U.S. patent application number 10/905351 was filed with the patent office on 2006-06-29 for abrasive cutting system and method.
This patent application is currently assigned to DEPUY MITEK, INC.. Invention is credited to Douglas W. Dunn, Elizabeth Heneberry, Ian D. McRury, Kevin J. Ranucci, Mehmet Z. Sengun.
Application Number | 20060142773 10/905351 |
Document ID | / |
Family ID | 36121296 |
Filed Date | 2006-06-29 |
United States Patent
Application |
20060142773 |
Kind Code |
A1 |
Sengun; Mehmet Z. ; et
al. |
June 29, 2006 |
ABRASIVE CUTTING SYSTEM AND METHOD
Abstract
A high pressure fluid jet system is provided, which is useful
for cutting hard material during a surgical procedure. The cutting
of hard material is more efficient as the system delivers abrasive
solid particles with the high pressure fluid. In an exemplary
embodiment, abrasive solid particles can be mixed with a
pressurized stream of fluid prior to delivery of the fluid to a
nozzle of an application tool. Alternatively, the abrasive solid
particles can be entrained in the pressurized fluid stream or the
pressurized fluid stream can erode a solid or suspension form of
the abrasive particles.
Inventors: |
Sengun; Mehmet Z.;
(Framingham, MA) ; Heneberry; Elizabeth;
(Westwood, MA) ; McRury; Ian D.; (Medway, MA)
; Ranucci; Kevin J.; (North Attleboro, MA) ; Dunn;
Douglas W.; (Mansfield, MA) |
Correspondence
Address: |
NUTTER MCCLENNEN & FISH LLP
WORLD TRADE CENTER WEST
155 SEAPORT BOULEVARD
BOSTON
MA
02210-2604
US
|
Assignee: |
DEPUY MITEK, INC.
Route 22 West
Somerville
NJ
|
Family ID: |
36121296 |
Appl. No.: |
10/905351 |
Filed: |
December 29, 2004 |
Current U.S.
Class: |
606/79 ;
606/167 |
Current CPC
Class: |
A61B 17/32037 20130101;
A61B 2017/1648 20130101; A61B 17/1644 20130101; A61B 17/3203
20130101 |
Class at
Publication: |
606/079 ;
606/167 |
International
Class: |
A61B 17/16 20060101
A61B017/16 |
Claims
1. A method of effecting cutting during a surgical procedure,
comprising: providing a surgical tool effective to deliver a
pressurized stream of a fluid through a nozzle; and delivering the
pressurized stream of fluid through the surgical tool and out of
the nozzle to hard material within a patient to effect cutting of
the hard material within the patient in a desired pattern such that
the fluid that cuts the hard material includes a delivery liquid
having a plurality of abrasive solid particles formed from an
organic material.
2. The method of claim 1, wherein the delivery liquid is a saline
solution.
3. The method of claim 1, wherein the abrasive solid particles are
bioabsorbable.
4. The method of claim 1, wherein the abrasive solid particles are
selected from the group consisting of polyglycolic acid, polylactic
acid, polyethylene oxide, and blends and copolymers thereof.
5. The method of claim 4, wherein the abrasive solid particles are
formed from particles having a particle size in the range of about
5 to 200 microns.
6. The method of claim 1, wherein the pressurized stream of fluid
is delivered through the nozzle at a pressure in the range of about
1,000 to 20,000 psi.
7. The method of claim 1, wherein the abrasive solid particles are
mixed with the pressurized stream of fluid prior to delivery
through the nozzle.
8. The method of claim 1, wherein the plurality of abrasive solid
particles are entrained in the pressurized fluid stream after the
pressurized fluid stream exits the nozzle.
9. The method of claim 1, wherein the pressurized fluid stream that
exits the nozzle contacts a solid material, at least a portion of
which is eroded by the fluid stream to entrain the plurality of
solid particles in the fluid stream.
10. The method of claim 9, wherein the solid material is a rod
formed of an abrasive material.
