Note: Descriptions are shown in the official language in which they were submitted.
CA 022~2798 1998-10-27
W O 98/37819 PCTAUS98/03580
PREVENTING REUSE OF SURGICAL DEV~CES
FIELD OF THE INVENTION
The present invention generally relates to ultrasonic devices.
S More particularly, the present invention relates a disposable, single useultrasonic surgical instrument or tool. In one embodiment, the instrument
includes a component that distorts if the instrument is resterilized, thus
preventing reuse of the instrument. In an all~lnaLi~e arrangement,
sterilization of the instrument inhibits the ultrasonic tr~ncmi.~.~ion capabilities
of the instrument, thus preventing reuse.
BACKGROUND OF THE INVENTION
Ultrasonic tr~n~mic~ion devices are well known for use in a
variety of applications, such as surgical operations and procedures. The
ultrasonic tr~n~mi~sion devices usually include a transducer that converts
electrical energy into vibrational motion at ultrasonic frequencies. The
vibrational motion is usually transmitted to vibrate a distal end of a surgical
instrument.
The ultrasonic surgical instrument may be used to, for example,
dissect or cut living organic tissue. The dissecting or cutting action is
accomplished by an end effector at the distal end of the insLlul~lent, the end
effector tr~n~mitting ultrasonic energy to the tissue. The ultrasonic energy
may be used to cauterize tissue sullou,lding the end effector, causing
hemostasis by coagulating blood in the ~u~loul~ding tissue.
After a physician uses the surgical in~l~un~enL in an operation,
the surgical il~sl~ ent may be resterilized and reused. However, the
surgical insLIu~ent may not be suitable for resterilization. Purthermore,
resterilizing the surgical instrument may not be effective, increasing the risk
of spreading various (lice~es. In addition, resterilization may be time
co~ .i.,g and expensive.
CA 022~2798 1998-10-27
W O 98/37819 PCTAUS98/03S80
Surgical instruments have been developed to be disposed of
after an initial use to reduce the potential for the tr~ncmicsion of various
diseases. Typically, these devices rely on user adherence to the device
labeling to prevent reuse. For example, a label may be attached to a surgical
instrument warning "single use only". However, even with the proliferation
of such warnings, the admonitions are often ignored. In addition, users may
re-sterilize and reuse single use surgical instruments despite the fact that theresterilization may not be successful and the instrument may not be suitable
for multiple uses.
Accordingly, there exists a need for a disposable, single use
surgical instrument. It would be beneficial if the surgical instrument could
prevent re-use of the instrument and warn medical personnel that the
instrument should not be reused. It would also be desirable to provide a
surgical illsllulllent which is sufficiently economical in its construction.
Sl~MMARY OF THE INVENTION
In view of the above, the present invention provides a surgical
instrument that is disposable after a single use. The surgical- illsllùlllent isrelatively simple in construction, economical to m~m-facture, and effective
for preventing reuse of the surgical insllulllent. The surgical instrument
elimin~tes time col~ g and costly resterilization techniques.
A temperature sensitive component or material can be coupled
to the surgical i~ lulllent. The component can be initially commercially
sterilized, but the component distorts, expands, or melts upon resterilization
or exposure to a change in the lelll~elature, thereby preventing reuse of the
surgical instrument. The distortion of the component can alert medical
personnel that the surgical ill~llulll~llL should not be used again. Since the
surgical instrument may not be reused, the risk of tr~ncmiccion of infectious
~i~e~es is reduced or lessened.
.. ~ , .
CA 022~2798 1998-10-27
W O 98/37819 PCT~US98/03S80
An ultrasonic surgical device in accordance with the present
invention includes a tr~n.c~llcer assembly adapted to vibrate at an ultrasonic
frequency in response to electrical energy. A ~ liCcion rod is adapted to
receive ultrasonic vibration from the tr~nc~llcer assembly and to transmit the
5 ultrasonic vibration from a first end to a second end of tne tr~ncmi.ssion rod.
A sheath surrounds at least a portion of the tr~ncmiccion rod and includes a
l~lnl)eldt7~re sensitive material that distorts when exposed to heat. An end
effector is adapted to receive the ultrasonic vibration from the tran.cmi.csion
rod and to transmit the ultrasonic vibration from a first end to a second end
10 of the end effector. The second end of the end effector is disposed near an
antinode and the first end of the end effector coupled to the second end of the
tr~ncmicsion rod.
A single use ultrasonic surgical device in accordance with the
present invention includes a tr~n.cmi.c.sion component adapted to receive
15 ultrasonic vibration from a tr~nc~ cer assembly and to transmit the ultrasonic
vibration from a first end to a second end. A hub is coupled to the
",i.ccion component and includes a temperature sensitive material that
distorts when exposed to heat.
It is to be understood that both the foregoing general
20 description and the following detailed description are exemplary and
explanatory and are inten(lecl to provide further explanation of the invention
as c!~im~(l.
The invention, together with ~tt~n-~nt advantages, will best be
understood by reference to the following detailed description of the preferred
25 emb~lim~llt.c of the invention, taken in conjunction with the accompanying
~ drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a cutaway view and in partial cross-section of an
30 emb~im~nt of a surgical system in accordance with the present invention;
CA 022~2798 1998-10-27
W O 98/37819 PCT~US98/03580
FIG.2is a cross-sectional view of a surgical instrument of the
surgical system of FIG. 1 taken about line 2-2;
FIG.3is a perspective view of a handpiece assembly of the
surgical system of FIG. l;
FIG.4is a perspective view of ~e surgical instrument of the
surgical system of FIG. l;
FIG.Sis an exploded view of the surgical instrument of
FIG. 4;
FIG.6is a partial cutaway perspective view of the surgical
10instrument of FIG.3;
FIG.7is a partial cross-sectional view of another embodiment
of the surgical instrument of FIG. 4 having an outer sheath of surgical
instrument removed;
FIG.8is a partial perspective view of another embodiment of
15the surgical instrument of FIG.3 with the outer sheath removed;
FIG.9is a partial cross-sectional view of a hub of the surgical
instrument of FIG.4;
FIG. lOis a partial cross-sectional view of another embodiment
of the hub of the surgical instrument of FIG.4;
FIG.llis a partial cross-sectional view of the hub of FIG. 9
after the hub has been exposed to heat;
FIG. 12is a perspective view of a wrench configured to tighten
an surgical in~ melll to a handpiece assembly;
FIG.13is a partial perspective view of another embodiment of
25the surgical in~ llent of FIG.3; and
FIG.14is a cross-sectional view of the surgical instrument of
FIG. 13 taken about line 14.
