U.S. patent application number 13/728987 was filed with the patent office on 2014-05-22 for illuminated endoscopic pedicle probe with replaceable tip.
The applicant listed for this patent is Avery M. Jackson, III. Invention is credited to Avery M. Jackson, III.
Application Number | 20140142420 13/728987 |
Document ID | / |
Family ID | 49584100 |
Filed Date | 2014-05-22 |
United States Patent
Application |
20140142420 |
Kind Code |
A1 |
Jackson, III; Avery M. |
May 22, 2014 |
Illuminated Endoscopic Pedicle Probe With Replaceable Tip
Abstract
An endoscopic pedicle probe for use during spinal surgery to
form a hole in a pedicle for reception of a pedicle screw has an
enlarged proximal end for cooperation with the hand of the surgeon
and an elongate shaft terminating in a distal tip that may be
pushed through the pedicle to form the hole. The tip may be
detachable for replacement. An endoscope extends through the shaft
and is connected with a monitor to enable the surgeon to visually
observe the area being treated. In a preferred form a light means
extends through the shaft to illuminate the area being treated, and
in a further preferred form a conduit extends through the shaft to
convey a fluid to flush the area being treated. In a further
embodiment, two endoscopes are associated with the probe.
Inventors: |
Jackson, III; Avery M.;
(Grand Blanc, MI) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Jackson, III; Avery M. |
Grand Blanc |
MI |
US |
|
|
Family ID: |
49584100 |
Appl. No.: |
13/728987 |
Filed: |
December 27, 2012 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
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61647747 |
May 16, 2012 |
|
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Current U.S.
Class: |
600/424 ;
600/103; 600/106; 606/84 |
Current CPC
Class: |
A61B 17/3472 20130101;
A61B 17/7074 20130101; A61B 1/00045 20130101; A61B 1/00135
20130101; A61B 1/04 20130101; A61B 1/06 20130101; A61B 1/015
20130101; A61B 1/3135 20130101; A61B 17/00234 20130101; A61B
17/1604 20130101; A61B 17/1655 20130101; A61B 17/1671 20130101;
A61B 17/1615 20130101; A61B 1/126 20130101 |
Class at
Publication: |
600/424 ; 606/84;
600/106; 600/103 |
International
Class: |
A61B 17/16 20060101
A61B017/16; A61B 1/04 20060101 A61B001/04; A61B 1/00 20060101
A61B001/00; A61B 17/00 20060101 A61B017/00; A61B 1/015 20060101
A61B001/015; A61B 19/00 20060101 A61B019/00; A61B 1/06 20060101
A61B001/06 |
Claims
1. A pedicle probe for forming a hole in the hard bony tissue of a
vertebral pedicle to receive a pedicle screw, said pedicle probe
comprising: an enlarged proximal end for cooperation with the hand
of a surgeon using the probe to aid in controlling the probe; an
elongate shaft having a longitudinal axis and extending from the
enlarged proximal end and terminating in a distal end; and a
detachable shaped tip on the distal end of the shaft, said tip
having a reduced diameter relative to the shaft and a hardness and
configuration adapted to be pushed through a pedicle to form a hole
for reception of a pedicle screw, wherein said detachable tip
enables a damaged or worn tip to be replaced, or a tip with
different characteristics to be employed, without replacing the
entire probe.
2. A pedicle probe as claimed in claim 1, wherein: a bore extends
longitudinally through the shaft and an endoscope extends through
said bore, said endoscope including a camera having a lens
positioned to provide a view of an area being treated and said
endoscope being connected with an external monitor for conveying a
visual image of the position of the tip relative to the area being
treated during a surgical procedure, whereby a surgeon is provided
with direct visual indication of the exact position of the probe
during spinal surgery.
3. A pedicle probe as claimed in claim 2, wherein: a second bore
extends longitudinally through the shaft and a light is associated
with said second bore to illuminate the area being treated.
4. A pedicle probe as claimed in claim 2, wherein: the tip is
fluted like a drill bit, and the lens and an opening for receipt of
the lens is positioned in the base of a channel formed between the
flutes.
5. A pedicle probe as claimed in claim 2, wherein: the lens is
positioned rearwardly of the distal point of the tip, whereby the
lens is protected as the probe is inserted into hard bony
material.