11. The method of claim 9, wherein the solid material is a plate
having a solid region and an open region, the open region being
formed in a desired shape and being occluded by an abrasive
agglomerate, such that when the plate is contacted by the
pressurized fluid stream, the hard material is cut in a pattern
that is in the shape of the open region.
12. The method of claim 1, further comprising: providing a cutting
template having a region formed of a solid material resistant to
erosion by the pressurized fluid stream and an opening in said
region forming a cutting region having a size and shape
corresponding to a desired pattern, the cutting region being
occupied by a plug of abrasive material; and directing the
pressurized fluid stream over the cutting template to entrain with
the pressurized fluid stream abrasive solid particles eroded from
the plug of abrasive material to effect cutting of the hard
material.
13. The method of claim 12, wherein the hard material is selected
from the group consisting of bone, bone cement, and
bioadhesives.
14. A system for cutting tissue during a surgical procedure,
comprising: a surgical apparatus effective to deliver a stream of
pressurized fluid; and a plate having a cutting template having a
region formed of a solid material resistant to erosion by the
pressurized fluid and an opening in said region, the opening being
occluded by a plug of abrasive material.
15. The system of claim 14, wherein the opening is formed in the
shape of a desired cutting pattern.
16. The system of claim 14, wherein the abrasive solid particles
are selected from the group consisting of polyglycolic acid,
polylactic acid, polyethylene oxide, and blends and copolymers
thereof.
17. The system of claim 14, wherein the abrasive material formed
from particles having a particle size in the range of about 5 to
200 microns.
Description
FIELD OF THE INVENTION
[0001] The present invention relates to high pressure fluid jet
surgical tools, and in particular to a high pressure fluid jet tool
for cutting hard material during a surgical procedure.
BACKGROUND OF THE INVENTION
[0002] Fluid pressure-based surgical tools for cutting bone and the
like can offer some advantages over traditional surgical cutting
devices and methodologies. In particular, high pressure fluid jets
tend to emulsify the target material, thus avoiding thermal damage
which can arise from using laser cutters and electrosurgical
cutters. The emulsified material can also be easily transported
away from the surgical site by aspiration. Indeed, the fact that
many high pressure fluid jet cutting devices include aspiration and
evacuation as an integral portion of the device can be an added
benefit for many surgical procedures.
[0003] One drawback associated with current fluid pressure-based
surgical systems which are used to cut bone and the like is that
they typically require ultra-high operating pressures, and the
delivery of such hydraulic pressure using a conservatively sized
operating room pump and surgical instruments delicate enough to
meet the surgeon's demands can often be problematic.
[0004] Accordingly, there remains a need for an improved fluid
pressure-based surgical tool, and in particular a fluid
pressure-based surgical tool for cutting hard material.
BRIEF SUMMARY OF THE INVENTION
[0005] Various methods and devices are provided for cutting hard
material, such as bone and the like, during a surgical procedure.
In one exemplary embodiment, a method is provided which includes
delivering a pressurized stream of fluid through a surgical tool to
effect cutting of hard material within a patient. While a variety
of fluids can be used to effect cutting, by way of non-limiting
example, the fluid that cuts the hard material includes a delivery
liquid having a plurality of abrasive solid particles formed from
an organic material. The abrasive solid particles can be formed
from a variety of materials, and in an exemplary embodiment they
are formed from bioabsorbable materials such as polyglycolic acid,
polylactic acid, polyethylene oxide, and blends and copolymers
thereof.
[0006] The present invention also provides various methods for
mixing the abrasive solid particles with the delivery liquid, such
as, for example, mixing the abrasive solid particles with the
pressurized stream of fluid prior to delivery through the nozzle.
In another embodiment, the abrasive solid particles can be
entrained in the pressurized fluid stream after the pressurized
fluid stream exits the nozzle, or, alternatively, the abrasive
solid particles be in the form of a solid or suspended material
that is eroded by the pressurized fluid stream once the fluid
stream exits the nozzle. While the solid material can be a variety
of shapes, by way of non-limiting example, the solid material can
be a rod. Moreover, the solid material can be a plate having a
solid region and an open region. The open region of the plate can
be a variety of configurations, and in one embodiment it can be
formed in a variety of shapes and of a material such that when the
plate is contacted by the pressurized fluid stream, the hard
material is cut in a pattern that is complementary to the shape of
the open region.