CA 022~2798 1998-10-27
W O 98/37819 PCTAJS98/03580
DESCRIPTION OF TH~ PREFERRED EMBODIMENTS
Before explaining the present invention in detail, it should be
noted that the invention is not limited in its application or use to the details of
construction and arrangement of parts illustrated in the accompanying
5 drawings and description, because the illustrative embodiments of the
invention may be implemented or incorporated in other embodiments,
variations and modifications, and may be practiced or carried out in various
ways. Furthermore, unless otherwise in~ te~, the terms and expressions
employed herein have been chosen for the purpose of describing the
- 10 illustrative embodiments of the present invention for the convenience of the
reader and are not for the purpose of limiting the invention.
Referring now to FIG. 1, a presently preferred embodiment of
the surgical system 10 is illustrated. The surgical system 10 generally
includes a generator 30, a handpiece assembly 50, an acoustic or tr~n~mi~sion
assembly 80, an adapter 120, and a surgical instrument or a sheath blade
system 150. The generator 30 sends an electrical signal through a cable 32
at a selected amplitude, frequency, and phase detelllfined by a control system
of the generator 30. As will be further described, the signal causes one or
more piezoelectric elements of the acoustic assembly 80 to expand and
20 contract, thereby converting the electrical energy into mechanical motion.
The mec-h~ni~l motion results in longit l~in~l waves of ultrasonic energy that
propagate through the acoustic assembly 80 in an acoustic st~n~ing wave to
vibrate the acoustic assembly 80 at a selected frequency and amplitude. An
end effector 88 at the distal end of the acoustic assembly 80 is placed in
25 contact with tissue of the patient to transfer the ultrasonic energy to the
tissue. The cells of the tissue in contact with the end effector 88 of the
acoustic assembly 80 will move with ~e end effector 88 and vibrate.
As the end effector 88 couples with the tissue, thermal energy
or heat is generated as a result of internal cellular friction within the tissue.
30 The heat is sufficient to break protein hydrogen bonds, c~llsing the highly
CA 022~2798 1998-10-27
W O 98/37819 PCTAUS98/03580
structured protein (i.e., collagen and muscle protein) to denature (i.e.,
become less or~ni7e~). As the proteins are denatured, a sticky coagulum
forms to seal or coagulate small blood vessels when the coagulum is below
100~C. Deep coagulation of larger blood vessels results when the effect is
prolonged.
The transfer of the ultrasonic energy to the tissue causes other
effects including mech~nic~l tearing, cutting, cavitation, cell disruption, and
emulsification. The amount of cutting as well as the degree of coagulation
obtained varies with the vibrational amplitude of the end effector 88, the
amount of pressure applied by the user, and the sharpness of the end effector
88. The end effector 88 of the acoustic assembly 80 in the surgical system
10 tends to focus the vibrational energy of the system 10 onto tissue in
contact with the end effector 88, intensifying and loc~li7.ing thermal and
In~c'n~nir~l energy delivery.
As illustrated in FIG. 1, tne generator 30 includes a control
system integral to the generator 30, a power switch 34, and a triggering
m~ch~ni~m 36. The power switch 34 controls the electrical power to the
generator 30, and when activated by the triggering mech~nicm 36, the
generator 30 provides energy to drive the acoustic assembly 80 of the
surgical system 10 at a predetermined frequency and to drive the end effector
88 at a predete~ ed vibrational amplitude level. The generator 30 may
drive or excite the acoustic assembly 80 at any suitable resonant frequency of
the acoustic assembly 80.
When the geneldlur 30 is activated via the triggering
mech~nicm 36, electrical energy is continuously applied by the genelalol 30
to a tr~n~ cer assembly 82 of the acoustic assembly 80. A phase locked
loop in the control system of the generator 30 monitors feedback from the
acoustic assembly 80. The phase lock loop adjusts the frequency of the
electrical energy sent by the gel.e~ator 30 to match a preselected harmonic
frequency of the acoustic assembly 80. In addition, a second feedback loop
. .
CA 022~2798 1998-10-27
WO 98/37819 PCTAJS98/03580
in the control system m~int~in~ the electrical current supplied to the acoustic
assembly 80 at a preselected constant level in order to achieve substantially
constant vibrational amplitude at the end effector 88 of the acoustic assembly
80.
The electrical signal supplied to the acoustic assembly 80 will
cause the distal end to vibrate longit~-1in~lly in the range of, for example,
approximately 20 kHz to 100 kHz, and preferably in the range of about 54
kHz to 56 kHz, and most preferably at about 55.5 kHz. The amplitude of
the acoustic vibrations at the end effector 88 may be controlled by, for
example, controlling the amplitude of the electrical signal applied to the
tr~n.~hlcer assembly 82 of the acoustic assembly 80 by the generator 30.
As noted above, the kiggering mech~ni~m 36 of the generator
30 allows a user to activate the generator 30 so that electrical energy may be
continllously supplied to the acoustic assembly 80. In one embodiment, the
triggering mechanism 36 preferably comprises a foot activating switch that is
~h~hly coupled or attached to the generator 30 by a cable or cord. In
another embodiment, a hand switch may be incorporated in the handpiece
assembly 50 to allow the generator 30 to be activated by a user.