6. A pedicle probe as claimed in claim 2, wherein: the lens is
oriented to provide a view at 90.degree. relative to the
longitudinal axis of the shaft.
7. A pedicle probe as claimed in claim 2, wherein: the lens is
oriented to provide a forward view at 45.degree. relative to the
longitudinal axis of the shaft.
8. A pedicle probe as claimed in claim 2, wherein: the lens is
oriented to provide a straight-ahead forward view.
9. A pedicle probe as claimed in claim 3, wherein: a third bore
extends longitudinally through the shaft and a conduit for a fluid
to flush the area being treated extends through said bore to flush
body fluid and debris away from the area being treated.
10. A pedicle probe for forming a hole in the hard bony tissue of a
vertebral pedicle to receive a pedicle screw, said pedicle probe
comprising: an enlarged proximal end for cooperation with the hand
of a surgeon using the probe to aid in controlling the probe; an
elongate shaft having a longitudinal axis and extending from the
enlarged proximal end to a distal end; a reduced diameter tip on
said distal end, said tip having a hardness and configuration
adapted to be pushed through a pedicle to form a hole for reception
of a pedicle screw; a first bore extending longitudinally through
said shaft and a first endoscope associated with said first bore,
said first endoscope including a camera positioned at the distal
end of said shaft and being connected with an endoscopic monitor to
provide a surgeon with a direct view of the area being treated; and
a second bore extending longitudinally through the shaft and a
light associated with said second bore to illuminate the area being
treated.
11. A pedicle probe as claimed in claim 10, wherein: a third bore
extends longitudinally through said shaft and through said tip, and
a second endoscope is associated with said third bore, said second
endoscope including a camera positioned at the distal end of said
tip and being connected with an endoscopic monitor to provide a
surgeon with a direct view of the area being treated.
12. A pedicle probe as claimed in claim 11, wherein: a fourth bore
extends longitudinally through said shaft, and a conduit extends
through said third bore for conveying a fluid to the area being
treated to flush away from the area body fluid and debris that
would otherwise obscure the area being treated.
13. A pedicle probe as claimed in claim 12, wherein: said tip is
detachable from said shaft, whereby said detachable tip enables a
damaged or worn tip to be replaced, or a tip with different
characteristics to be employed, without replacing the entire
probe.
14. A pedicle probe as claimed in claim 13, wherein: said
detachable tip is threadably attached to said shaft.
15. A pedicle probe as claimed in claim 13, wherein: said
detachable tip has a base end received in an axial bore in the
center of the distal end of the shaft, and a set screw extends
through a side of said shaft into engagement with said tip base end
to hold the tip in said axial bore.
16. A pedicle probe as claimed in claim 15, wherein: a coaxial bore
in said base end of said tip is in axial alignment with said first
bore in said shaft, and said coaxial bore in said base end of said
tip connects with an angularly extending diagonal bore opening
through a side of said tip, said camera being positioned in said
diagonal bore where it exits through the side of said tip.
17. A pedicle probe as claimed in claim 16, wherein: said second
and fourth bores open through the distal end of said shaft in
rotationally spaced relationship to one another, said tip being
rotationally oriented relative to said shaft so that said light is
positioned on the same side of said probe as said diagonal bore and
said camera.
18. A pedicle probe as claimed in claim 17, wherein: a keyway is
formed between the base end of said tip and said coaxial bore in
said shaft to rotationally orient said tip when it is attached to
said shaft so that said light is positioned on the same side of
said probe as said diagonal bore and said camera.
19. A pedicle probe for forming a hole in the hard bony tissue of a
vertebral pedicle to receive a pedicle screw, said pedicle probe
comprising: an enlarged proximal end forming a head for cooperation
with the hand of a surgeon using the probe to aid in controlling
the probe; an elongate shaft having a longitudinal axis and
extending from the enlarged proximal end and terminating in a
distal end; a reduced diameter tip on said distal end, said tip
having a hardness and configuration adapted to be pushed through a
pedicle to form a hole for reception of a pedicle screw; at least
one longitudinally extending channel formed in an outer surface of
said shaft; an endoscope extending through said head and through
said at least one channel, said endoscope including a camera at the
distal end of said shaft; and a cylindrical sleeve telescoped over
said shaft and over said at least one channel and endoscope
positioned therein.
