U.S. patent number RE33,258 [Application Number 07/126,905] was granted by the patent office on 1990-07-10 for irrigating, cutting and aspirating system for percutaneous surgery.
This patent grant is currently assigned to Surgical Dynamics Inc.. Invention is credited to Leonard Ginsburg, Gary Onik.
United States Patent |
RE33,258 |
Onik , et al. |
July 10, 1990 |
Irrigating, cutting and aspirating system for percutaneous
surgery
Abstract
A percutaneous discectomy system 10 includes a discectomy device
12 having a needle 16 with a port 48 and a flared cutting edge 44
which is actuated past the port 48 to sever tissue provided
adjacent thereto. An irrigation device is 18 are provided for
irrigating the area adjacent the tip 46 of the needle 16 to assist
a vacuum device 22 in aspirating the severed tissue away from the
disc. The discectomy system 10 assists in the removal of herniated
disc tissue in order to relieve pressure on the nerves located
adjacent thereto. In addition, the needle 16 is flexible so that it
can be temporarily or permanently bent around other body tissues
such as the pelvis in order to access discs which are surgically
hard to reach otherwise.
Inventors: |
Onik; Gary (San Francisco,
CA), Ginsburg; Leonard (Oakland, CA) |
Assignee: |
Surgical Dynamics Inc. (San
Leandro, CA)
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Family
ID: |
26825143 |
Appl.
No.: |
07/126,905 |
Filed: |
November 30, 1987 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
Issue Date |
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Reissue of: |
633514 |
Jul 23, 1984 |
04678459 |
Jul 7, 1987 |
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Current U.S.
Class: |
604/22;
606/171 |
Current CPC
Class: |
A61B
17/32002 (20130101); A61B 2017/00261 (20130101); A61B
2017/2905 (20130101) |
Current International
Class: |
A61B
17/32 (20060101); A61B 17/28 (20060101); A61B
17/00 (20060101); A61B 017/32 () |
Field of
Search: |
;128/305,305.1,751,752,755 ;604/22 |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
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1235321 |
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Jun 1971 |
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GB |
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2018601 |
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Oct 1979 |
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GB |
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Primary Examiner: Thaler; Michael H.
Attorney, Agent or Firm: McAulay, Fisher, Nissen &
Goldberg
Claims
I claim:
1. A surgical instrument comprising:
a housing;
a needle supported by said housing, said needle having a forward
portion extending distally of said housing;
said needle including a first elongated tubular wall member
defining a first bore, and having a port formed entirely within the
sidewall of the forward portion of said first tubular wall
member;
said needle including a second elongated tubular wall member
defining a second bore sized to permit passage of tissue
therethrough when said second tubular wall member is connected to a
source of suction, .Iadd.the passage within said second bore being
unobstructed, .Iaddend.said second tubular wall member having a
forward portion extending radially outwardly and terminating in a
cutting edge;
said second tubular wall member being positioned within said first
tubular wall member with said cutting edge in contact with the
sidewall defining said first bore, the forward portion of said
first bore adjacent said port defining a tissue receiving portion
communicating with said second bore;
said first and second tubular wall members being the only tubular
wall members in said forward portion of said needle;
the wall of said second tubular wall member spaced inwardly from
the wall of said first tubular wall member to define the opposing
walls of an annular passageway adapted to be connected to a source
of irrigating fluid, said annular passageway being the sole annular
chamber in said forward portion of said needle;
said second tubular wall member being disposed for movement within
said first tubular wall member to cause said cutting edge to move
from a first position where tissue is drawn through said port into
said tissue receiving portion of said first bore under suction to a
second position where said cutting edge traverses said port to
sever the tissue drawn therethrough, and to permit the severed
tissue to be captured in said tissue receiving portion;
said second tubular wall member having an opening formed in its
sidewall .[.adjacent.]. .Iadd.extending to .Iaddend.said cutting
edge to provide internal communication between said annular
passageway and said second bore to permit direct passage within
said needle of irrigating fluid between said annular passageway
.Iadd.and said tissue receiving portion .Iaddend.and said second
bore;
the forward portion of the sidewall of said first tubular wall
member having no opening rearward of said cutting edge of said
second tubular wall member when said cutting edge is in its first
position;
whereby the severed tissue is evacuated through said second bore
with the aid of the irrigating fluid.