[0007] The present invention also provides a system for cutting
tissue during a surgical procedure which includes a surgical
apparatus effective to deliver a stream of pressurized fluid and a
plate with a cutting template. The cutting template can have a
variety of configurations, and in one embodiment, the cutting
template can have a region formed of a solid material which is
resistant to erosion by the pressurized fluid and an opening formed
in said region which is able to be occluded by an erodable plug of
abrasive material.
BRIEF DESCRIPTION OF THE DRAWINGS
[0008] The invention will be more fully understood from the
following detailed description taken in conjunction with the
accompanying drawings, in which:
[0009] FIG. 1A is a schematic illustration of a high pressure fluid
jet system according to one embodiment of the invention;
[0010] FIG. 1B is a schematic illustration of a suspension pump for
use with the high pressure fluid jet system of FIG. 1A;
[0011] FIG. 2 is a schematic illustration of one embodiment of the
present system utilizing a collimating nozzle which allows abrasive
solid particles to be entrained within a pressurized stream of
fluid;
[0012] FIG. 3 is a schematic illustration of another embodiment of
the present system utilizing a high pressure fluid jet system
having a supply of abrasive solid particles;
[0013] FIG. 4A is a schematic illustration of a further embodiment
of the present system utilizing a high pressure fluid jet system
for use with a cutting template that is eroded by a pressurized
stream of fluid; and
[0014] FIG. 4B is top perspective view of a cutting template for
use with the high pressure fluid jet system of FIG. 4A.
DETAILED DESCRIPTION OF THE INVENTION
[0015] Certain exemplary embodiments will now be described to
provide an overall understanding of the principles of the
structure, function, manufacture, and use of the methods and
devices disclosed herein. One or more examples of these embodiments
are illustrated in the accompanying drawings. Those skilled in the
art will understand that the methods and devices specifically
described herein and illustrated in the accompanying drawings are
non-limiting exemplary embodiments and that the scope of the
present invention is defined solely by the claims. The features
illustrated or described in connection with one exemplary
embodiment may be combined with the features of other embodiments.
Such modifications and variations are intended to be included
within the scope of the present invention.
[0016] The present invention provides a high pressure fluid jet
system that is useful, during a surgical procedure, for cutting
hard material. The cutting of hard material is more efficient as
the system delivers abrasive solid particles with the high pressure
fluid. In an exemplary embodiment, abrasive solid particles can be
mixed with a pressurized stream of fluid prior to delivery of the
fluid to a nozzle of an application tool. Alternatively, the
abrasive solid particles can be entrained in the pressurized fluid
stream or the pressurized fluid stream can erode a solid or
suspension form of the abrasive particles. One skilled in the art
will appreciate that the present invention can be used to cut a
variety of hard materials, such as bone, cartilage, bone cement,
bioadhesives, or any other hard material found or used within a
human body, and therefore can be used in a wide range of surgical
procedures.
[0017] A variety of materials can be used to form the abrasive
particles of the present invention, including organic and inorganic
materials. In an exemplary embodiment, the abrasive particles are
biocompatible and bioabsorbable. One skilled in the art will
appreciate that the materials can be crystalline or amorphous.
Further, the crystalline materials can include ice and other frozen
materials.
[0018] Examples of suitable bioasborbable materials that can be
used to form the abrasive particles include polymers selected from
the group consisting of aliphatic polyesters, poly(amino acids),
copoly(ether-esters), polyalkylenes oxalates, polyamides, tyrosine
derived polycarbonates, poly(iminocarbonates), polyorthoesters,
polyoxaesters, polyamidoesters, polyoxaesters containing amine
groups, poly(anhydrides), polyphosphazenes, biomolecules (i.e.,
biopolymers such as collagen, elastin, bioabsorbable starches,
etc.), and any blends and copolymers thereof.