20. A pedicle probe as claimed in claim 19, wherein: a second
longitudinally extending channel is formed in the outer surface of
said shaft, and a light means extends through said head and through
said second channel to illuminate an area viewed by said
endoscope.
21. A pedicle probe as claimed in claim 20, wherein: a third
longitudinally extending channel is formed in the outer surface of
said shaft, and a conduit extends through said third channel for
conveying a fluid to the area being treated to flush body fluid and
debris away from the area.
Description
[0001] This application claims the benefit of U.S. provisional
patent application Ser. No. 61/647,747, filed May 16, 2012,
incorporated in full herein by reference.
TECHNICAL FIELD
[0002] This invention relates generally to surgical instruments.
More specifically, the invention relates to a pedicle probe for use
in forming holes in a vertebral pedicle in preparation for pedicle
screw insertion. According to one feature of the invention the
probe incorporates at least one endoscope to enable the surgeon to
see the area being treated. According to another feature the probe
has a light to illuminate the area being treated, and according to
a further feature the probe has a replaceable tip on its distal
end. According to a still further feature the probe has a channel
for directing a flushing fluid to the area being treated to
maintain a clear field of vision for the endoscopic camera. The
probe of the invention may have any one or any combination of these
features.
BACKGROUND ART
[0003] It is sometimes necessary to perform surgery on the spine in
order to repair trauma, correct a deformity, or alleviate the
effects of disease. Spinal fusion or stabilization is one procedure
that may be employed to treat these conditions. According to one
source, at the present time there are approximately 30 million
spine procedures performed globally each year, including
approximately 400,000 cervical and lumbar fixations performed in
the US.
[0004] Spinal fusion may be accomplished by insertion of screws
into the pedicle to stabilize a spinal segment. The pedicle is a
dense, stem-like structure projecting from the posterior of a
vertebra, and there are two pedicles per vertebra that connect to
other structures. Since the pedicle is the strongest point of
attachment of the spine, significant forces can be applied to the
spine without failure of the bone-to-metal connection.
[0005] To insert pedicle screws, a long, thin, metal probe is
inserted through the pedicle and into the vertebral body, forming a
hole for reception of the screw. Conventional pedicle probes may be
straight or curved, and comprise an elongate solid metal shaft with
an enlarged hand grip on the proximal end. The probe may have a
shaped distal end adapted for forming a hole through the pedicle,
or a separate awl or reamer may first be used to form a hole
through the pedicle, and the probe then inserted into the
cancellous bone of the pedicle and into the vertebral body to
develop a path for the screw.
[0006] A variety of probes are known in the prior art, including
the so-called gear shift pedicle probe and the Fox pedicle probe.
The gear shift probe has a round head on its proximal end, whereas
the Fox probe has a flat disc-shaped head on its proximal end.
[0007] Conventional modalities used to approximate or simulate
screw placement are indirect, and include fluoroscopic guidance and
frameless stereotactic guidance. Approximations of the pedicle and
surrounding vital structures are obtained from a CT scan or MRI
done prior to surgery.
[0008] Proper positioning of a conventional probe depends to an
extent upon tactile feel. For instance, advancement of the probe
should be smooth and consistent. A sudden plunge suggests breaking
out of the pedicle laterally, and an increase in resistance
indicates abutment against the pedicle or vertebral body
cortex.
[0009] These conventional modalities require a steep learning
curve, and improper or inaccurate manipulation of the probe and
placement of the pedicle screw can result in caudal or medial
penetration of the pedicle cortex and dural or neural injury.
[0010] With conventional pedicle probes there is no direct way to
confirm that the hole was made within the pedicle and that the
screw will be placed completely inside the pedicle. Surrounding
structures can be injured if a portion of the screw is placed
outside of the pedicle. There can be nerve root injury, epidural
vessel injury, or spinal fluid leakage caused by a misplaced
screw.
[0011] Applicant's earlier U.S. Pat. No. 6,855,105, discloses an
endoscopic pedicle probe having a camera at its distal end
connected with an endoscopic monitor via a fiber optic bundle
extending through the probe to provide the surgeon with a view of
the area being treated, thus overcoming many of the shortcomings of
conventional pedicle probes.