The generator 30 also has a power line 38 for insertion in an
electrosurgical unit or conventional electrical outlet. lt is contemplated that
the generator 30 may also be powered by a direct current (DC) source, such
as a battery. The generator 30 may be any suitable generator, such as Model
No. GENO1, available from Ethicon Endo-Surgery, Inc.
Referring to FIGS. 1 and 3, the handpiece assembly 50 of the
surgical system 10 includes a multi-piece housing or outer casing 52 adapted
to isolate the operator from the vibrations of the acoustic assembly 80. The
housing 52 is preferably cylindrically shaped and is adapted to be held by a
user in a conventional manner, but may be any suitable shape and size which
allows it to be grasped by the user. While a multi-piece housing 52 is
illustrated, the housing 52 may comprise a single or unitary component.
-
CA 022~2798 1998-10-27
W O 98/37819 PCTAJS98/03580
The housing 52 of the handpiece assembly 50 is preferably
constructed from a durable plastic, such as Ultem~. It is also contemplated
that the housing 52 may be made from a variety of materials including other
plastics (i.e. Iiquid crystal polymer (LCP), nylon, or polycarbonate). A
suitable handpiece assembly 50 is Model No. HP050, available from Ethicon
Endo-Surgery, Inc.
Referring now FIG. 1, the handpiece assembly 50 generally
includes a proximal end 54, a distal end 56, and centrally disposed axial
opening or cavity 58 extending longit~-lin~lly therein. The distal end 56 of
the handpiece assembly 50 includes an opening 60 configured to allow the
acoustic assembly 80 of the surgical system 10 to extend thele~lrough, and
the proximal end 54 of the handpiece assembly 50 is coupled to the generator
30 by a cable 32. The cable 32 may include ducts or vents 62 to allow air to
be introduced into the handpiece assembly 50 to cool the transducer assembly
82 of the acoustic assembly 80.
As shown in FIG. 1, the acoustic assembly 80 generally
includes a tr~nc~rer stack or assembly 82 and a ~l~"cll,icsion component or
working member. The tr~ncmi.csion component may include a mounting
device 84, a tr~ncmicsion rod or waveguide 86, and an end effector or
applicator 88. The tr~ncmi.csion rod 86 and end effector 88 are preferably
part of the surgical instrument 150 as furtner described below.
The components of the acoustic assembly 80 are preferably
acoustically tuned such that the length of each component is an integral
number of one-half system wavelengths (n~/2) where the system wavelength
~ is the wavelength of a preselected or operating longitl~lin~l vibration
frequency f of the acoustic assembly 80. It is also contemplated that the
acollstic assembly 80 may incorporate any suitable arrangenle,lt of acoustic
elements. For example, the acoustic assembly 80 may comprise a transducer
assembly and an end effector (i.e., the acoustic assembly 80 may be
configured without a mounting device and a tr~ncmiccion rod).
... .
CA 022~2798 1998-10-27
W O 98/37819 PCTAUS98/03580
The tr~n~ cer assembly 82 of the acoustic assembly 80
converts the electrical signal from the generator 30 into mechanical energy
that results in longit~-1in~1 vibratory motion of the end effector 88 at
ultrasonic frequencies. When the acoustic assembly 80 is energized, a
S vibratory motion st~n-lin~ wave is generated through the acoustic assembly
80. The amplitude of the vibratory motion at any point along the acoustic
assembly 80 depends on the location along the acoustic assembly 80 at which
the vibratory motion is measured. A lI~illill~ll~l or zero crossing in the
vibratory motion st~n-ling wave is generally referred to as a node (i.e., where
axial motion is usually minim~l and radial motion is usually small), and an
absolute value m~ximl1m or peak in the standing wave is generally referred to
as an antinode. The distance between an antinode and its nearest node is
one-quarter wavelength (~/4).
As shown in FIG. 1, the transducer assembly 82 of the acoustic
assembly 80, which is known as a "Langevin stack", generally includes a
tr~n~dllction portion 90, a first resonator 92, and a second resonator 94. The
tr~ncdllcer assembly 82 is preferably an integral number of one-half system
wavelengths (n~/2) in length. It is to be understood that the present
invention may be alternatively configured to include a transducer assembly
comprising a magnetostrictive, electromagnetic or electrostatic transducer.
The distal end of the first resonator 92 is connected to the
proximal end of transduction section 90, and the proximal end of the second
resonator 94 is connPcte~l to the distal end of transduction portion 90. The
first and second resonators 92 and 94 are preferably fabricated from titanium,
iqlm~ l, steel, or any other suitable material. The first and second
resonators 92 and 94 have a length detell-~ined by a number of variables,
inrh~ding the thic~nPss of the transduction section 90, the density and
modulus of elasticity of material used in the resonators 92 and 94, and the
f~ln~mental fre~uency of the tr~n~ cer assembly 82. The second resonator
. . , ~ .
CA 022~2798 1998-10-27
W O 98/37819 PCT~US98/03580
- 10 -
94 may be tapered inwardly from its proximal end to its distal end to amplify
the ultrasonic vibration amplitude.
The tr~n~luction portion 90 of the tr~n~d~lcer assembly 82
preferably comprises a piezoelectric section of alternating positive electrodes
96 and negative electrodes 98, with piezoelectric elements 100 allellla~ g
between the electrodes 96 and 98. The piezoelectric elements 100 may be
fabricated from any suitable material, such as, for example, lead zirconate-
titanate, lead meta-niobate, lead titanate, or ceramic piezoelectric crystal
material. Each of the positive electrodes 96, negative electrodes 98, and
10 piezoelectric elements 100 may have a bore exterl-ling through the center.
The positive and negative electrodes 96 and 98 are electrically coupled to
wires 102 and 104, respectfully. The wires 102 and 104 transmit the
electrical signal from the generator 30 to electrodes 96 and g8.
