U.S. patent application number 17/358000 was filed with the patent office on 2022-01-27 for devices and methods for guidewire extension in spinal surgery.
The applicant listed for this patent is CoreLink, LLC. Invention is credited to Jason Althoff, Nick Scodary.
Application Number | 20220023599 17/358000 |
Document ID | / |
Family ID | |
Filed Date | 2022-01-27 |
United States Patent
Application |
20220023599 |
Kind Code |
A1 |
Althoff; Jason ; et
al. |
January 27, 2022 |
DEVICES AND METHODS FOR GUIDEWIRE EXTENSION IN SPINAL SURGERY
Abstract
A guidewire system for spine surgeries includes a first
guidewire portion having an elongate first guidewire body with a
distal end and a proximal end. A threaded male fastener at the
distal end of the first guidewire body is configured to fasten to a
vertebra of a spine of a subject and a threaded female coupler at
the proximal end of the first guidewire body defines a threaded
opening. The guidewire system includes a second guidewire portion
having an elongate second guidewire body with a distal end and a
proximal end. A threaded male coupler at the distal end of the
second guidewire body is configured to thread into the threaded
female coupler of the first guidewire portion to fasten the second
guidewire portion to the first guidewire portion to form an
elongate guidewire.
Inventors: |
Althoff; Jason; (St. Louis,
MO) ; Scodary; Nick; (St. Louis, MO) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
CoreLink, LLC |
St, Louis |
MO |
US |
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|
Appl. No.: |
17/358000 |
Filed: |
June 25, 2021 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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15998473 |
Aug 15, 2018 |
11052229 |
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17358000 |
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62545574 |
Aug 15, 2017 |
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International
Class: |
A61M 25/09 20060101
A61M025/09; A61F 2/46 20060101 A61F002/46 |
Claims
1. A guidewire system for spine surgeries comprising: a first
guidewire portion including an elongate first guidewire body having
a distal end, a proximal end, and a longitudinal axis extending
between the distal and proximal ends, a threaded male fastener at
the distal end of the first guidewire body and extending distally
therefrom, the threaded male fastener being configured to fasten to
a vertebra of a spine of a subject, and a threaded female coupler
extending distally from the proximal end of the first guidewire
body and defining a threaded opening; and a second guidewire
portion including an elongate second guidewire body having a distal
end, a proximal end, and a longitudinal axis extending between the
distal and proximal ends, and a threaded male coupler at the distal
end of the second guidewire body and extending distally therefrom,
the threaded male coupler being adapted to thread into the threaded
female coupler of the first guidewire portion to fasten the second
guidewire portion to the first guidewire portion to form an
elongate guidewire.
2. The guidewire system of claim 1 wherein the first guidewire
portion is identical to the second guidewire portion.
3. The guidewire system of claim 1 wherein the male fastener is
adapted to fasten to the vertebra indirectly through use of a
spinal anchor.
4. The guidewire system of claim 1 wherein a threaded section of
the threaded female coupler is spaced at a distance along the
longitudinal axis from the proximal end of the first guidewire
body, and the threaded male coupler is insertable along said
distance without threading.
5. The guidewire system of claim 1 wherein the proximal end of the
first guidewire portion is configured to mate with the distal end
of the second guidewire portion when the threaded male coupler is
threaded into the threaded female coupler.
6. The guidewire system of claim 5 wherein the male coupler of the
second guidewire portion has a rounded distal end.
7. The guidewire system of claim 5, the threaded female coupler of
the first guidewire portion further comprising: a wall defining a
threaded hole; a threaded section wherein the wall is threaded; and
a shank section wherein the wall is not threaded, the shank section
located between the threaded section and the proximal end of the
first guidewire body.
8. The guidewire system of claim 1 wherein the threaded male
fastener is configured to thread into a vertebra of a spine of a
subject.
9. The guidewire system of claim 8 wherein the first guidewire
portion and the second guidewire portion are identical.
10. The guidewire system of claim 8, the threaded female coupler of
the first guidewire further comprising a wall defining the threaded
opening, the wall having: a threaded section; and a shank section
between the proximal end of the first guidewire portion and the
threaded section; and the threaded male coupler of the second
guidewire portion further comprising: a threaded section; and a
non-threaded shank section between the threaded section and the
distal end of the second guidewire portion, the shank section
adapted to fit in the shank section of the female threaded coupler
when the threaded male coupler is threaded into the threaded
female.