[0012] Notwithstanding the advantages of applicant's earlier
pedicle probe, illumination of the area being treated would greatly
enhance use of the probe. Currently, there are no pedicle probes
having any means to illuminate the pedicle.
[0013] Additionally, the distal tip of the probe can become worn or
damaged during use, rendering the whole instrument unusable or
reducing its usefulness. Further, in some instances a tip having
different characteristics may be desired. A replaceable tip enables
this to be achieved without having to replace the entire
instrument.
[0014] Further, body fluids and debris can accumulate at the area
being treated, blocking or degrading the view provided by the
endoscope. It would be desirable to have a means to flush these
fluids and debris away from the area being treated to maintain a
clear field of view for the endoscope camera.
[0015] Accordingly, there is need for a system and method for
insertion of pedicle screws which eliminates the guesswork and
error-prone modalities of the prior art. In particular, there is
need for a system which provides the surgeon with direct visual
confirmation during the surgical procedure that the pedicle probe
is in the right position for forming a hole for proper placement of
the pedicle screw. Further, there is need for a pedicle probe
having a removable distal tip that can be replaced when necessary
or desired. Still further, there is need for a pedicle probe having
means for illuminating the area being treated. Additionally, there
is need for a pedicle probe having means for directing a fluid to
the area being treated to remove body fluids and debris that might
otherwise obscure the area.
SUMMARY OF THE INVENTION
[0016] The present invention comprises a pedicle probe having means
associated with it to enable the surgeon to directly confirm the
location of the probe during a surgical procedure. More
specifically, the invention comprises a pedicle probe which
provides the surgeon with a visual indication during a surgical
procedure of the position of the probe relative to the pedicle and
surrounding structure, and which, in accordance with one aspect of
the invention, has means to illuminate the pedicle. In accordance
with another aspect of the invention the distal tip of the probe is
replaceable and may be disposable. In a further aspect of the
invention the probe has means associated with it to flush the area
being treated to wash away body fluids and debris that would
otherwise obscure the field of vision.
[0017] In particular, the probe of the invention is an endoscopic
probe having an elongate shaft with a reduced diameter tip on its
distal end. A camera at the distal end is connected with an
endoscopic monitor via a fiber optic bundle extending through the
shaft, and depending upon the positioning of the camera and the
lens employed, the probe of the invention affords the surgeon
direct views of the area being treated, ranging from 0.degree. to
90.degree. relative to the longitudinal axis of the probe shaft,
depending upon the positioning of the endoscope camera.
[0018] In a preferred embodiment a light is associated with the
probe for illuminating the area being treated.
[0019] In another preferred embodiment, the distal tip can be
threaded or otherwise securely removably attached to the forward or
distal end of the shaft so that the tip can be replaced when worn
or damaged or when a tip having different characteristics is
desired.
[0020] In a further preferred embodiment, means is provided on the
probe for flushing the area being treated with a fluid, such as,
e.g. saline, to remove body fluids and debris that might otherwise
obscure the view.
[0021] In one example of the invention, a Fox probe is modified to
have a hollow shaft and a small endoscope is placed in the hollow
shaft, with a camera positioned at the distal end and connected via
a fiber optic bundle with an endoscopic monitor to afford either a
0.degree., a 45.degree. or a 90.degree. view, depending upon the
lens employed and the positioning of the camera.
[0022] The endoscopic pedicle probe of the invention puts the
surgeon "in the pedicle" with the use of endoscopy. The positioning
of the probe can be directly and accurately determined during
surgery, and there is no question as to whether the screw will be
too medial, lateral, cranial, caudal, or deep. The surgeon will
know if the wall of the pedicle has been breached, and to what
extent. He or she can then decide to use the planned trajectory
even if there is a small breach of the pedicle wall. The probe of
the invention provides the surgeon with knowledge of how much of an
intrusion exists, and he or she can ascertain if critical
structures will be in danger from screw placement. The surgeon can
also avoid parallax that may cause errors when using fluoroscopic
guidance.
[0023] Further, a probe must be used in any event to perform spinal
fusions, and the probe of the invention will not represent an
additional instrument needed for pedicle screw placement.
Accordingly, there will be no additional costs or equipment needed
to perform the standard spinal fusion.