As illustrated in FIG. 1, the piezoelectric elements 100 are held
lS in compression between the first and second resonators 92 and 94 by a bolt
106. The bolt 106 preferably has a head, a shank, and a threaded distal end.
The bolt 106 is inserted from the proximal end of the first resonator 92
through the bores of the first resonator 92, the electrodes 96 and 98, and
piezoelectric elements 100. The threaded distal end of the bolt 106 is
screwed into a threaded bore in the proximal end of second resonator 94.
The piezoelectric elem~nt~ 100 are energized in response to the
electrical signal supplied from the generator 30 to produce an acoustic
st~n-ling wave in the acoustic assembly 80. The electrical signal causes
disturbances in the piezoelectric elements 100 in the form of repeated small
displacements res~ ing in large co.llpression forces within the material. The
repeated small displacements cause the piezoelectric elements 100 to expand
and contract in a continuous manner along the axis of the voltage gradient,
producing high frequency longi~ in~l waves of ultrasonic energy. The
ultrasonic energy is Ll~"~",il~(l through the acoustic assembly 80 to the end
effector 88.
_ ~ ... . .. . . . . . .... . .
CA 022~2798 1998-10-27
W O 98/37819 PCTAJS98/03580
The mounting device 84 of the acoustic assembly 80 has a
proximal end, a distal end, and may have a length substantially equal to an
integral number of one-half system wavelengths. The proximal end of the
mounting device 84 is preferably axially ~lign~d and coupled to the distal end
of the second resonator 94 by an internal threaded connection near an anti-
node. (For purposes of this disclosure, the term "near" is defined as "exactly
at" or "in close proximity to".) It is also contemplated that the mounting
device 84 may be attached to the second resonator 94 by any suitable means,
and the second resonator 94 and mounting device 84 may be formed as a
single or unitar,v component.
The mounting device 84 is coupled to the housing 52 of the
handpiece assembly 50 near a node. The mounting device 84 may include an
integral ring 108 disposed around its periphery. The integral ring 108 is
preferably disposed in an annular groove 110 formed in the housing 52 of the
handpiece assembly 50 to couple the mounting device 84 to the housing 58.
A compliant member or material 112, such as a pair of silicone rubber O-
rings attached by stand-offs, may be placed between the ~nmll~r groove 110
of the housing 52 and the integral ring 108 of the mounting device 86 to
reduce or prevent ultrasonic vibration from being tr~n.cmitted from the
mounting device 84 to the housing 52.
The mounting device 84 may be secured in a predet~ ined
axial position by a plurality of pins 114, preferably four. The pins 114 are
disposed in a longih~ n~1 direction 90 degrees apart from each other around
the outer periphery of the mounting device 84. The pins 114 are coupled to
the housing 52 of the handpiece assembly 50 and are disposed through
notches in the integral ring 108 of the mounting device 84. The pins 114 are
preferably fabricated from stainless steel.
The mo~ ting device 84 is preferably configured to amplify the
ultrasonic vibration amplitude that is l~A~ e~l through the acoustic
assembly 80 to the distal end of the end effector 88. In one preferred
"
CA 022~2798 1998-10-27
W O 98/37819 PCTAUS98/03580
emb~ime~t the mounting device 84 comprises a solid, tapered horn. As
ultrasonic energy is L~a.ls~ d through the mounting device 84, the velocity
of the acoustic wave tr~n~mitte~l through the mounting device 84 is amplified.
It is contemplated that the mounting device 84 may be any suitable shape,
such as, for example, a stepped horn, a conical horn, an exponential horn, a
unitary gain horn, or the like.
The distal end of the mounting device 84 may be coupled to the
proximal end of the surgical instrument 150 by an internal threaded
connection. It is contemplated that the surgical instrument 150 be ~tt~ch~d to
the mounting device 84 by any suitable means. The mounting device 84 is
preferably coupled to the surgical i~ u~llelll 150.
As illustrated in FIGS. 2 and 4, the surgical instrument 150
preferably includes tr~n~micsion rod 86, end effector 88, an inner sleeve or
damping sheath 160, and an outer sheath or sleeve 170. The surgical
ins~-u~llent 150 is preferably attached to and removed from the handpiece
assembly 50 as a unit. The surgical instrument 150 is preferably Model No.
HDH05, HSH05 or HBC05, available from Ethicon Endo-Surgery, Inc.
The proximal end of the tr~n~mi~sion rod 86 of the surgical
instrument 150 is preferably det~çh~ ly coupled to the mounting device 84 of
the handpiece assembly 50 near an antinode. The ~ ",i~sion rod 86 may,
for example, have a length subs~nti~lly equal to an integer number of one-
half system wavelengths (nl\/2). The tr~n~mi~sion rod 86 is preferably
fabricated from a solid core shaft constructed out of material which
prop~g~tes ultrasonic energy efficiently, such as lilamum alloy (i.e., Ti-6Al-
4V) or an all~l"i,.u.~, alloy. It is contemplated that the l.~"~",i~sion rod 86
may be fabricated from any suitable material.
The tr~n.~mi~sion rod 86 is preferably substantially semi-
flexible. It will be recognized that the tr~n~mi~sion rod 86 may be
substantially rigid or may be a flexible wire. The ll;1"~"~icsion rod 86 may
include one or more o ~ 05illg flats and may also amplify the mechanical
CA 022~2798 1998-10-27
W O 98/37819 PCT~US98/03S80
- 13 -
vibrations L~ .C-~lilleCl through the tr~n~mi~cion rod 86 to the end effector 88as is well known in the art. The tr~n~micsion rod 86 may further have
features to control the gain of the longitu-1in~l vibration along the
tr~ncmicsion rod 86 and features to tune the tr~n~mi~sion rod to the resonant
frequency of the system.
