first annular groove.
An outer housing is positionable on the stud portion of the body
portion. An inner housing defines a second annular groove and is
positionable between the outer housing and the stud portion. A ring
member is positionable within each of the first and second annular
grooves of the respective stud portion and inner housing to lock
the inner housing to the body portion and to fixedly couple the
outer housing to the stud portion of the body portion. A ring
member is seated within each of the first and second annular
grooves of the respective stud portion and inner housing to lock
the inner housing to the body portion. A spinal rod is, initially,
positioned within a slot of the inner housing. The outer housing is
then moved proximally relative to the inner housing to secure the
spinal rod to the spinal fixation device. Thereafter, the bottom
portion of the body portion is engaged with a lamina of a vertebra
of the patient to secure the spinal rod to the spine of the
patient.
[0018] Engaging the bottom portion of the body portion with the
lamina of the vertebra of the patient may further include engaging
a hook configuration of the bottom portion of the body portion with
the lamina of the vertebra of a patient.
[0019] At least a second spinal fixation device may be connected to
the spinal rod. An elongated configuration of a bottom portion of a
body portion of the at least second spinal fixation device may be
connected to at least a third spinal fixation device.
BRIEF DESCRIPTION OF THE DRAWINGS
[0020] Various embodiments of the present disclosure are described
hereinbelow with references to the drawings, wherein:
[0021] FIG. 1 is a front view of a spinal hook in accordance with
an embodiment of the present disclosure;
[0022] FIG. 2 is a cross-sectional view taken along line A-A of
FIG. 1;
[0023] FIG. 3 is a top plan view of the spinal hook shown in FIG.
1;
[0024] FIG. 4 is a side view of the spinal hook shown in FIG. 1
rotated 90.degree.;
[0025] FIG. 5 is an exploded view of the spinal hook shown in FIG.
1 with parts separated;
[0026] FIG. 6 is a perspective view of the spinal hook shown in
FIG. 1;
[0027] FIG. 7 is a side view of the spinal hook shown in FIG. 1
with a spinal rod positioned in a slot of an inner housing in an
unlocked state;
[0028] FIG. 8 is a side view of the spinal hook shown in FIG. 7
with the spinal rod in a locked state;
[0029] FIG. 9 is an exploded view of a spinal fixation device with
parts separated according to another embodiment of the present
disclosure;
[0030] FIG. 10 is a side view of the spinal fixation device shown
in FIG. 9 with a spinal rod positioned in a slot of an inner
housing in an unlocked state; and
[0031] FIG. 11 is a side view of the spinal hook shown in FIG. 10
with the spinal rod in a locked state.
DETAILED DESCRIPTION
[0032] Detailed embodiments of the present disclosure are disclosed
herein; however, the disclosed embodiments are merely examples of
the disclosure, which may be embodied in various forms. Therefore,
specific structural and functional details disclosed herein are not
to be interpreted as limiting, but merely as a basis for the claims
and as a representative basis for teaching one skilled in the art
to variously employ the present disclosure in virtually any
appropriately detailed structure.
[0033] Embodiments of the present disclosure are described in
detail with reference to the drawing figures wherein like reference
numerals identify similar or identical elements. As used herein,
the term "distal" refers to a bottom portion of the spinal fixation
device, while the term "proximal" refers to a top portion of the
spinal fixation device, as shown in FIG. 1.
[0034] As described above, spinal fixation devices that are
connectable to spinal rods used in spinal constructs may prove
useful in the surgical arena, and such a spinal fixation device is
described herein.
[0035] FIGS. 1 and 2 illustrate a spinal fixation device 10
according to an embodiment of the present disclosure. The spinal
fixation device 10 includes a body portion 12 to which an inner
housing 14 and an outer housing 16 connect. A taper lock is defined
between the inner and outer housings such that in a first position
the spinal fixation is unlocked and able to receive a rod, and in a
second position the taper lock between the inner and outer housings
compresses the spinal fixation device against the rod to secure the
spinal fixation device to the rod. The spinal fixation device 10
may be formed from any suitable biocompatible metal (e.g.,
stainless steel, titanium, titanium alloys, cobalt chrome,
etc.).