[0024] The probe of the invention can be utilized in the cervical
spine for lateral mass screw placement, pedicle screw placement, or
trans-articular screw placement. It can be used in the thoracic,
lumbar, and sacral spine for pedicle screw placement and
trans-laminar screw placement, and can be used in standard open
spine fusion or in minimally invasive percutaneous spine
fusion.
BRIEF DESCRIPTION OF THE DRAWINGS
[0025] The foregoing as well as other objects and advantages of the
invention will become apparent from the following detailed
description when considered in conjunction with the accompanying
drawings, wherein like reference characters designate like parts
throughout the several views, and wherein:
[0026] FIG. 1 is a somewhat schematic perspective view of an
endoscopic pedicle probe according to the invention, in combination
with an endoscopy monitor.
[0027] FIG. 2 is a side view in elevation of a conventional pedicle
probe on which the present invention can be based.
[0028] FIG. 3 is a longitudinal sectional view of a first
embodiment of endoscopic pedicle probe according to the
invention.
[0029] FIG. 4 is an enlarged, fragmentary, longitudinal sectional
view of the distal end of the endoscopic pedicle probe of FIG. 3,
depicting a 90.degree. lens orientation.
[0030] FIG. 5 is a view similar to FIG. 4, but showing a 45.degree.
lens orientation.
[0031] FIG. 6 is a view similar to FIG. 5, but showing a 0.degree.
lens orientation.
[0032] FIG. 7 is an axial view of a pedicle.
[0033] FIG. 8 is a sagittal view of a pedicle.
[0034] FIGS. 9 and 10 are fragmentary perspective views depicting
how a pedicle probe is used to form a hole in a pedicle.
[0035] FIGS. 11-14 are somewhat schematic views depicting the
progressive steps in forming a hole in the pedicle using the
pedicle probe.
[0036] FIG. 15 is an enlarged fragmentary isometric view of the
distal end of one embodiment of pedicle probe according to the
invention, showing light means for illuminating the pedicle.
[0037] FIG. 16 is an enlarged fragmentary isometric view of the
distal end of one embodiment of pedicle probe according to the
invention, showing a removable tip.
[0038] FIG. 17 is a side view in elevation of another embodiment of
pedicle probe according to the invention.
[0039] FIG. 18 is a side view in elevation of the probe of FIG. 17,
taken at 90 degrees to the view in FIG. 17.
[0040] FIG. 19 is an end view of the probe of FIGS. 17 and 18,
taken in the direction of the arrow 19 in FIG. 17.
[0041] FIG. 20 is an end view of the probe of FIGS. 17 and 18,
taken in the direction of the arrow 20 in FIG. 17.
[0042] FIG. 21 is an enlarged fragmentary view in elevation of the
distal end of the shaft and the tip on the distal end in the
embodiment of probe shown in FIGS. 17-20.
[0043] FIG. 22 is a further enlarged fragmentary end view of the
probe of FIG. 21, taken in the direction of the arrow 22 in FIG.
21.
[0044] FIG. 23 is a slightly enlarged fragmentary side view in
elevation of the area indicated generally by the bracket 23 in FIG.
21.
[0045] FIG. 24 is a sectional view taken along line 24-24 in FIG.
19.
[0046] FIG. 25 is a sectional view taken along line 25-25 in FIG.
19.
[0047] FIG. 26 is a fragmentary longitudinal sectional view of
another embodiment of pedicle probe according to the invention.
[0048] FIG. 27 is a fragmentary top isometric view of the probe of
FIG. 26.
[0049] FIG. 28 is an end view in elevation of the probe of FIG. 26,
looking from the left hand side of FIG. 26.
[0050] FIG. 29 is a side view, shown partially in section and
partially in elevation, of a further modified probe according to
the invention, wherein channels are formed in the outer surface of
the probe shaft and feeds for the light, camera and flushing liquid
are placed in these channels, with a surrounding sleeve placed over
the shaft to secure the parts in place.
[0051] FIG. 30 is a transverse sectional view taken long line 30-30
in FIG. 29.
[0052] FIG. 31 is a transverse sectional view taken long line 31-31
in FIG. 29.