11. The guidewire system of claim 8, further comprising a third
guidewire portion, the third guidewire portion comprising an
elongate third guidewire body having a distal end, a proximal end,
and a longitudinal axis extending between the distal and proximal
ends, and a threaded male coupler at the distal end of the third
guidewire body and extending distally therefrom, the threaded male
coupler of the third guidewire portion being adapted to thread into
the threaded female coupler of the first guidewire portion to
fasten the third guidewire portion to the first guidewire portion
to form an elongate guidewire; and wherein the second guidewire
portion has a length and the third guidewire portion has a length
different from the length of the second guidewire portion.
12. A guidewire for spinal surgeries comprising: an elongate
guidewire body including a distal end, a proximal end, and a
longitudinal axis extending between the distal and proximal ends; a
threaded male fastener at the distal end of the guidewire body and
extending distally therefrom, the threaded male fastener being
adapted to thread into a vertebra of a spine of a subject, and a
threaded female coupler extending distally from the proximal end of
the guidewire body.
13. A combination including the guidewire of claim 12 and a
guidewire extender, the guidewire extender comprising: an elongate
extender body including a distal end, a proximal end, and a
longitudinal axis extending between the distal and proximal ends;
and a threaded male coupler extending along the longitudinal axis
from the distal end, the threaded male coupler configured to thread
into the threaded female coupler of the guidewire.
14. The combination of claim 13, wherein the proximal end of the
guidewire and the distal end of the guidewire extender mate when
the guidewire extender is fully threaded into the guidewire.
15. The combination of claim 13, wherein the guidewire extender is
a first guidewire extender, and wherein the combination further
comprises a second guidewire extender, the second guidewire
extender comprising: a second elongate extender body including a
distal end, a proximal end, and a longitudinal axis extending
between the distal and proximal ends; and a second threaded male
coupler extending along the longitudinal axis from the distal end,
the second threaded male coupler configured to thread into the
threaded female coupler of the guidewire; wherein the first
guidewire extender has a length and the second guidewire extender
has a length different from the length of the first guidewire
extender.
16. A surgical method comprising: threading a threaded male
fastener of a first guidewire portion into a vertebrae of a spine
of a subject to anchor the first guidewire portion to the spine,
wherein the threaded male fastener is at a distal end of an
elongate first guidewire body of the first guidewire portion;
threading a threaded male coupler of a second guidewire portion
into a threaded female coupler at a proximal end of the first
guidewire portion to attach the second guidewire portion to the
first guidewire portion, thereby creating an elongate
guidewire.
17. The surgical method of claim 16 wherein the step of threading
the male coupler into the threaded female coupler comprises
threading the male coupler into the threaded female coupler until
the proximal end of the first guidewire portion mates with the
distal end of the second guidewire portion.
18. The surgical method of claim 16 wherein the vertebra is the
sacrum.
19. The surgical method of claim 16 wherein the first guidewire
portion is threaded directly into the vertebra.
20. The surgical method of claim 16 wherein the step of threading
the threaded male faster of the first guidewire portion into the
vertebra comprises threading the threaded male fastener into a
separate anchor piece and anchoring the anchor piece to the
vertebra.
Description
CROSS-REFERENCE TO RELATED APPLICATION
[0001] The present application claims the benefit of U.S.
Provisional Application No. 62/545,574, filed on Aug. 15, 2017, the
entirety of which is hereby incorporated by reference.
FIELD OF THE DISCLOSURE
[0002] The present disclosure generally relates to spinal surgery
guidewires and methods.
BACKGROUND
[0003] Spinal surgeries, including sacroiliac joint fusion, often
utilize guidewires that anchor into the spine to guide surgical
instruments, etc. to the correct position. Generally, prior art
guidewires are only one piece with a non-adjustable length.
SUMMARY
[0004] In one aspect, a guidewire system for spine surgeries
generally comprises a first guidewire portion including an elongate
first guidewire body having a distal end, a proximal end, and a
longitudinal axis extending between the distal and proximal ends. A
threaded male fastener at the distal end of the first guidewire
body extends distally therefrom. The threaded male fastener is
configured to fasten to a vertebra of a spine of a subject. A
threaded female coupler extends distally from the proximal end of
the first guidewire body and defines a threaded opening. A second
guidewire portion includes an elongate second guidewire body having
a distal end, a proximal end, and a longitudinal axis extending
between the distal and proximal ends. A threaded male coupler at
the distal end of the second guidewire body extends distally
therefrom. The threaded male coupler is adapted to thread into the
threaded female coupler of the first guidewire portion to fasten
the second guidewire portion to the first guidewire portion to form
an elongate guidewire.