2. The surgical instrument of claim 1 wherein said first tubular
wall member has a cylindrical surface defining said sidewall and a
blunt end wall, said port in said sidewall located adjacent said
blunt end.
3. The surgical instrument of claim 1 further comprising means for
moving said cutting edge of said second tubular wall member between
its first and second positions.
4. The surgical instrument of claim 3 wherein said moving means
includes a diaphragm associated with said second tubular wall
member, and means for exposing said diaphragm to a source of
pulsating positive pressure.
5. The surgical instrument of claim 1 further comprising means for
providing the irrigating fluid to said annular passageway.
6. The surgical instrument of claim 5 further comprising means for
regulating the flow of the irrigating fluid.
7. The surgical instrument of claim 1 further comprising means for
providing the source of suction to said second tubular wall
member.
8. The surgical instrument of claim 1 wherein the flow of
irrigating fluid is "off" when said cutting edge is in its first
position and "on" when said cutting edge is in its second
position.[.;.]. .Iadd.. .Iaddend.
9. The surgical instrument of claim 1 further comprising a cannula
adapted to receive said first tubular wall member.
10. The surgical instrument of claim 9 wherein said cannula is
curved, said first and second tubular wall members being
sufficiently flexible to fit within said curved cannula.
11. The surgical instrument of claim 1 .[.whereinn.]. .Iadd.wherein
.Iaddend.said instrument is a percutaneous discectomy device.
12. A percutaneous discectomy surgical instrument comprising:
a housing;
a needle supported by said housing, said needle having a forward
portion extending distally of said housing;
said needle including a first elongated tubular wall member
defining a first bore, and having a port formed within the sidewall
of the forward portion of said first tubular wall member;
said needle including a second elongated tubular wall member
defining a second bore sized to permit passage of tissue
therethrough when said second tubular wall member is connected to a
source of suction, .Iadd.the passage within said second bore being
unobstructed, .Iaddend.said second tubular wall member having a
forward portion extending radially outwardly and terminating in a
cutting edge;
said second tubular wall member being positioned within said first
tubular wall member with said cutting edge in contact with the
sidewall defining said first bore, the forward portion of said
first bore adjacent said port defining a tissue receiving portion
communicating with said second bore;
said first and second tubular wall members being the only tubular
wall members in said forward portion of said needle;
the wall of said second tubular wall member spaced inwardly from
the wall of said first tubular wall member to define the opposing
walls of an annular passageway adapted to be connected to a source
of irrigating fluid, said annular passageway being the sole annular
chamber in said forward portion of said needle;
said second tubular wall member being disposed for movement within
said first tubular wall member to cause said cutting edge to move
from a first position where tissue is drawn through said port into
said tissue receiving portion of said first bore under suction to a
second position where said cutting edge .[.tranverses.].
.Iadd.traverses .Iaddend.said port to sever the tissue drawn
therethrough, and to permit the severed tissue to be captured in
said tissue receiving portion;
means for moving said cutting edge of said second tubular wall
member between its first and second positions;
said second tubular wall member having an opening formed in its
sidewall .[.adjacent.]. .Iadd.extending to .Iaddend.said cutting
edge to provide internal communication between said annular
passageway and said second bore to permit direct passage within
said needle of irrigating fluid between said annular passageway
.Iadd.and said tissue receiving portion .Iaddend.and said second
bore;
the forward portion of the sidewall of said first tubular wall
member having no opening rearward of said cutting edge of said
second tubular wall member when said cutting edge is in its first
position;
means for providing the irrigating fluid to said annular
passageway; and
means for providing the source of suction to said second tubular
wall member;
whereby the severed tissue is evacuated through said second bore
with the aid of the irrigating fluid.
13. A percutaneous discectomy surgical instrument comprising:
a housing;
a needle supported by said housing, said needle having a forward
portion extending distally of said housing;
said needle including a first elongated tubular wall member
defining a first bore, and having a port formed entirely within the
sidewall of the forward portion of said first tubular wall
member;
said needle including a second elongated tubular wall member
defining a second bore sized to permit passage of tissue
therethrough when said second tubular wall member is connected to a
source of suction, said second tubular wall member having a forward
portion extending radially outwardly and terminating in a cutting
edge;
said second tubular wall member being positioned within said first
tubular wall member with said cutting edge in contact with the
sidewall defining said first bore, the forward portion of said
first bore adjacent said port defining a tissue receiving portion
communicating with said second bore;
the wall of said second tubular wall member being spaced inwardly
from the wall of said first tubular wall member to define the
opposing walls of an annulus, said annulus providing the spacing
for the forward portion of said second tubular wall member to
extend radially outward and provide a cutting edge, said annulus
being the sole annular space in said forward portion of said
needle.[.,.]. .Iadd.; .Iaddend.