[0019] For the purpose of this invention aliphatic polyesters
include, but are not limited to, homopolymers and copolymers of
lactide (which includes lactic acid, D-,L- and meso lactide),
glycolide (including glycolic acid), .epsilon.-caprolactone,
p-dioxanone (1,4-dioxan-2-one), trimethylene carbonate
(1,3-dioxan-2-one), alkyl derivatives of trimethylene carbonate,
.delta.-valerolactone, .beta.-butyrolactone, .gamma.-butyrolactone,
.epsilon.-decalactone, hydroxybutyrate, hydroxyvalerate,
1,4-dioxepan-2-one (including its dimer
1,5,8,12-tetraoxacyclotetradecane-7,14-dione), 1,5-dioxepan-2-one,
6,6-dimethyl-1,4-dioxan-2-one 2,5-diketomorpholine, pivalolactone,
.alpha., .alpha. diethylpropiolactone, ethylene carbonate, ethylene
oxalate, 3-methyl-1,4-dioxane-2,5-dione,
3,3-diethyl-1,4-dioxan-2,5-dione, 6,8-dioxabicycloctane-7-one and
polymer blends thereof. Poly(iminocarbonates), for the purpose of
this invention, are understood to include those polymers as
described by Kemnitzer and Kohn, in the Handbook of Biodegradable
Polymers, edited by Domb, et. al., Hardwood Academic Press, pp.
251-272 (1997). Copoly(ether-esters), for the purpose of this
invention, are understood to include those copolyester-ethers as
described in the Journal of Biomaterials Research, Vol. 22, pages
993-1009, 1988 by Cohn and Younes, and in Polymer Preprints (ACS
Division of Polymer Chemistry), Vol.30(1), page 498, 1989 by Cohn
(e.g., PEO/PLA). Polyalkylene oxalates, for the purpose of this
invention, are understood to include those described in U.S. Pat.
Nos. 4,208,511; 4,141,087; 4,130,639; 4,140,678; 4,105,034; and
4,205,399. Polyphosphazenes, co-, ter- and higher order mixed
monomer based polymers made from L-lactide, D,L-lactide, lactic
acid, glycolide, glycolic acid, para-dioxanone, trimethylene
carbonate and .epsilon.-caprolactone are understood to be those as
are described by Allcock in The Encyclopedia of Polymer Science,
Vol. 13, pages 31-41, Wiley lntersciences, John Wiley & Sons,
1988 and by Vandorpe, et al in the Handbook of Biodegradable
Polymers, edited by Domb, et al., Hardwood Academic Press, pp.
161-182 (1997). Polyanhydrides are understood to include those
derived from diacids of the form
HOOC--C.sub.6H.sub.4--O--(CH.sub.2).sub.m--O--C.sub.6H.sub.4--COOH,
where "m" is an integer in the range of from 2 to 8, and copolymers
thereof with aliphatic alpha-omega diacids of up to 12 carbons.
Polyoxaesters, polyoxaamides and polyoxaesters containing amines
and/or amido groups are understood to be those as described in one
or more of the following U.S. Pat. Nos. 5,464,929; 5,595,751;
5,597,579; 5,607,687; 5,618,552; 5,620,698; 5,645,850; 5,648,088;
5,698,213; 5,700,583; and 5,859,150. Finally, polyorthoesters are
understood to be those as described by Heller in Handbook of
Biodegradable Polymers, edited by Domb, et al., Hardwood Academic
Press, pp. 99-118 (1997).
[0020] Exemplary bioabsorbable materials include, but are not
limited to, polygylcolic acid, polylactic acid, and polyethylene
oxide, and blends and copolymers thereof. Alternatively, inorganic
materials can be used to form the abrasive particles, such as, for
example, tricalcium phosphate.