[0036] Body portion 12 includes a stud portion 18 having a
generally cylindrical configuration (see FIG. 5 for example). The
stud portion 18 has a diameter that is less than a diameter of a
bore 20 defined through the outer housing 16 (FIGS. 3 and 5) so
that the outer housing 16 may be positioned on the stud portion 18.
The diameter of the stud portion 18 is also less than a diameter of
a bore 22 (FIG. 5) that is defined at least partially through the
inner housing 14 so that the inner housing 14 may be positioned on
the stud portion 18 between the stud portion 18 and the outer
housing 16 (as best seen in FIG. 2). It is noted that in FIG. 2,
the bore 22 defined in the inner housing 14 is not explicitly shown
as the stud portion 18 is shown positioned within the bore 22.
[0037] An annular groove 23 (FIG. 2) is defined in a proximal
portion of the stud portion 18 and is configured to receive a ring
member 25 during manufacture of the spinal fixation device 10, as
described in detail below. An outer diameter of the annular groove
23 is less than an outer diameter of the ring member 25 so that
when the ring member 25 is seated within the annular groove 23, the
ring member 25 extends out from the annular groove 23, the
significance of which is described in detail below.
[0038] An opening 24 is defined through the stud portion 18 and is
alignable with an opening 28 that is defined through the inner
housing 14 and an opening 30 that is defined through the outer
housing 16 (FIGS. 4 and 5). When aligned, the openings 24, 28, and
30 are configured to receive a pin 26 (FIG. 5), which, when
received within the opening 24, 28, and 30, prevents rotation of
the inner housing 14 with respect to the outer housing 16 and stud
portion 18, and aligns the inner housing 14 with the outer housing
16 for maintaining a fixed relationship amongst these parts. In
another embodiment, the pin 26 could also be removed to allow for
movement of the rod locking portion (inner housing 14 and outer
housing 16) with respect to the stud portion 18.
[0039] A bottom portion 32 of the body portion 12 includes a hook
configuration that allows the body portion 12 to be engaged with a
lamina of a vertebra of a patient. The hook configuration may
include a tapered distal end, which may facilitate engaging the
body portion 12 with the lamina of the patient. The bottom portion
32 may include other configurations, as will be described
below.
[0040] The outer housing 16 includes a circumferential
configuration and is positionable on the stud portion 18 of the
body portion 12 (FIGS. 1-3 and 5). The outer housing 16 includes a
tapered proximal end 33 including a plurality of fingers 34 (FIGS.
1 and 5) that are spaced apart along the proximal end 33. The
fingers 34 define a pair of opposing U-shaped channels or slots 43
(FIG. 5) configured to receive a spinal rod 35, which may be
coupled to the inner housing 14 prior to positioning the inner
housing 14 through the bore 20 of the outer housing 16 (see FIGS. 7
and 8 for example). Fingers 34 also define an annular gripping
flange at the proximal end of the outer housing to facilitate
gripping of the outer housing by a locking instrument.
[0041] For a more detailed description of the outer housing 16,
reference is made to U.S. patent application Ser. No. 12/739,461,
the entire contents of which are incorporated herein by
reference.
[0042] The inner housing 14 includes a cylindrical configuration
having a distal end 36 that is insertable through the bore 20 of
the outer housing 16 (FIGS. 2 and 5). The distal end 36 is
configured to rest on an annular flange or lip 38, which extends
along the stud portion 18 of the body portion 12, when the inner
housing 14 is locked to the body portion 12, (FIGS. 2 and 5). The
lip 38 helps support the inner housing 14 when the inner housing 14
is locked to the body portion 12. The distal end 36 of the inner
housing 14 defines the bore 22, which is configured to receive the
stud portion 18 of the body portion 12 so that the inner housing 14
and body portion 12 can be locked together.