[0005] In another aspect, a guidewire for spinal surgeries
generally comprises an elongate guidewire body including a distal
end, a proximal end, and a longitudinal axis extending between the
distal and proximal ends. A threaded male fastener at the distal
end of the guidewire body extends distally therefrom. The threaded
male fastener is adapted to thread into a vertebra of a spine of a
subject. A threaded female coupler extends distally from the
proximal end of the guidewire body.
[0006] In yet another aspect, a surgical method generally comprises
threading a threaded male fastener of a first guidewire portion
into a vertebra of a spine of a subject to anchor the first
guidewire portion to the spine. The threaded male fastener is at a
distal end of an elongate first guidewire body of the first
guidewire portion. A threaded male coupler of a second guidewire
portion is threaded into a threaded female coupler at a proximal
end of the first guidewire portion to attach the second guidewire
portion to the first guidewire portion, thereby creating an
elongate guidewire.
[0007] Other aspects and features will be in part apparent and in
part pointed out hereinafter.
BRIEF DESCRIPTION OF THE DRAWINGS
[0008] FIG. 1 is a side elevation of a human spine;
[0009] FIG. 2A is an elevation of a first guidewire portion of a
guidewire system;
[0010] FIG. 2B is an elevation of a second guidewire portion of the
guidewire system;
[0011] FIG. 3 is an enlarged view of a section of the first
guidewire portion as indicated in FIG. 2A;
[0012] FIG. 4 is an enlarged fragmentary section taken through line
4-4 in FIG. 2A;
[0013] FIG. 5 is an enlarged view of a section of the second
guidewire portion as indicated in FIG. 2B;
[0014] FIG. 6 is a front elevation of a first guidewire portion
threading into the sacrum; and
[0015] FIG. 7 is a front elevation of a second guidewire portion
threading into a first guidewire portion that is threaded into the
sacrum.
[0016] Corresponding reference characters indicate corresponding
parts throughout the drawings.
DETAILED DESCRIPTION
[0017] Referring to FIG. 1, a spine is generally indicated at SP.
Near the bottom of the spine, the sacrum is indicated at S. The
present application discloses methods and associated devices
applicable to multiple spinal surgeries and includes sacroiliac
joint SIJ fusion as a non-limiting example. The devices and methods
disclosed are well-suited to SIJ fusion, but it will be apparent to
one of skill in the art that other applications are possible
without departing from the scope of the present disclosure.
[0018] Referring to FIGS. 2A and 2B, a guidewire system for a
spinal surgery is generally indicated at 10. A first guidewire
portion 12, which can also be considered a guidewire, is configured
to be anchored to a vertebra of the spine, and a second guidewire
portion 42, which can also be considered a guidewire extender, is
configured to thread into the first guidewire portion 12 to provide
a guidewire of a length appropriate for the surgery. More
specifically, the first guidewire portion 12 comprises a threaded
female coupler, generally indicated at 26, and the second guidewire
portion 42 comprises a threaded male coupler, generally indicated
at 50, which threads into (e.g., connects to) the threaded female
coupler 26. This arrangement allows a surgeon to use the first
guidewire portion 12 without regard to whether it is long enough.
If the first guidewire portion 12 is not long enough, then the
second guidewire portion 42 is used to extend the length of the
guidewire system 10. The second guidewire portion 42 does not need
to be used if the length of the first guidewire portion 12 is
suitable. Examples of factors that affect how much guidewire length
is necessary include the size of a subject undergoing surgery and
the type of surgery. In addition, it may be beneficial to initially
use the first guidewire portion 12 for installing in the spine SP
since the first guidewire portion will be shorter, less likely to
bend, and easier to control than a guidewire having an increased
length, such as the combination of the first and second guidewire
portions 10. However, the shorter guidewire (e.g., the first guide
portion 12) may only have a short exposed length extending outside
the patient's body, making it difficult to pass instrumentation
over it. Often times when switching from a drill to a screw driver,
for example, the guidewire can unintendedly travel, particularly
when not exposed behind a working instrument. Because the sacral
foramina have exiting nerves, it is dangerous to have traveling
guidewires in SIJ fusion (as well as percutaneous pedicle screws in
the lumbar spine for anterior vascular risks). The guidewire
extender (e.g., second guidewire portion) 42 allows for a shorter
initial guidewire portion 12 to be secured into desired anatomic
location and then the guidewire system 10 can be extended when
needed. This provides a control point when removing and inserting
other instrumentation and helps prevent unintended guide wire
travel to neural of vascular structures.