[0053] FIG. 32 is an exploded isometric view, with portions broken
away, of the probe and sleeve of FIGS. 29-31.
[0054] FIG. 33 is a fragmentary enlarged sectional view of the
distal end of a further embodiment of the invention wherein a
removable tip is held in place by a set screw and is aligned in
proper position by a keyway.
[0055] FIG. 34 is a transverse view in section taken along line
34-34 in FIG. 33.
[0056] FIG. 35 is a transverse view in section taken along line
35-35 in FIG. 33.
[0057] FIG. 36 is a longitudinal sectional view of a further
embodiment of the invention, taken along line 36-36 in FIG. 37,
wherein two endoscopes are associated with the probe, and a light
means and saline flush means are provided for illuminating the area
being treated and for flushing away debris to maintain a clear
field of view.
[0058] FIG. 37 is an enlarged end view looking in the direction of
the arrow "37" in FIG. 36.
BEST MODES FOR CARRYING OUT THE INVENTION
[0059] Referring more specifically to the drawings, a conventional
Fox pedicle probe is depicted at 10 in FIG. 2. The probe has a
disc-shaped head 11 on its proximal end that is about two inches in
diameter, and a solid metal shaft 12 projecting from the center of
one side thereof. A reduced diameter tip 13 on the distal end of
the shaft is configured to act as a reamer, i.e., it may have a
fluted configuration as found on drill bits. In use, a surgeon
places the disc-shaped head 11 in the palm of his or her hand, with
the shaft extending forwardly. The tip is then pushed against the
pedicle while the probe is being rotated back and forth about the
longitudinal axis of the shaft to form a hole in the pedicle for
reception of a pedicle screw. See, for example, FIGS. 9-14.
[0060] In the specific embodiment illustrated and described herein,
the pedicle probe 20 of the invention, as shown in FIGS. 1 and
3-15, is based on the Fox pedicle probe of FIG. 2. However, it
should be understood that the probe 20 could be based on other
commercially available probes, or could embody a completely new
design. The disc-shaped head 11' of the probe 20 has an opening 21
formed in it for receipt of a fiber optic cable or endoscope 22,
which is connected with a suitable conventional monitor 23.
Similarly, the shaft 12' has a bore 24 formed through its length
for receipt of the fiber optic cable or endoscope 22, which
terminates in the tip 13' at a lens 25. As in conventional pedicle
probes, such as the Fox pedicle probe, the tip 13' is adapted to
penetrate the hard bony tissue of a vertebral pedicle to form a
hole for reception of a pedicle screw.
[0061] As shown in the drawings, the tip has a substantially
uniform diameter through a portion of its length, and terminates in
a sharpened point. The diameter of the tip is approximately the
same as, or slightly smaller than, the diameter of a pedicle screw
to be inserted in the hole formed with the probe, and will form an
elongate hole having a uniform diameter for secure engagement with
a screw inserted in the hole. The tip has a hardness and
configuration to act as a reamer, and preferably has a fluted
configuration as incorporated, for example, in a conventional Fox
pedicle probe, to facilitate penetration of the probe through the
hard bony tissue.
[0062] As shown in FIGS. 4, 5 and 6, respectively, the tip 13' or
13'' or 13''' can be configured to position the lens 25 for
providing a 90.degree. view (FIG. 4), or a 45.degree. forward view
(FIG. 5), or a 0.degree. view straight ahead (FIG. 6). Thus, by
selection of an appropriate probe, or by appropriate manipulation
of a probe, the surgeon can obtain a direct visual indication of
the exact position of the probe in the pedicle and of the pedicle
itself and surrounding structure. As depicted in these figures, the
lens is placed rearwardly of the distal point of the end to protect
it when the probe is pressed against and pushed through hard bony
tissue. An obturator, not shown, may be provided to close the
opening through the side of the tip and protect the lens 25.
[0063] A second embodiment of probe 30 is shown in FIG. 15. In this
modification a suitable light 31 is placed at the distal end of the
shaft 12' adjacent the base end of the tip 13'. The light 31 is
connected via fiber optics 32 or other suitable means extended
through the shaft 12' and connected with a suitable light source
(not shown) external of the probe, and may be positioned to face
axially forwardly of the shaft, as shown in FIG. 15, or at an angle
to the longitudinal axis of the probe. In use, the light
illuminates the pedicle in the area being treated to provide the
surgeon with enhanced visibility of the area as observed through
the lens 25 of the endoscope 22.