a third elongated tubular wall member positioned in said second
bore and defining a passageway adapted to be connected to a source
of irrigating fluid, said passageway being in communication with
said second bore.Iadd., said third tubular wall member being the
sole element in said second bore.Iaddend.;
said third elongated tubular wall member terminating approximately
at said cutting edge of said second tubular wall member to provide
direct passage within said needle of fluid between said third
tubular wall member and said second bore;
said second tubular wall member being disposed for movement within
said first tubular wall member to cause said cutting edge to move
from a first position where tissue is drawn through said port into
said tissue receiving portion of said first bore under suction to a
second position where said cutting edge traverses said port to
sever the tissue drawn therethrough, and to permit the severed
tissue to be captured in said tissue receiving portion;
the forward portion of the sidewall of said first tubular wall
member having no opening rearward of said cutting edge of said
second tubular wall member when said cutting edge is in its first
position;
whereby the severed tissue is evacuated through said second bore
with the aid of the irrigating fluid.
Description
TECHNICAL FIELD
The present invention relates to a surgical cutting device and, in
particular, to a percutaneous discectomy device for removing
nucleus pulposus from a herniated spinal disc.
BACKGROUND ART
An estimated eight million Americans suffer chronic low back pain
due to disc problems requiring a total disability health care
expenditure of over twenty billion dollars. The interverebrate disc
can be looked upon as an osmotic system. .[.Bacuse.]. .Iadd.Because
.Iaddend.of a breakdown of macromolecules as a person ages, the
number of particles in the internal softer tissue of the disc,
known as nucleus pulposus, increases and causes a rise in osmotic
pressure, which in turn causes a fluid influx into the disc and
raises the intradisc pressure. Concomitantly, fissures begin to
form in the fibrous annulus, which defines the outer periphery of
the disc, because of the biomechanical forces placed upon it.
Accordingly, the intervertebral disc may extend through the annulus
thereof and compress nerve roots, causing great pain. The remedy
has been in the past to reduce the mechanical forces that were
causing the increase in disc pressure by placing the patient in
bed. When such conservative therapy failed, the surgical approach
was followed.
A current surgical approach aims at a total disc removal through a
partial hemilaminectomy and thus entails the risks that are
associated with major surgery and general anesthesia. In addition,
costs of this surgery and the in-hospital convalescence required
are large.
Chemonucleolysis has been tried to avoid these problems. The
intradiscal pressure is decreased by the percutaneous introduction
of chymopapain into the intervertebral disc to dissolve it. Such an
approach is effective in the majority of patients but does has some
side effects, as some patients are hypersensitive to the drug.
SUMMARY OF THE INVENTION
The present invention is directed to overcoming all of the problems
associated with prior surgical and drug treatments by providing a
percutaneous discectomy system which can selectively remove
herniated disc tissue in a surgical procedure which does not have
the traumatic effect on the patient associated with prior surgical
procedures. The guillotine type cutting action of the system can
effectively cut the herniated disc tissue into small portions while
the irrigation and vacuum means of the system can efficiently
aspirate the severed herniated disc material and remove same from
the disc, decompressing the disc so as to relieve the pressure.
Such a procedure can allow the patient to be up and about almost
immediately after the procedure has been performed.
The present invention includes a percutaneous discectomy system for
removing intervertebral disc tissue which comprises a probe
including an elongate tubular member with an elongate central bore
and port communicating through the tubular member with the central
bore. The device further includes means for cutting the nucleus
pulposus of the intervertebral disc, said means including another
elongate tubular member having another central bore and a flared
cutting edge. The another elongate tubular member is inserted into
the central bore of the elongate tubular member and substantially
spaced from said central bore of the needle, with the flared
cutting edge contacting the central bore of the needle and
positioned adjacent the port. The another elongate tubular memeber
includes a slot provided through the flared cutting edge so that
the space between the central bore and said another elongate
tubular member communicates with the another central bore.