[0019] The first guidewire portion 12 comprises an elongate first
guidewire body 14 having a distal end 16, a proximal end 18, and a
longitudinal axis LA, extending between the distal and proximal
ends. The first guidewire potion 12 further comprises a threaded
male fastener, generally indicated at 20, which extends distally
from the distal end 16 of the first guidewire body 14 along the
longitudinal axis LA. The threaded female coupler 26 extends
distally along the longitudinal axis LA from the proximal end 18 of
the first guidewire body 14. In an embodiment, the first guidewire
portion 12 has a length extending between the proximal and distal
ends 18, 16 of, for example, about 300 mm, or from about 200 mm and
about 400 mm, although other lengths are within the scope of the
present disclosure.
[0020] Referring to FIG. 3, the threaded male fastener 20 comprises
a non-threaded section 24 and a threaded section 22. While the
threaded male fastener 20 can be any of various types of fasteners
in other embodiments, in the illustrated embodiment it is a
self-tapping screw. The non-threaded section 24 extends distally
along the longitudinal axis LA from a location at or near the
distal end 16 of the first guidewire body 14 toward the threaded
section 22. A bevel 25 located at the distal end 16 of the first
guidewire body 14 can be included adjacent to or as part of the
threaded male fastener 20. The threaded section 22 of the threaded
male fastener 20 extends distally along the longitudinal axis LA to
a free end that defines a point. In other embodiments the free end
may define a shape other than a point or the threaded section 22
may not extend to the free end of the first guidewire portion 12.
Preferably, the threaded male fastener 20 is configured to thread
directly into (e.g., attach to) the vertebra, but as explained
below, the threaded male fastener can also be configured to attach
to a separate spinal anchor. Other embodiments are possible; for
example, certain embodiments have male fasteners 20 without a
non-threaded section 24. Some embodiments, including some
embodiments configured for use with a spinal anchor, include male
fasteners 20 that form a bolt, non-self-tapping screw, or other
type of fastener. In yet other embodiments, the male fastener 20
may not be threaded and may be configured to be secure to the
sacrum S or other vertebra in other ways.
[0021] Referring to FIG. 4, the threaded female coupler 26
comprises an annular wall 28 and a distal wall 30. In the
illustrated embodiment, the distal wall 30 has a generally conical
shape, but in other embodiments it can be other shapes such as a
flat and circular. The annular wall 28 defines a threaded opening
(e.g., male fastener receiving space) 32 and an entrance 34 at the
proximal end 18 into the threaded opening 32. While the illustrated
embodiment has cylindrical guidewire portions 12, 42 with a
threaded opening 32 (e.g., tapped hole) along the longitudinal axes
LA of the guidewire portions, other shapes for the threaded female
coupler 26 are also contemplated within the scope of the
disclosure.
[0022] The annular wall 28 comprises a shank section 36, a threaded
section 38, and a clearance section 40. The shank section 36 is
generally smooth and extends from a location at or near the
proximal end 18 of the first guidewire body 14 distally along the
longitudinal axis LA towards the threaded section 38. The shank
section 36 may include or be adjacent to a bevel 39 at the proximal
end 18 of the first guidewire body 14. The threaded section 38
extends distally from the shank section 36 towards the clearance
section 40, and is configured to engage the threaded male coupler
50 of the second guidewire portion 42. The clearance section 40 is
generally smooth and extends distally from the threaded section 38
towards the distal wall 30. In other embodiments, by way of
example, the threaded section 38 could extend further along the
longitudinal axis in either the proximal or distal direction or
both directions, eliminating the clearance section 40, the shank
section 36, or both. A taper could also be used in place of the
bevel 39, or the bevel 39 could simply be omitted, among other
changes that could be made without departing from the scope of the
present disclosure.