[0021] The resulting abrasive particles can be any size which
allows for effective cutting of the hard material, while at the
same time does not deteriorate the nozzle of the high pressure
fluid jet. In an one embodiment, the abrasive particles can have a
size in the range of about 5 microns to 200 microns, depending upon
when the abrasive particles are mixed with the pressurized stream
of fluid. For example, if the abrasive particles are mixed with the
high pressure jet prior to the high pressure jet flowing through
the nozzle, the abrasive particles can be sized so as not to clog
or diminish the performance of the nozzle. Thus, in an exemplary
embodiment, the abrasive particles may be sized substantially
smaller than the size of the nozzle, such as, for example, in the
range of about 5 microns to 20 microns. Alternatively, for
applications involving mixing the abrasive particles after the high
pressure jet leaves the nozzle, where clogging or diminishing the
performance of the nozzle is not as great of a concern, the
particles can be a variety of sizes, such as, for example, in the
range of about 5 microns to 200 microns.
[0022] While virtually any type of high pressure fluid jet system
can be used with the various embodiments disclosed herein, the
system generally includes a drive mechanism and a fluid source.
While the fluid source can utilize a variety of fluids that can
safely be delivered into the human body, in an exemplary
embodiment, the fluid is saline. Further, the fluid can flow
through the system at various rates depending upon the type of
material desired to be cut, however the pressure of the stream of
fluid is generally in the range of about 5 to 50,000 psi, more
preferably in a range of about 1,000 to 20,000 psi, and most
preferably in a range of about 5,000 to 15,000 psi. Following the
combination of the abrasive materials and delivery liquid with the
pressurized stream of fluid, the concentration of abrasive
materials within the pressurized stream of fluid is generally no
more than about 30% by volume, and more preferably in the range of
about 5%-20% by volume.
[0023] FIG. 1A illustrates one exemplary embodiment of a high
pressure fluid jet system 10 that is useful to cut hard materials
in a surgical procedure by combining particles of an abrasive
material with a stream of pressurized fluid. As shown, the system
10 can include a fluid source 20, such as a saline, that is in
fluid communication with a drive mechanism 16. The drive mechanism
16 communicates the fluid to a suspension pump drive mechanism 31
such that a concentrated suspension of abrasive particles and
delivery liquid, such as saline, (the "slurry") 33 can be combined
with a pressurized stream of fluid prior to the pressurized stream
of fluid entering a fluid jet delivery device or an application
tool 28. The fluid source 20 can be coupled to the drive mechanism
16 using a variety of techniques, but in one exemplary embodiment
the fluid source 20 includes a conduit 26 (discussed in more detail
below) that extends between the fluid source 20 and the drive
mechanism 16. Likewise, the drive mechanism 16, the suspension pump
drive mechanism 31, and the application tool 28 can also be
connected by a conduit 26 extending therebetween. A person skilled
in the art will appreciate that the high pressure fluid jet system
can include a variety of other components, and that each component
can have a variety of configurations. Moreover, the components can
be integrally formed with one another or they can be removably
attached to one another.
[0024] While virtually any known drive mechanism 16 can be used,
the drive mechanism 16 can include a pump console 22 for pumping
fluid from the fluid source 20 through a pump cartridge (not shown)
at a controlled rate. The exemplary pump console 22 can include a
push rod that is driven by a motor disposed within the pump console
22, and that includes controls to allow a user to input the desired
pump parameters. In use, the motor is effective to reciprocate the
push rod along its axis, thereby reciprocating a piston disposed
within the pump cartridge to pump fluid through the cartridge
towards the application tool 28.
[0025] Connected to drive mechanism 16 (by conduit 26) is a
suspension pump drive mechanism 31 which delivers a concentration
of slurry 33 into the pressurized stream of fluid. The slurry can
include any combination of the abrasive materials disclosed herein
mixed or suspended within a delivery liquid, e.g., saline. However,
by way of non-limiting example, the slurry contains at least about
40% of abrasive solid particles by volume, and in a preferred
embodiment at least about 20% of abrasive solid particles by
volume. The suspension pump drive mechanism 31 is similar to the
drive mechanism 16 and, as shown in FIG. 1B, has a slurry pump
console 30 which can include a piston 40 which slidably moves
within a pump cavity 38 such that the slurry is pushed into the
pressurized stream of fluid.