In another aspect of the invention, means are provided for
communicating internal irrigating fluid in the space defined
between the central bore of the needle and the another elongate
tubular member of the cutting means. This fluid is used to irrigate
the area around the port and the flared cutting edge and to act as
a vehicle for the removal of the severed tissue. The general prior
art includes probe type guillotine cutters which have a source of
irrigating fluid provided externally to the needle adjacent a port.
Such probes with external irrigation have not proven successful for
aspirating disc tissue.
Additionally, to facilitate the removal of the severed tissue, a
source of vacuum is adapted to communicate with the another central
bore of the cutting means so as to aspirate the severed tissue.
Still further means are provided for driving the flared cutting
edge past the port of the needle in a pulsed manner.
Accordingly, the present invention provides for a percutaneous
discectomy device which allows the selected removal of herniated
disc tissue without the major surgical implications of standard
back surgery and without the side effects of chemical surgery. This
system allows the surgery to occur rapidly without the trauma to
the patient which is characteristic of other surgical techniques.
The invention provides a guillotine cutting arrangement, irrigation
system and vacuum or aspiration system which addresses the problem
of cutting and removing disc tissue, which is often dry and
tough.
In another aspect of the invention, both the needle and the cutting
means are flexible so that if the disc tissue is difficult to
reach, the needle and cutting means can be bent to curve around
bone and tissue structures and address the proper disc without the
requirement to drill through, for example, the pelvic bone. This is
particularly important for the disc located between the fifth
lumbar vertebra and the first sacroiliac vertebra. It is to be
understood that the teachings of the present invention can be
applied to other than percutaneous discectomy and fall within the
scope of the claimed invention.
BRIEF DESCRIPTION OF THE FIGURES
FIG. 1 is a partial schematic, partial section view of an
embodiment of the invention.
FIG. 2 depicts a cross-sectional view of the tip of the needle of
the embodiment of the invention of FIG. 1.
FIG. 3 depicts a cross-sectional view similar to FIG. 2 with the
cutting edge of the embodiment positioned midway through a cut.
FIG. 4 is a figure similar to FIG. 2 with the cutting edge all of
the way through a cut.
FIG. 5 is a cross-sectional view taken .[.throuh.]. .Iadd.through
.Iaddend.the line 5--5 in FIG. 2.
FIG. 6 is an alternative embodiment of the invention.
FIG. 7 is yet another alternative embodiment of the invention.
FIG. 8 is a schemiatic view of the needle positioned within a
curved cannula sleeve, with the operative end of the needle exposed
to remove disc tissue.
FIG. 9 is a view similar to FIG. 8 showing the cannula sleeve
straight instead of being curved.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
With respect to the figures and in particular to FIG. 1, an
embodiment of the percutaneous discectomy system of the invention
is depicted and identified by the numeral 10. This descectomy
system includes a hand-held percutaneous discectomy probe 12 which
has a probe body 14 and a probe needle 16. The system further
includes in a preferred embodiment a device 18 for providing and
controlling internal irrigation fluid under pressure, a device 20
for providing a pulsed source of positive pressure to drive the
system and a device 22 for providing a source of vacuum and
collection means for aspirating cut disc tissue. Devices 18, 20, 22
can be included in a single control device console if desired.
The body 14 is comprised of a cylindrical housing 24 which has a
central bore 26 and a back pressure relief vent 27. Disposed at one
end of the central bore 26 is a plug 28 which has a bore 30
provided therethrough. At the front end of the body 14 is a cap 32
which is secured to the body 14 with glue or other appropriate
means. The cap 32 includes a bore 34. Needle 16 is partially
inserted into bore 34 and, in a preferred embodiment, glued in
place. An irrigation passage 36 communicates with bore 34 at a
point adjacent the end of needle 16. This irrigation passage 36
also communicates with the irrigation fluid device 18. The needle
16 defines a central bore 40. Located inside of the central bore 40
of needle 16 and the bore 30 of plug 28 and also the central bore
26 of cylindrical housing 24 is an elongate tubular cutting member
42 which has a flared cutting edge 44 located adjacent the blunt
end 46 of the needle 16. An O-ring 38, located in a groove defined
by cap 32 and located adjacent the plug 28, provides a seal about
tubular member 42.