~eferring now to FIG. 5, the tr~n~mi~sion rod 86 generally has
a first section 86a, a second section 86b, and a third section 86c. The first
section 86a of the tr~n~mi.csion rod 86 extends distally from the proximal end
of the tr~n~mi~sion rod 86. The first section 86a has a substantially
continuous cross-section dimension. The first section 86a preferably has a
radial hole or aperture 86e çxt~n-ling therethrough. The aperture 86e extends
substantially perpendicular to the axis of the trancmi~ion rod 86. The
a~ e 86e is preferably positioned at a node but may be positioned at any
other suitable point along the acoustic assembly 80. It will be recognized
that the ape,lul~ 86e may have any suitable depth and may be any suitable
shape.
The second section 86b of the tr~n~mi~sion rod 86 extends
distally from the first section 86a. The second section 86b has a substantially
continuous cross-section dimension. The diameter of the second section 86b
is smaller than the diameter of the first section 86a and larger than the
mpter of the third section 86c. As ultrasonic energy passes from the first
section 86a of the ~ i.csion rod into the second section 86b, the
narrowing of the second section 86b will result in an increased amplitude of
the ultrasonic energy passing the.el~lrough.
The third section 86c extends distally from the distal end of the
second section 86b. The third section 86c has a substantially continuous
cross-section ~limPn~ion. The third section 86c rnay also include small
meter changes along its length. As ultrasonic energy passes from the
second section 86b of the l~ ion rod 86 into the third section 86c, the
CA 022~2798 1998-10-27
W O 98/37819 PCTAJS98103580
- 14 -
narrowing of the third section 86c will result in an increased amplitude of the
ultrasonic energy passing there~lrough.
The third section 86c preferably has a plurality of grooves or
notches formed in its outer circumf~lence. Preferably, three grooves 86f,
86g, and 86h are formed in the third section 86c of the tr~n~mi~sion rod 86.
The grooves 86f, 86g, and 86h may be located at nodes of the tr~n.~mi~sion
rod 86 or any other suitable point along the transmission rod 86 to act as
~lignm~nt indicators for the installation of the damping sheath 160 and
compliant members l90a, l90b, and l90c during manufacturing. It is
contemplated that any suitable number of grooves may be formed in the
tr~n~mi~sion rod 86.
It will be recognized that the tr~n.cmi~sion rod 86 may have any
suitable cross-sectional dimension. For example, the tr~n~mi~sion rod 86
may have a substantially uniform cross-section or the tr~n~mi~.~ion rod 86
may be tapered at various sections or may be tapered along its entire length.
The distal end of the tr~n.cmi~.~ion rod 86 may be coupled to the
proximal end of the end effector 88 by an internal threaded connection,
preferably near an ~ntino~e. It is contemplated that the end effector 88 may
be attached to the tr~n.cmi~sion rod 86 by any suitable means, such as a
welded joint or the like. Although the end effector 88 may be detachable
from the tr~n~mi~sion rod 86, the end effector 88 and tr~n~mi.c~ion rod 86 are
preferably formed as a single unit.
The end effector 88 preferably has a length subst~nti~lly equal
to an integral multiple of one-half system wavelengths (n~/2). The distal end
of the end effector 88 is disposed near an antinode in order to produce the
m~ximnm longit l(lin~l deflection of the distal end. When the tr~n~ cer
assembly 82 is energized, the distal end of the end effector 88 is configured
to move longib~ n~lly in the range of, for example, approximately 10 to 500
microns peak-to-peak, and preferably in the range of about 30 to 100 microns
CA 022~2798 1998-10-27
W O 98/37819 PCT~US98/03580
at a predetermined vibrational frequency, and most preferably at about 90
microns.
The end effector 88 of the acoustic assembly 80 generally has a
first section 88a and a second section 88b. The first section 88a of the end
effector 88 extends distally from the distal end of the third section 86c of thetr~n.smi~sion rod 86. The first section 88a has a substantially continuous
cross-section dimension. The diameter of the first section 88a of the end
effector 88 is larger than the diameter of the second section 88b. The first
section 88a may also have a sealing ring 89 disposed near its distal end,
preferably near a node. As the ultrasonic energy passes from the first section
88a into the second section 88b, the m~gnit~l(le of the ultrasonic vibration
tr~n.smitted increases. It will be recognized that the end effector 88 may have
any suitable cross-section dimension.
The end effector 88 is preferably made from a solid core shaft
constructed of material such as, for example, a titanium alloy (i.e., Ti-6Al-
4V) or an al~ alloy which propagates ultrasonic energy. It is
contemplated that the end effector 88 may be fabricated from other suitable
materials. The distal end of the end effector 88 may have a surface treatment
to improve the delivery of energy and desired tissue effect. For example, the
end effector 88 may be micro-finiched, coated, plated, etched, grit-blasted,
roughened or scored to enhance coagulation in tissue or to reduce adherence
of tissue and blood to the end effector. Additionally, the distal end of the
effector 88 may be sharpened or shaped to enhance its energy tr~n~mi~ion
characteristics. For example, the end effector 88 may be blade shaped, hook
shaped, ball shaped, or any other suitable shape.
Referring now to FIGS. 5 and 6, the damping sheath 160 of the
surgical instrument 150 loosely surrounds at least a portion of the
",icsion rod 86. The damping sheath 160 may be positioned around the
"~"~icsion rod 86 to dampen or limit transverse side-to-side vibration of the
l,;1~,s",i~sion rod 86 during operation. The damping sheath 160 preferably
, .
CA 022~2798 l998-l0-27
W O 98/37819 PCTAUS98/03580
- 16 -
surrounds part of the third section 86c of the l~ c,~ ion rod 86 and is
coupled or attached to the tr~n~mi.~sion rod 86 near one or more nodes. The
damping sheath 160 iS only ~tf~rhed to the tr~n.~mi~sion rod at the nodal
points thereby preventing the sheath from otherwise adhering to the outer
surface of the tr~n~mi~sion rod 86.