[0023] The distal wall 30 defines the distal boundary of the
threaded opening 32. In a preferred embodiment, the free end of the
threaded male coupler 50 is spaced a distance along the
longitudinal axis LA from the distal wall 30 even when the threaded
male coupler 50 is fully threaded with the female threaded coupler
26. In this way, guidewire systems 10 with airtight threads provide
room for any air trapped by the threads. Other embodiments are also
possible within the scope of the disclosure.
[0024] Referring again to FIG. 2B, the second guidewire portion 42
comprises an elongate second guidewire body 44 having distal and
proximal ends 46, 48 and a longitudinal axis LA extending between
the distal and proximal ends. The second guidewire portion 42
further comprises a threaded male coupler, generally indicated at
50, extending distally from the distal end 46 of the second
guidewire body 44 along the longitudinal axis LA. A second threaded
female coupler 52 extends distally along the longitudinal axis LA
from the proximal end 48 of the second guidewire body 44, and
defines a second threaded opening 62. The second threaded female
coupler 52 and second threaded opening 62 are the same as threaded
female coupler 26 and opening 32, respectively. Other embodiments
may vary significantly from this exemplary illustration. For
example, the second threaded female coupler 52 may be entirely
absent in some embodiments. In an embodiment the second guidewire
portion 42 has a length extending between the proximal and distal
ends 48, 46 of, for example, about 300 mm, or from about 200 mm to
about 400 mm, although other lengths are within the scope of the
present disclosure.
[0025] Referring to FIG. 5, the threaded male coupler 50 of the
second guidewire portion 42 is configured to thread into the
threaded female coupler 26 of the first guidewire portion 12. The
threaded male coupler 50 comprises a shank section 54, a threaded
section 56, and a rounded end (e.g., free end) 58. The lengths of
the threaded section 56 and the shank section 54 of the threaded
male coupler 50 generally correspond to the lengths of the threaded
section 38 and the shank section 36 of the threaded female coupler
26, respectively. The shank section 54 is generally smooth and
extends distally along the longitudinal axis LA from a location at
or near the distal end 46 of the second guidewire body 44 towards
the threaded section 56. The shank section 54 may include or be
adjacent to a bevel 60 at the distal end 46 of the second guidewire
body 44. The threaded section 56 extends distally, and is
configured to engage the threaded female coupler 26 of the first
guidewire body 14, specifically the threaded section 38. The
rounded end 58 extends distally from a location near the end of the
threaded section 56 and is generally smooth. Preferably, the
rounded end 58 has a length along the longitudinal axis LA of less
than the length along the longitudinal axis LA of the clearance
section 40 of the threaded female fastener 26. In other words, in
the preferred embodiment, the length of the threaded opening 32 of
the threaded female fastener 26 between the proximal end 18 and the
distal wall 30 is greater than the length of the threaded male
coupler 50 between the distal end 46 and the rounded end (e.g.,
free end) 58 so that the male coupler can be completely inserted
into the female coupler with room to spare. In one embodiment, the
rounded end 58 has a sufficient length, such as a length equal to
or greater than the length of the threaded section 56, so that the
rounded end 46 helps facilitate the connection (e.g., insertion) of
the male coupler 50 into the female coupler 26 (e.g., the rounded
end helps guide the male coupler 50 into the female coupler). In
other embodiments, by way of example, the threaded section 56 could
extend further along the longitudinal axis LA in either the
proximal or distal direction or both directions, eliminating the
rounded end 58, the shank section 54, or both. The rounded end 58
could be shaped differently, for example, flat, among other changes
that could be made without departing from the scope of the present
disclosure. In one embodiment, the distal wall 30 of the female
coupler 26 is shaped to correspond to the shape of the end 58 of
the male coupler 50.
[0026] The configuration presented of the threaded female coupler
26 and the threaded male coupler 50 allows the first guidewire
portion 12 and the second guidewire portion 42 to thread (e.g.,
connect) together. In a preferred embodiment, the connection also
allows the distal end 46 of the second guidewire body 44 to mate
(e.g., engage) with the proximal end 18 of the first guidewire body
14 when the threads are fully engaged. Preferably, the threads are
designed so the guidewire system can be threaded until the
guidewire portions mate and so that when the guidewire portions
mate, the threads are tight. Preferably, the first guidewire
portion 12 and the second guidewire portion 42 are also of equal
outer diameters, for example about 0.125 inches across or between
0.075 and 0.25 inches, so that the guidewire system 10 forms an
almost smooth outer surface of the guidewire even at the point
where the guidewire portions meet.