As will be described more fully hereinbelow, the flared cutting
edge 44 is positioned to pass across port 48 located adjacent blunt
end 46 and provided through the needle 16. The flared cutting edge
44 has a slot 50 therethrough which provides communication between
a central bore 52 of the elongate tubular cutting member 42 and the
space located between the central bore 40 of the needle 16 and the
elongate tubular cutting member 42. The flared cutting edge 44 is
compressed when it is inserted in the central bore 40 of needle 16
in order to increase the effectiveness of the guillotine cutting
action of device 12. The fact that the rest of the tubular cutting
member 42 is spaced from the central bore 40 of needle 16 not only
allows the flow of irrigating fluid, as described below, but also
reduces friction between the needle 16 and member 42.
Provided in the central bore 26 and located about the cutting
member 42 is a spring 54. Secured to elongate tubular cutting
member 42, at the opposite end from cap 32, is a piston 56. Secured
to piston 56 is a flexible diaphragm 58. Diaphragm 58 includes a
peripheral lip 60 which is seated in annular groove 62 defined by
cylindrical housing 24.
A ring member 64 is disposed against the peripheral lip 60 and held
in place by a threaded ring 66. This allows the threaded ring 66 to
be tightened against the ring 64 which holds the peripheral lip 60
of the diaphragm 58 in place without causing the diaphragm to be
pinched or twisted from its position. It is to be understood that
upon .[.assemble.]. .Iadd.assembly.Iaddend., the diaphragm is
positioned so that the slot 50 in the flared cutting edge 44 is
located opposite the port 48 at the blunt end 46 of the needle
16.
Another cap 68 is provided adjacent the piston 56 and includes a
threaded portion which can be threaded to the body 14 adjacent the
threaded ring 66. A chamber 74 is defined between the cap 68 and
the diaphragm 58. The cap 68 includes a central bore 70 which
guides a portion of the piston 56 and cutting member 42 and which
provides a position to seat an O-ring 72, which provides a seal
between the elongate tubular cutting member 42 and the another cap
68. The spring 54 biases the piston 56 and the cutting member 42
against the cap 68 so as to keep the flared cutting edge 44 in a
first position located adjacent the port 48 as shown in FIG. 2.
The vacuum source device 22 is provided in communication with the
central bore 52 of the elongate tubular cutting member 42 .Iadd.by
.Iaddend.aspiration line 55, and the pulsed pressure device 20 is
provided in communication with the chamber 74 through a passage 76
provided in the another cap 68.
The various positions which the cutting edge 44 can occupy relative
to the port 48 are shown in FIGS. 2, 3, 4. In FIG. 2, a first
position is shown with the port 48 fully open. In FIG. 3, the
cutting edge 44 is urged toward the blunt end 46 by pulsed pressure
provided to the chamber 74 from the pressure device 20 to capture
and sever a piece of disc tissue 78. In FIG. 4, the cutting edge 44
has passed completely by the port 48 and has severed the tissue 78
whereby, with the aid of the irrigating fluid shown by the arrows
and the vacuum provided by device 22, the severed tissue is
aspirated into a collection bottle of the device 22. A
cross-sectional view of the needle including the slot of the
cutting edge 44 is depicted in FIG. 5.
In a preferred embodiment, the housing 14 can be comprised of
plastic or other suitable materials, and the needle 16 and the
tubular cutting member 42 can be comprised of flexible stainless
steel tubing with the elongate tubular cutting member .[.44.].
.Iadd.42 .Iaddend.chrome-plated to prevent galling. The needle and
cutting member 42 can be permanently bent to a fixed orientation if
desired or can be temporarily bent if it is provided through a bent
sleeve as will be described hereinbelow.
In a preferred embodiment, the diameter of the needle 16 is 0.084
inches, or approximately 2 millimeters, while the internal diameter
of the central passage 40 of the needle 16 is approximately 0.073
inches with the outer diameter of the tubular cutting member 42
being approximately 0.059 inches. This spacing provides for
sufficient irrigating fluid to be provided to slot 50 in order to
provide irrigation adjacent the port 48.
It is to be understood that other types of cutting arrangement such
as rotating cutters can be used and be within the scope and spirit
of the invention.
Alternate embodiments of the invention are depicted in FIGS. 6 and
7. In FIG. 6, an additional elongate tube 80 is provided inside the
central bore 52 of the tubular cutting member 42. Irrigation fluid
can be provided therethrough into the area adjacent the port 48. In
the other embodiment depicted in FIG. 7, apertures 86 are provided
through the flared portion of member 42 adjacent cutting edge 44.
Apertures 86 provide internal irrigation fluid communication and
allow for a strong cutting edge 44.