In a present embodiment, the damping sheath extends along
subst~nti~lly the entire length of the tr~n~mi.~ion rod 86. The damping
sheath 160 may extend less than half the entire length of the tr~n.smission rod
86 and may be positioned around any suitable portion of the transmission rod
0 86. The sheath 160 preferably extends over at least one antinode of
transverse vibration and, more preferably, a plurality of antinodes of
transverse vibration. The damping sheath 160 preferably has a substantially
circular cross-section. It will be recognized that the damping sheath 160 may
have any suitable shape to fit over the tr~n.~mi~sion rod and may be any
suitable length.
The damping sheath 160 is preferably in light contact with the
tr~n~mi~sion rod 86 to absorb unwanted ultrasonic energy from the
tr~n.~mi~sion rod 86. The damping sheath 160 reduces the amplitude of non-
axial vibrations of the tr~n.cmi.~.~ion rod 86, such as, unwanted transverse
vibrations associated with the longihJ~lin~l frequency of 55,500 Hz as well as
other higher and lower frequencies.
The damping sheath 160 is constructed of a polymeric material,
preferably with a low coefficient of friction to minimi7e dissipation of energy
from the axial motion or longit~ in~l vibration of the tr~n.cmi.csion rod 86.
The polymeric material is preferably floura-ethylene propene (FEP) which
resists degradation when sterilized using gamma radiation. It will be
recognized that the damping sheath be fabricated from any suitable material,
such as, for example, polytetra-floura ethylene (PTFE).
The damping sheath 160 is more effective than using silicone
rubber rings located only at nodes of longihl(lin~l vibration because the
CA 022~2798 1998-10-27
W O 98/37819 PCT~US98/03580
damping sheath 160 can dampen transverse motion occurring near multiple
antinodes of the unwanted vibration which are located randomly along the
length of the tr~n~mi~sion rod 86 relative to the nodes and antinodes of the
desired longi~ in~l vibration. The damping sheath 160 can also effectively
absorb the lmw~l~ed ultrasonic energy without using a damping fluid, which
is more efficient and is advantageous in situations where the use of fluid may
be inconvenient or impractical.
Referring now to FIGS. 2, 5 and 6, the damping sheath 160
has an opening 161 extending therelhrough, one or more pairs of
diametrically opposed openings 162a, 162b, and 162c, and a longitll~lin~l slit
or slot 164. The openings 162a, 162b, and 162c are positioned over or near
the grooves 86f, 86g, and 86h of the tr~n.~mi.ccion rod 86, respectively. The
openings 162a, 162b, and 162c of the damping sheath 160 are preferably
cylindrically shaped and have a di~m~ter of about 0.078 inches. It is
contemplated that the damping sheath 160 may have any suitable number of
openings, and the openings may be any suitable shape and size without
departing from the spirit and scope of the present invention.
The length of the damping sheath 160 is preferably between
about 9.73-9.93 inches when the tr~n~mi~sion rod has a length of about 12
inches. The ~ t~nce from the proximal end of the damping sheath 160 to the
opening 162a of the damping sheath is about 0.675 inches, and the distance
from the proximal end of the damping sheath 160 to the opening 162b is
about 4.125 inches. The distance from the proximal end of the damping
sheath 160 to the oper~ing 162c is about 9.325 inches. It is collt~ )lated that
the damping sheath 160 may have any suitable length and the openings can
be at any suitable position along the damping sheath 160.
The thirknrs~ of the damping sheath 160 is preferably between
about 0.007 and 0.009, and the opening 161 (see FIG. 5) of the damping
sheath 160 has a ~i~meter between about 0.112-0.116. It is contemplated
that the thirlrn~ss of ~e damping sheath and the diameter of the opening 161
CA 022~2798 l998-l0-27
W O 98/37819 PCT/US98/03580
- 18 -
may be any suitable size without departing from the spirit and scope of the
present invention.
The slit 164 of the damping sheath 160 allows the damping
sheath 160 to be assembled over the tr~n.~mi.c.~ion rod 86 from either end.
S Without the slit 164, the sheath may not fit over the larger cross-sectional
diameters of the tr~n.cmi~sion rod 86 and the damping sheath 160 may not be
able to loosely contact the tr~n~mi.~.cion rod 86. It will be recognized that the
damping sheath 160 may have any suitable configuration to allow the
damping sheath 160 to fit over the tr~n~mission rod 86. For example, the
damping sheath 160 may be formed as a coil or spiral or may have patterns
of longit~ldin~l and/or circumferential slits or slots. It is also contemplated
that the damping sheath may be fabricated without a slit and the tr~n.cmi~sion
rod may be fabricated from two or more parts to fit within the damping
sheath.
The slit 164 of the damping sheath 160 preferably runs parallel
to the axis of the damping sheath 160 and extends from the proximal end of
the damping sheath 160 to its distal end. The widt'n of the slit 164 preferably
is about 0 to .010 inches. A center line Cs extending through the slit 164 is
preferably about 75 to 105 degrees from a center line CO extending through
the center of the openings 162a of the damping sheath 160 as illustrated in
FIG. 2. It will be recognized that the width of the slit 164 may be any
suitable size.
Referring now to FIGS. 5 and 6, the damping sheatn 160 is
coupled to or m~int~in~l on the tr~n~mi~sion rod 86 by compliant members
such as, for example, fenders or O-rings. The compliant members l90a,
l90b, and l90c may be fabricated from polymeric material, such as, for
example, silicone rubber. It will be recognized that tne compliant members
may be constructed from any suitable lllale.ial.
The compliant members 190a, l90b, and 190c are disposed
around the periphery of the damping sheath 160 and are circumferentially
.. . .. . . . . . .