[0027] The first guidewire portion 12 and the second guidewire
portion 42 are identical in some embodiments. In such an
embodiment, the threaded male coupler 50 and threaded male fastener
20 are preferably designed in accordance with the description of
the threaded male fastener 20. The threaded female couplers 26, 52
on both guidewire portions 12, 42 are configured to threadably
receive the interchangeable threaded male fastener 20 or threaded
male coupler 50. Such an embodiment is generally easier and cheaper
to manufacture because only one unique part or no unique part is
manufactured. Moreover, the threads in the threaded sections 22,
38, 46 of the first and second guidewire portions 12, 42 can be
right-handed threads (e.g., standard threads) or left-handed
threads (e.g., reversed-threads).
[0028] In another aspect, a surgical method comprises anchoring a
first guidewire portion to a vertebra or sacrum of the spine and
threading a second guidewire portion into the first guidewire
portion. In some embodiments, the first guidewire portion is
configured to be usable without the second guidewire portion, and
the second guidewire portion is only used when needed or
convenient, for example when operating on a larger patient.
[0029] FIGS. 6 and 7 illustrate a surgical method as applied to
sacroiliac joint fusion (SIJ fusion) using a first guidewire
portion 12 and a second guidewire portion 42. A sacroiliac joint
SIJ and surrounding bones are shown in FIGS. 6 and 7. In SIJ
fusion, an ilium IL of a subject is mechanically fastened to a
sacrum S of the subject to force them to grow together. The
sacroiliac joint SIJ is a large joint that forms where the sacrum S
and the ilium IL meet. In cases where SIJ fusion is found
appropriate, preferably a subject lays down on an operating table,
is sedated, and an operating corridor is made, all according to
methods known in the art. In the embodiment illustrated, the
guidewire system 10 disclosed in FIGS. 2-5 and the accompanying
description is used.
[0030] Referring to FIG. 6, a first guidewire portion 12 of the
guidewire system 10 is then, after the operating corridor is made,
anchored to the sacrum S of the spine of the subject. The guidewire
portion 12 is generally positioned near the middle of the operative
corridor. Preferably the first guidewire portion 12 threads
directly into the sacrum S. Alternatively, a separate spinal anchor
(not shown) may be used, in which case the spinal anchor attaches
at or near the sacrum S and the first guidewire portion 12 attaches
to the spinal anchor.
[0031] Referring to FIG. 7, the second guidewire portion 42 is then
threaded into the first guidewire portion 12 to form an elongate
guidewire system 10 of an appropriate length. In some methods, the
surgeon will first evaluate whether an extra length is needed. When
the guidewire system 10 is installed, any necessary surgical
instruments and tools can be guided precisely to the right point.
As will be apparent to one skilled in the art, the same method and
similar methods can be practiced in a variety of spinal surgeries
without departing from the scope of the disclosure. Among other
differences, applying such a method to other surgeries varies from
the previous description in that a different vertebra may be used.
For example, the second guidewire portion 42 may be used for
percutaneous pedicle screw placement and/or imaged guided placement
of pedicle screws.
[0032] In all embodiments, the guidewire portions 12, 42 are
preferably made from a surgical-grade material that is easy to
sterilize. By way of non-limiting example, stainless steel or
titanium can be used. In other embodiments, the guidewire portions
12, 42 are sealed in sterile containers and intended for single use
only.
[0033] In other embodiments, more than two guidewire portions 12,
42 form the extended guidewire system 10. For example, additional
(e.g., third, fourth, fifth, etc.) guidewire extenders (e.g.,
second guidewire portions) 42 may successively added in series to
the first guidewire extender connected to the first guidewire
portion 12 to create an elongate guidewire system 10 of any desired
length.
[0034] When introducing elements of the present invention or the
preferred embodiment(s) thereof, the articles "a", "an", "the" and
"said" are intended to mean that there are one or more of the
elements. The terms "comprising", "including" and "having" are
intended to be inclusive and mean that there may be additional
elements other than the listed elements.
[0035] As various changes could be made in the above apparatuses,
systems, and methods without departing from the scope of the
invention, it is intended that all matter contained in the above
description and shown in the accompanying drawings shall be
interpreted as illustrative and not in a limiting sense.
* * * * *