It is to be understood that with internal irrigation as provided by
the present invention, irrigation fluid tends not to pass through
port 48 and thus does not interfere with the sucking of tissue into
port 48.
It is also to be understood that in addition to pulsing the source
of positive pressure to drive diaphragm 58 and thus to drive the
cutting edge 44, the irrigation fluid from device 18 as well as the
vacuum from device 22 is also pulsed as follows. The irrigation
fluid is periodically pulsed off or to a reduced flow with the port
48 open so as not to reduce the .[.vacuuum.]. .Iadd.vacuum
.Iaddend.and the efficiency thereof in pulling tissue into the
port. As cutting is completed and the cutting edge 44 closes port
48, the irrigation fluid is pulsed on to assist in removing the
severed tissue through aspiration line 55. The vacuum is pulsed to
prevent clogging of tissue in aspiration line 55 by providing an
impulse to such tissue.
It is further to be understood that device 18 can also control the
irrigation fluid flow rate independently of the above periodic
pulsed flow rate. This second control can be adjusted by the
operator by observing the flow of irrigation fluid and tissue in
the aspiration line 55 which in a preferred embodiment is
substantially clear. If the operator observes a fast irrigation
fluid flow with little tissue, the operator can decrease generally
the flow rate independently of the first periodic pulsed flow rate
so that the vacuum can be more efficient in aspirating tissue. If
the operator observes a slow irrigation flud flow rate with much
tissue, the operator can generally increase the fluid flow rate as
a preventative measure so that tissue clogging does not occur.
INDUSTRIAL APPLICABILITY
The operation of the percutaneous discectomy system 10 is as
follows. Using CT scan techniques and the like, the needle 16 can
be inserted straight-in between the appropriate vertebra and into
the herniated disc. Prior to the insertion of the needle 16, a
small hole can be prepared through the fibrous annular ring which
defines the outer periphery of the disc. The needle is then
inserted through this opening.
As the needle 16 is inserted through the hole drilled in the
periphery of the disc, the irrigation device, the suction device,
and positive pressure device are turned on to operate the
guillotine cutting action of the flared cutting edge 44 relative to
the port 48 and to aspirate tissue. As the needle is inserted
further into and through the disc, additional tissue is severed and
aspirated. Also as the needle is rotated in place, the port 48 is
exposed to different portions of the disc and additional tissue is
severed and aspirated. Once the required amount of tissue is
removed, the needle can be moved from the disc.
It is to be understood that if the disc is located in a
hard-to-reach area such as between the fifth lumbar and the first
sacroiliac vertebrae, then instead of cutting through part of the
pelvis or other tissues or bone structures, an introduction and
delivery system which includes a curved sleeve or cannula .Iadd.90
.Iaddend.as shown in FIG. 8 can be inserted using known techniques,
such as with the aid of the CT scan so as to avoid the bone
obstacles. Such an introduction and delivery system using a
straight sleeve 92 as shown in FIG. 9 can also be used, if desired,
in the above described straight-in procedure. Once the cannula
90,92 is positioned, the flexible needle can be inserted through
the cannula into the disc so as to remove disc tissue along a
linear path. It is to be understood that the port 48 can also be
rotated throughout 360.degree. in order to extract additional
tissue. Further it is to be understood that if desired, the needle
16 can be permanently bent, and without the use of a sleeve or
cannula .Iadd.90, 92 .Iaddend.can be inserted into this position.
However, there is then no opportunity to rotate the port 48 located
in the needle 16 in order to sever and aspirate tissue on a
360.degree. basis. It is also to be understood that such an
introduction and delivery system can be used generally with this
invention and can also include devices for precisely maintaining
the position of the probe relative to the body.
From the above it can be seen that the present invention provides
for a system for removing tissue from a herniated disc without
causing undue trauma to the patient. Additionally the system is
flexible so that it can be positioned in otherwise surgically hard
to reach areas, plus it provides for irrigation of the severed
material to facilitate the aspiration thereof to the collection
vessel. The pulsed vacuum creates impulses in the line which act as
shock waves to further facilitate the aspiration of the tissue and
prevent it from clogging in the needle 16.
Other advantages of the invention can be obtained from a review of
the figures and the appended claims. It is to be understood that
although the present invention was described relative to a
percutaneous discectomy procedure, that a similar system can be
used to remove tissue from other portions of the body or for other
unrelated purposes and fall within the scope of the invention and
the appended claims.
* * * * *