CA 022~2798 l998-l0-27
W O 98/37819 PCTAJS98/03580
- 19 -
spaced from one another. The compliant members l90a, l90b, and l90c
extend across the openings 162a, 162b, and 162c of the damping sheath 160,
respectively, to allow the compliant members l90a, l90b, and l90c to be
~tt~.hed to the tr~nemiesion rod 86. The compliant members l90a, l90b,
and l90c are preferably disposed around the tr~n.emieeion rod 86 near nodes
in order to minimi7.e damping of the desired longitlldin~l vibration energy.
The compliant members l90a, 190b, and 190c are preferably
secured to the transmission rod 86 by an adhesive 196, such as, for example,
cyanoacrylate. The compliant members l90a, l90b, and l90c are joined to
the tr~n.emiesion rod 86 at the points where the openings 162a, 162b, and
162c of the damping sheath 160 allow the tr~nemieeion rod 86 to be exposed.
It is contemplated that the compliant members l90a, 190b, and 190c may be
secured to the tr~n.emi.esion rod 86 by any suitable means.
The contact between the compliant members l90a, 190b, and
l90c and the damping sheath 160 improves the damping effectiveness by
preventing large amplitude vibrations or rattling of the damping sheath 160
itself. The compliant members also prevent loss of vibrational energy from
the tr~n.emiesion rod 86 which might occur under side loading or bending
conditions which would otherwise cause indirect contact between the
tr~nemi.esion rod 86 and the outer sheath 170 through the damping sheath.
Referring now to FIG. 7, another embodiment of a damping
sheath 260 to dampen U~ ant~d vibration along a tr~nemieeion rod 286 is
illustrated. The damping sheath 260 preferably includes one or more
compliant members 280 (one being shown) and one or more sleeves 289a and
289b (two being shown). The compliant members 280 are preferably
siml-lt~n~ously created and attached to the ~ iesion rod 286 using an
insert molding process as known in the art. Each sleeve of the damping
sheath 260 is captured longitl~lin~lly between the compliant members 280 so
that the damping sheath 260 is m~int~in~d loosely in place around the
L~ .iesion rod 286. The compliant members 280 are preferably positioned
CA 022~2798 199X-10-27
W O 98/37819 PCT/US98/~3580
- 20 -
at nodes of lon~ n~l vibration of the transmission rod 286 and are
constructed of polymeric material, preferably silicone rubber. It is
coll~ell,~lated that the compliant members may be constructed of any suitable
material and may be positioned at any suitable point along the L~"c"~ ion
5 rod.
Referring now to FIG. 8, another embodiment of a damping
sheath 360 to dampen unwanted vibration along a transmission rod is
illustrated. The damping sheath 360 preferably includes at least one sleeve
or sheath 350 anchored by one or more compliant members 380a and 380b
(two being shown). The compliant members 380a and 380b are substantially
similar in construction and function as the compliant members described
above except that the compliant members 380a and 380b are created by insert
molding over the tr~n~mi~ion rod with the sleeve 350 already in place. The
sleeve 350 preferably has a pair of flanges or projections 351a and 351b
extending longinl~in~lly from each end that are captured in longitudinal slots
385a and 385b, respectfully, of the compliant members 380a and 380b.
Referring now to FIGS. 4 and 5, the outer sheath 170 of the
surgical instrument 150 surrounds the tr~n~mi~sion rod 86 and the damping
sheath 160. As shown in FIG. 5, the outer sheath 170 preferably has an
opening 171 extending longitl-~in~lly therethrough. The inside diameter of
the opening 171 is spaced at a predetermined flict~nre from the tr~n~mi~sion
rod 86 and damping sheath 160. The compliant members l90a, l90b, and
l90c are positioned between the outer sheath 170 and the damping sheath 160
to reduce the l~ "i.c~ion of vibration to the outer sheath.
The outer sheath 170 generally includes a hub 172 and an
elongated tubular member 174. The tubular member 174 may be fabricated
from stainless steel. It will be recognized that the tubular member may be
constructed from any suitable material and may be any suitable shape.
The hub 172 of the outer sheath 170 is preferably constructed
of a material which is designed to soften, melt, or otherwise deform or
~ . . .
CA 022~2798 1998-10-27
W O 98/37819 PCTn~S98/03~80
distort, when exposed to a heated environment, such as, for example, in a
steam sterilizer or autoclave. The hub 172 may be fabricated from
polycarbonate, preferably an Eastman Estalloy (DA003)
copolyester/polycarbonate alloy available from Eastman. It is contemplated
that the hub may be fabricated from any other suitable material. It will be
recognized that the hub or deformable material may be positioned at any
point along the tr~n~mi~sion rod to prevent an adapter 120 from sliding over
the surgical instrument 150 as further described below. It is also
contemplated that the adapter 120 may alternatively be configured to fit
within a hub.
The hub 172 preferably has a substantially circular cross-
section and fits snugly within the lumen 122 of the adapter 120. The snug fit
of hub within the lumen of the adapter 120 provides lateral support to the hub
172 and sheath 174 from the handpiece assembly. This protects the
tr~n~mi~sion rod 86 from bearing large forces when side loads are placed on
the surgical instrument 150. An O-ring 199 is also preferably disposed in the
hub at a node to isolate the hub 172 from the tr~n~mi~sion rod 86.
As shown in FIGS. 4 and 9, the hub 172 preferably has a pair
of holes or openings 178 on opposite sides of the hub 172 to allow the hub
172 to be coupled to the tr~n~micsion rod 86 so that the tr~n~mi~sion rod will
rotate when the hub is turned. The holes 178 of the hub 172 are aligned with
the hole 86e in the tr~n~mi~ion rod 86 to form a passageway as illustrated in
FIG. 9. A coupling member 195, such as, for example, a pin, may be
positioned within the passageway. The coupling member 195 may be held in
the passageway of the l~ "~i~sion rod 86 and hub 172 by any suitable
means, such as, for example, an cyanoacrylate adhesive, or the coupling
member may be ~et~h~hle from the tr~n~mi~ion rod 86 and hub 172. The
coupling member 195 allows rotational torque applied to the hub 172 of the
outer sheath 170 to be l~ illr~ to the tr~n~mi.~sion rod 86 in order to
tighten it onto the mounting device of the handpiece assembly 50. The
CA 022~2798 1998-10-27
W O 98/37819 PCT~US98/03S80
coupling member 195 may also hold the outer sheath 170 in place with
respect to the tr~n.cmi.~.cion rod 86.