[0043] The inner housing 14 includes two upright arms 40 that are
spaced-apart from one another to form a u-shaped slot 42 that is
alignable with the pair of slots 43 on the outer housing 16 to
receive the spinal rod 35 (FIGS. 1, 5, and 7) when the inner
housing 14 is coupled to the outer housing 16. The two upright arms
40 are relatively flexible and releasably connect the spinal rod 35
within the slot 42. Specifically, the dimensions of the slot 42
vary according to the flexure of the upright arms 40. Accordingly,
as the upright arms 40 are moved closer to each other, the slot 42
decreases in size and when the upright arms 40 are moved away from
each other, the slot 42 increases in size. Allowing the slot 42 to
vary in size permits the inner housing 14 to accommodate spinal
rods having differing outside diameters. Alternatively, compressing
the upright arms 40 towards each other increasingly engages the
outer surface of a surgical rod located in the slot 42, thereby
frictionally securing the spinal rod in a desired position.
[0044] In embodiments, the inner and outer housings 14, 16,
respectively, may assume a first, unlocked position in which the
upright arms 40 are permitted to flex to receive a spinal rod (FIG.
7), and a second, locked position in which the inner and outer
housings 14, 16 are taper locked so that the upright arms grip the
rod to secure the rod to the spinal fixation device (FIG. 8).
[0045] The inner housing 14 includes an annular groove 46 that is
defined along an interior wall 47 of the inner housing. In the
illustrated embodiment, the annular groove 46 is disposed at a
proximal end of the interior wall 47. The annular groove 46 is
configured to receive at least a portion of the ring member 25
therein to lock the inner housing 14 to the body portion 12, as
described in detail below.
[0046] Referring to FIG. 5, the ring member 25 may be formed from
any suitable material, e.g., the metals described above. The ring
member 25 includes an inner diameter that is slightly less than an
outer diameter of the stud portion 18 of the body portion 12 and an
outer diameter that is slightly greater than an inner diameter of
the interior of the inner housing 14. This configuration of the
ring member 25 allows the ring member 25 to be received within both
the annular groove 23 of the stud portion 18 and the annular groove
46 of the inner housing 14 to lock the inner housing 14 to the body
portion 12.
[0047] In the illustrated embodiment, the ring member 25 has a
C-shaped configuration, which allows the ring member 25 to flex or
open, thereby allowing the ring member 25 to expand for attachment
to the stud portion 18 during assembly of the spinal fixation
device 10. Specifically, opposing ends 27a, 27b (FIG. 5) of the
ring member 25 are configured to flex or move away from one another
thereby allowing the ring member 25 to be slid or pressed into
position within the annular groove 23 of the stud portion 18. In
embodiments, the ring member 25 can be replaced with a split ring
(not explicitly shown).
[0048] To assemble the spinal fixation device 10, first, the ring
member 25 is positioned within the annular groove 23 on the stud
portion 18 of the body portion 12. In embodiments, this can be
accomplished by pressing or pushing the opposing ends 27a, 27b
against an annular wall portion (not explicitly shown) that defines
the annular groove 23 causing the opposing ends 27a, 27b to move
away from one another and allowing the ring member 25 to be
press-fit into position within the annular groove 23. Next, the
outer housing 16 can then be positioned over the ring member 25 and
along the stud portion 18 of the body portion 12.
[0049] The inner housing 14 is then inserted into the bore 20 of
the outer housing 16 to position the stud portion 18 into the bore
22 of the inner housing 14. The inner housing 14 is pushed distally
along an exterior of the stud portion 18. The force used to push
the distal end 36 distally along the stud portion 18 overcomes the
frictional force of the ring member 25 against the interior wall 47
of the inner housing 14 and allows the inner housing 14 to be
pushed distally along the stud portion 18. In embodiments, as the
distal end 36 is being moved distally along the stud portion 18,
the opposing ends 27a, 27b may move toward each other within the
annular groove 23. Once the distal end 36 of the inner housing 14
reaches the flange 38 of the stud portion 18, the annular groove 46
of the inner housing 14 will be aligned with the annular groove 23
of the stud portion 18 and the ring member 25 will spring into
engagement with the annular groove 46, which, in turn, locks the
inner housing 14 to the body portion 12.