[0064] FIG. 16 depicts a third embodiment 40 of pedicle probe in
which the tip 41 is removable. In the example shown the removable
tip has a threaded connection 42 with the shaft 12'', but other
means (not shown) of securely removably attaching the tip 41 to the
shaft could be utilized. The removable tip may be made of any
suitable material, including carbon fiber, and enables tips with
different designs to be used on the probe and also enables the tip
to be replaced if it becomes worn or damaged during use, thereby
avoiding the necessity of having to replace or dispose of the
entire probe. The removable tip may be used without either the
endoscope of FIGS. 3-6 or the light of FIG. 15, or it may be used
in combination with either or both the endoscope and light, shown
as optional features in broken lines at 25 and 31 in FIG. 16.
[0065] FIGS. 7 and 8 are axial and sagittal views, respectively, of
a pedicle P, and FIGS. 9-14 are schematic illustrations of how a
probe 20 might be used to form a hole in the pedicle. Thus, and as
seen especially in FIGS. 10-14, the probe is pushed through the
pedicle to form a hole for reception of a pedicle screw (not
shown). Depending upon the structure of the tip 13' the probe also
may be rotated back and forth to assist in forming the hole. Great
care must be exercised to insure that the probe stays within the
pedicle and does not break through the wall, or does not go too
deep.
[0066] A fourth embodiment 50 of pedicle probe according to the
invention is shown in FIGS. 17-25. The probe 50 has an enlarged
generally disc-shaped head 51 on its proximal end for grasping by
the surgeon as in the previous embodiments, an elongate reduced
diameter shaft 52 projecting from the center of one side of the
head, and a further reduced diameter tip 53 extending coaxially
from the distal end of the shaft. The head comprises a
circumferential rim 54 connected to the proximal end of the shaft
52 by at least two spokes 55A and 55B that join the rim with a hub
56 on the proximal end of the shaft. The outer surface of the rim
is longitudinally fluted at 57, and two circumferentially spaced
recesses 58 and 59 are formed in the upwardly facing proximal end
surface 60 of the rim. As used herein, "upwardly facing" refers to
the orientation when the probe is in its operative position during
use. In the particular construction shown, the recesses are in
alignment with respective flutes 57 and are circumferentially
spaced apart 90 degrees. Two bores 61 and 62 are formed
longitudinally through the hub and shaft in positions oriented
respectively on a radius extending through a respective recess 58
or 59. One of the bores 62 exits the distal end of the shaft in an
axially forwardly facing shoulder 63 between the base end of the
tip and the adjacent end of the shaft. The other bore 61 ends in a
slot 64 formed in the side of the shaft at its distal end and
extending angularly at an angle .beta. of 16 degrees relative to
the longitudinal axis of the shaft into the base end of the tip. A
bore 65 extends from the slot and diagonally through the tip to
exit an opposite side of the tip, providing a view extending over
an angle .alpha. of 74 degrees.
[0067] A fifth embodiment 70 of pedicle probe according to the
invention is shown in FIGS. 26-28. In this embodiment, the proximal
end or head 71 of the probe has a central opening 72 extending
inwardly from its axially upwardly facing surface 73, and a
plurality of bores 74, 75 and 76 extend longitudinally through the
shaft 77 from the base of the opening. A radial notch 78 in the
axially upwardly facing surface connects the central opening with
the outer circumference of the head. An endoscope 22, light 31, and
conduit 79 for conveying a flushing fluid to the distal end of the
probe to remove body fluids and debris from the area being worked
on extend through the notch 78 and through the bores 74, 75 and 76,
respectively. Although not shown in FIGS. 26-28, the bores 74, 75
and 76 could exit through the shoulder between the base end of the
tip and the distal end of the shaft (see, e.g. shoulder 63 in FIGS.
24 and 25), or the endoscope bore could terminate in a slot such as
slot 64 seen in FIGS. 21-23. Also not shown in FIGS. 26-28, the tip
could be integrally formed with the shaft as seen in FIGS. 17-25 or
it could be detachable as seen in FIG. 16.