[0026] The pump cavity 38 of slurry pump console 30 can have a
variety of configurations, however it generally is complementary in
shape to the piston 40 and has an inlet port 32 through which the
slurry enters the cavity 38 and an outlet 36 through which the
slurry exits the cavity to ultimately mix with the pressurized
stream of fluid. The inlet port 32 can be of any size, shape and
configuration that renders it capable of transporting the slurry.
In one embodiment, however, it is a conduit 26 (discussed in more
detail below) reversibly or integrally mated to a valve mechanism
34. A variety of valve mechanisms 34 can be used so long as they
are capable of controlling the rate and amount of slurry which
enters into the cavity 38, such as, for example, a manual valve, a
two-way valve, a one-way valve, or an automatically or
electronically controlled valve. One skilled in the art will
appreciate that the ability to control the amount of slurry
entering the cavity 38, and ultimately the application tool 28,
allows a surgeon to perform a variety of different procedures using
a variety of different abrasive materials.
[0027] While the piston 40 can have any known configuration, the
piston 40 is generally constructed so that it is able to move
within the pump cavity 38 such that the slurry is dispensed through
an outlet 36 towards the application tool. The outlet 36 can also
be of any configuration known in the art to transport the slurry,
however, by way of non-limiting example, it is an integrally formed
or removably mated conduit 26 (such as is discussed below). Once
the slurry is dispensed through the outlet 36, the piston 40 can
then retract, thereby allowing slurry to refill the pump cavity
38.
[0028] Referring back to FIG. 1A, the fluid delivery conduit 26 can
also have a variety of configurations. In one exemplary embodiment,
the fluid delivery conduit 26 can be formed from a material which
has sufficient burst strength to safely deliver fluid at a high
pressure to the application tool 28. The material should also be
flexible to enable a surgeon to manipulate the application tool 28
freely. The fluid delivery conduit 26 can also include connectors,
which in an exemplary embodiment can be hand tightened, to connect
the ends of the fluid delivery conduit 26 to the fluid source 20,
drive mechanism 16, suspension pump drive mechanism 31, and/or
application tool 28, where detachable components are desired. As
previously indicated, the fluid delivery conduit 26 can be
integrally formed with or removably mated to the fluid source 20,
drive mechanism 16, suspension pump drive mechanism 31, and/or
application tool 28.
[0029] The application tool 28 can also have a variety of
configurations, and virtually any device for forming a high
pressure fluid jet can be used with the various embodiments
disclosed herein. For example, the application tool 28 can include
a lumen in fluid communication with the delivery conduit 26 and a
nozzle for forming a high pressure fluid jet. The application tool
28 can also include an evacuation lumen for collecting and
withdrawing fluid, as well as a variety of other features for
facilitating use of the device. By way of non-limiting example, one
exemplary embodiment of a fluid jet device is disclosed in commonly
owned U.S. patent application Ser. No. 10/904,456 filed on Nov. 11,
2004 and entitled "Methods and Devices for Selective Bulk Removal
and Precision Sculpting of Tissue" by McRury et al.
[0030] FIG. 2 illustrates another embodiment of the present
invention in which abrasive particles are entrained in a
pressurized stream of fluid 114 after the fluid exits a nozzle 128
of an application tool or fluid jet delivery device. As shown, a
second, collimating nozzle 131 surrounds the nozzle 128 of the
application tool and forms a cavity 129 which maintains the slurry
around the nozzle so that when the pressurized stream of fluid 114
enters the cavity 129, some of the abrasive particles in the slurry
become entrained within it, and the abrasive-containing pressurized
stream of fluid exits the cavity 129 through opening 125.
[0031] While the collimating nozzle 131 can have a variety of
shapes, in one embodiment the collimating nozzle 131 has a shape
which complements the shape of the nozzle 128 of the application
tool. The collimating nozzle 131 can also have an inlet port 127
which allows for the entry of the slurry into the cavity 129, and
in a preferred embodiment, the inlet port 127 includes a conduit
(not shown) which is connected to a large supply of the
concentrated slurry.