[0050] In the assembled configuration, the spinal fixation device
10 can be utilized to secure a spinal rod to a spine of the
patient. Specifically, referring to FIGS. 7 and 8, in the assembled
configuration, a distal end 31 of the outer housing 16 is
positioned distal of (or below) the flange 38 of the stud portion
18. With the outer housing 16 in this configuration, the spinal rod
35 may be positioned within the slot 42 of the inner housing 14
between the upright arms 40, which will engage the spinal rod 35 to
maintain the spinal rod 35 in a substantially fixed configuration
(FIG. 7).
[0051] Thereafter, the outer housing 16 is moved proximally to
align the plurality of fingers 34 of the outer housing 16 with the
upright arms 40 of the inner housing 14 (FIG. 8). In this aligned
configuration, the tapered proximal end 33 of the outer housing 16
causes an interior surface of the plurality of fingers 34 to
compress the upright arms 40 against the spinal rod 35 to secure
the spinal rod 35 to the spinal fixation device 10. The annular
gripping flange defined by fingers 34 advantageously permits a
locking instrument to engage the proximal portion of the outer
housing 16 to move the outer housing 16 proximally relative to the
inner housing 14 without abutting bone. As shown in FIG. 8, in the
locked position the top surfaces of the inner and outer housings
14, 16, respectively, and the rod are substantially co-planer and
present a low profile above the bone engaged by the hook.
[0052] Thereafter, the hook configuration of the bottom portion 32
of the body portion 12 is engaged with a lamina of a vertebra of
the patient to secure the spinal rod 35 to the spine of the
patient. To release the spinal rod 35 from between the upright arms
40 of the inner housing 14, a user simply pushes the outer housing
16 distally in relation to the inner housing 14 to return the outer
housing 16 to its initial assembled configuration, i.e., the distal
end 31 will again be positioned distal of the flange 38 of the stud
portion 18 (FIG. 7). The spinal rod 35 can then be removed from
within the slot 42 of the inner housing 14. An example of a
suitable locking device and an unlocking device is disclosed in
U.S. Pat. No. 7,988,694, the entire contents of which are hereby
incorporated by reference herein.
[0053] From the foregoing and with reference to the various figure
drawings, those skilled in the art will appreciate that certain
modifications can also be made to the present disclosure without
departing from the scope of the same. For example, while the bottom
portion 22 of the body portion 12 has been described herein as
including a hook configuration, the bottom portion 22 may be
provided with other configurations. For example, FIGS. 9-11
illustrate a spinal fixation device 110 according to another
embodiment. The spinal fixation device 110 is substantially
identical to the spinal fixation device 10 and includes the body
portion 112, the inner housing 114, the outer housing 116 and the
ring 125. Unlike the bottom portion 22, however, the bottom portion
122 of the body portion 112 is in the form of an elongated rod 123,
which may be utilized to connect to another spinal fixation device
10, 110. Other than the bottom portion 122, the spinal fixation
device 110 is identical to the spinal fixation device 10 and,
therefore is not described in further detail.
[0054] The foregoing spinal fixation devices 10, 110 are easy to
use and provide flexibility for a surgeon to generate/create
various spinal constructs and, therefore may prove useful in the
surgical arena.
[0055] In embodiments, the annular groove 23 of the stud portion 18
can be defined along a distal end of the stud portion 18. In this
embodiment, the annular groove 46 of the inner housing 14 can be
defined along a distal end of the interior wall 47, e.g., adjacent
the distal end 36 of the inner housing 14.
[0056] In embodiments, an optional slit 49 (see FIG. 5 for example)
can be defined through the inner housing 14 between the upright
arms 40 to increase the flexibility of the upright arms 40 to
accommodate spinal rods having differing outside diameters.
[0057] While several embodiments of the disclosure have been shown
in the drawings, it is not intended that the disclosure be limited
thereto, as it is intended that the disclosure be as broad in scope
as the art will allow and that the specification be read likewise.
For example, other configurations of the body portion are
contemplated. It also is contemplated that the inner and outer
housing assembly with the ring therebetween may be used to assemble
a taper lock head to a screw, especially to accommodate a screw
head which is too large to enter through the bottom of the outer
housing. Therefore, the above description should not be construed
as limiting, but merely as exemplifications of particular
embodiments. Those skilled in the art will envision other
modifications within the scope and spirit of the claims appended
hereto.
* * * * *