[0068] A sixth embodiment 80 of pedicle probe according to the
invention is shown in FIGS. 29-32. In this form of the invention,
rather than extend bores longitudinally through the body of the
shaft for containing the endoscope, light and conduit for the
flushing fluid, longitudinally extending channels 81, 82 and 83 are
formed in the outer surface of the shaft 84, and a cylindrical
sleeve 85 is positioned in snug relationship over the shaft in
enclosing relationship to the channels and the endoscope 22, light
31 and conduit 79 held therein. As in the previous embodiments, the
tip may be integral with the shaft or detachable. Similarly to the
embodiment shown in FIGS. 26-28, the head 71' has a central opening
72' and the endoscope 22, light 31 and flushing conduit 79 are fed
through a notch 78' in the end surface of the head.
[0069] A seventh embodiment 90 of pedicle probe according to the
invention is shown in FIGS. 33-35. In this form of the invention,
the tip 91 is detachably secured to the distal end of the shaft 92
by a set screw 93 extended through the side of the shaft and into
engagement with the base end 94 of the tip, which is inserted into
an axial bore 95 in the distal end of the shaft. Proper rotational
positioning of the tip relative to the shaft is achieved by a
keyway formed by an axially extending groove or slot 96 in the
interior surface of bore 95 and a complementally shaped key 97 on
the exterior of the base end 94 of the tip. The tip may be readily
detached from the shaft by loosening the set screw and may be used
with any of the previous forms of the invention. An endoscope 22
and/or a light 31 and/or a conduit 79 for flushing fluid, all shown
in FIGS. 33-35, may be used in combination with the detachable tip,
or the detachable tip may be used without any of these. As seen in
FIG. 35, the outlet for the flushing fluid may have numerous small
orifices 98 to provide a "soft" flow of flushing fluid against the
area being treated.
[0070] An eighth embodiment 100 of probe according to the invention
is shown in FIGS. 35 and 36. In this embodiment, two endoscopes 101
and 102 are provided in the probe. One of the endoscopes 101 has
its camera 103 positioned at the distal end of the tip 104 in a
zero degree forwardly facing orientation. The other endoscope 102
has its camera 105 positioned at the distal end 106 of the probe
shaft 107 and oriented in a camera window slot 108 to provide about
a 70.degree. view looking at the side of the pedicle wall. A bright
fiber optic light source 109 is positioned at the distal end of the
probe shaft adjacent the window for the camera 105. The light
illuminates the pedicle and surrounding bony structures which will
give visualization within the cancellous portion of the pedicle. A
saline rinse port 110 also preferably is provided at the distal end
of the probe shaft to rinse away debris during use of the probe to
keep the field of vision clear.
[0071] One example of a suitable endoscopic camera for use in the
probe of the invention is the 1.2 mm micro camera available from
Medigus, Ltd. of Omer, Israel. This camera has a diameter of only
1.2 mm and a length of only 5 mm. It has high quality 100 degree
FOV optics and a shielded camera cable with a metal connector as
well as a video processor.
[0072] In a typical example of a probe made in accordance with the
invention the shaft can have a length of about 28 cm and a diameter
of from about 6 mm to about 12 mm; the tip can have a length of
about 40 mm and a diameter of from 4 to about 5 mm; and the
endoscope 22, light 32 and conduit 79 for flushing fluid each can
have a diameter of from about 1 mm to about 2 mm. In those
embodiments wherein the camera for the endoscope is located
adjacent the proximal end of the tip, it can be placed along the
tip a distance spaced approximately 6 to 8 mm from where the tip is
joined to the end of the shaft, and preferably is oriented at an
angle of 45 to 90 degrees relative to the longitudinal axis of the
tip. It should be noted that these are exemplary dimensions only
and the probe and its components could have other dimensions as
necessary or desirable.
[0073] The endoscopic probe of the invention provides the surgeon
with an illuminated, direct visual indication of the exact location
of the probe and provides for flushing body fluids and debris away
from the area being treated, whereby the hole can be formed with
accuracy and precision.
[0074] While particular embodiments of the invention have been
illustrated and described in detail herein, it should be understood
that various changes and modifications may be made to the invention
without departing from the spirit and intent of the invention as
defined by the scope of the appended claims.
* * * * *