[0032] While the cavity 129 can be a variety of shapes, as shown,
the cavity 129 is complementary to the shape of the collimating
nozzle 131. The cavity 129 further can be a variety of sizes,
however it should be large enough to maintain a presence of slurry
around the nozzle 128 of the application tool. In use, once the
cavity 129 is filled with slurry, the pressurized stream of fluid
114 flows into the cavity 129 via the nozzle 128. The influx of the
pressurized stream of fluid 114 into the cavity 129 creates suction
or a vacuum within the cavity 129, and, as a result, the slurry
becomes entrained with the pressurized stream of fluid 114. The
abrasive-containing pressurized fluid stream exits opening 125 in
the collimating nozzle 131, and can then be used to cut hard
material upon contact. One skilled in the art will appreciate that
this embodiment provides the option of on-demand control to engage
and/or disengage the flow of the abrasive material.
[0033] FIGS. 3-4B illustrate alternative embodiments of the present
invention in which the pressurized fluid stream can erode a
suspension or solid form of the abrasive material resulting in the
abrasive solid particles becoming entrained within the pressurized
stream of fluid. Referring first to FIG. 3, the pressurized stream
of fluid 214 flows out of the nozzle 228 of the high pressure jet
212 and contacts a supply 211 which contains the abrasive material.
Once the pressurized stream of fluid contacts the supply 211, a
portion of the abrasive material is eroded, resulting in abrasive
particles becoming entrained within the pressurized stream of fluid
214 such that hard material 200 can be cut upon contact.
[0034] One skilled in the art will appreciate that the supply 211
of abrasive material can be a variety of forms, depending upon the
type of material used. In exemplary embodiments, the supply 211 can
be a solid which is rod-shaped (as shown), cylindrical, or any
other shape, or a suspension. Further, the supply 211 can have any
configuration which can hold the abrasive material, such as, for
example, a conduit. The supply 211 can be directed to the
pressurized fluid stream 214 in a variety of ways, however, in an
exemplary embodiment it is cross-fed into the pressurized fluid
stream 214. One skilled in the art will further appreciate that
this embodiment requires a very short residence time of the
abrasive before it is delivered to the hard material, so that
abrasive materials other than those mentioned above, such as
crushed ice, may be used.
[0035] FIGS. 4A-4B illustrate an alternative embodiment of the
present invention in which the pressurized stream of fluid 214
erodes a portion of a cutting template 257 placed on the hard
material 200. The cutting template 257 can be any form which allows
for hard material to be cut in a desired pattern, however, by way
of non-limiting example, the template 257 can have a solid region
262 and an open region 260, as shown in FIG. 4B. The solid region
262 can be made of any biocompatible material such as a metal
(e.g., stainless steel) or a polymer (e.g., high density
polyethylene or Polyetherether Ketone (PEEK)), or any other
material that will not erode when contacted by the pressurized
stream of fluid. The solid region 262 can also be a variety of
shapes, such as a plate or a cartridge, so long as the shape can
contain within it an open region or cutting region (such as open
region 260, for example) having an agglomerate of abrasive
material. The open region 260 can be formed from any occlusion of
the abrasive materials listed herein and can be a variety of shapes
depending upon the type of cut desired by the surgeon, such as a
line, a plug, a circle, etc., however as shown the open region 260
is a crescent shape.
[0036] In use, as shown in FIG. 4A, the pressurized stream of fluid
214 flows out of the nozzle 228 of the high pressure jet 212 and
contacts the template 257. Upon contact, the abrasive material in
the open region 260 is eroded by the pressurized stream of fluid
214, resulting in abrasive particles becoming entrained within the
pressurized stream of fluid 214 while the solid region 262 remains
unchanged. As a result, the hard material 200 is cut in a pattern
which complements the pattern of the open region 260. One skilled
in the art will appreciate that because the solid region 262 does
not erode upon contact with the pressurized stream of fluid 214, it
can be reused.
[0037] One skilled in the art will further appreciate further
features and advantages of the invention based on the
above-described embodiments. Accordingly, the invention is not to
be limited by what has been particularly shown and described,
except as indicated by the appended claims. All publications and
references cited herein are expressly incorporated herein by
reference in their entirety.
* * * * *