As illustrated in FIG. 4, the hub 172 of the outer sheath 170
includes wrench flats 176 on opposites sides of the hub 172. The wrench
flats 176 are preferably formed near the distal end of the hub 172. The
wrench flats 176 of the hub 172 allow torque to be applied to the hub 172 to
tighten the tr~n~mi.csion rod 86 mounting device of the handpiece assembly.
The coupling member 195 may be vibrationally isolated from
the tr~n.cmi~.cion rod 86. As shown in FIG. 9, a compliant or isolation
member 197 surrounds the coupling member l9S. The compliant member
197 may be a thin silicone rubber layer, a sleeve of silicone rubber, or any
other suitable compliant material. The compliant member 197 prevents
con~ ction of vibration from the tr~n.~mi~sion rod 86 to the coupling member
195. As a result, the compliant member 197 prevents audible noise and
power loss from the vibration of the coupling member 195. The compliant
member 197 is preferably thin enough so that torque can be applied from the
outer sheath 170 to rotate the tr~n~mi~sion rod 86.
lt will also be recognized that the coupling member and a
compliant cushion can be permanently attached to the surgical instrument, as
described above, and such that the coupling member extends radially beyond
the outside ~ .n~lel of the tr~n~mi~sion rod, to allow the coupling member to
engage an integral or a separate and removable wrench handle.
Referring now to FIG. 10, another embodiment of a hub of a
surgical insL~ ent 450 is illustrated. The surgical i~ ument 450 is
s~lbst~nti~lly similar to the construction and function of the surgical
instrument lS0 described above except that a compliant member 460 is
formed within an aperture or passageway 462 of the tr~n.cmi.csion rod. The
compliant member 460 is preferably insert m-)l(le(l over the tr~n~mi~sion
member and extends ~rough the a~ ule through the ~ sion rod to
reduce the ~ icsiQn of vibration from the l~ sion rod to the coupling
~ . .
CA 022~2798 1998-10-27
W O 98/37819 PCTAJS98/03580
member 470. The compliant member 460 may be formed with shoulders
480a and 480b between a hub 490 of a sheath and the tr~n.cmi~ion rod to
support against radial movement of the tr~n~mi.csion rod versus the hub.
The coupling member may also be attached to a tool, such as,
for example, a wrench, so that a user may insert the coupling member into
an aperture of the lli~".~ ion rod of the surgical instrument in order to
- tighten it to the handpiece assembly. As shown in FIG. 12, a wrench handle
500 may be used to tighten a surgical instrument 510 onto a handpiece
assembly. The wrench handle 500 preferably has a coupling member 502,
- 10 such as a pin, attached thereto. The surgical instrument 510 is substantially
similar in construction and function of the surgical instrument 510 except that
the hub 512 may not have wrench flats.
The coupling member 502 is inserted through a hole or
aperture 520 that extends through an upper portion of the hub 572 and into
an aperture of the tr~n~mi.csion rod. Torque may then be applied to the
tr~n~mi.csion rod via the wrench handle 500. After torque is applied, the
wrench handle 500 may be removed from the surgical instrument 510 prior to
activating the device. Accordingly, the coupling member 502 may not have a
compliant member or coating since it is not ~tt~rh~d during ultrasonic
actuation. It is also contemplated that a torque limiting device may be
incorporated into the wlench handle 500. For example, U.S. 5,507,119 and
5,059,210, which are herein incorporated by reference, disclose torque
wrenches for att~ching and rlet~rhin~ a llA~ sion rod to a handpiece
assembly.
Referring now to FIGS. 1~, the procedure to attach and detach
the surgical instrument 150 from the handpiece assembly 50 will be described
below. When the physician is ready to use the surgical illsllulllent, the
physician simply ~tt~rh~s the surgical hlsllulllent 150 onto the handpiece
assembly. To attach the surgical instrument 150 to a handpiece assembly 50,
the distal end of the mounting device 84 is threadedly connectecl to the
.
CA 022~2798 1998-10-27
W O 98/37819 PCT~US98/03580
- 24 -
proximal end of the L~ s"~i.c~ion rod 86. The surgical instrument 150 is then
m~nll~lly rotated in a conventional screw-threading direction to interlock the
threaded connection between the mounting device 80 and the tl~"~ sion rod
86.
Once the tr~n~mi~sion rod 86 is threaded onto the mounting
device 84, a tool, such as, for example, a torque wrench, may be placed over
the surgical instrument 150 to tighten the tr~ .ic~ n rod 86 to the mounting
device 84. The tool may be configured to engage the wrench flats 176 of the
hub 172 of the outer sheath 170 or the tool may have a coupling member or
pin that is inserted into a hole or aperture 86e of the tr~n~mi~sion rod in
order to tighten the tr~n~mi~sion rod 86 onto the mounting device 84. As a
result, the rotation of the hub 172 will rotate the L~ ni~sion rod 86 until the
~l;.n~",i~sion rod 86 is tightened against the mounting device 84 at a desired
and predeLell-lilled torque.
When the tr~n~mi~ion rod 86 of the surgical instrument 150 is
attached to the mounting device 84 of the handpiece assembly 50, the
junction between the ~ ",i~ion rod 86 and the mounting device 84
produces a relatively high axial compression force that is substantially
uniformly distributed symmetrically about the longihl-lin~l axis of the
threaded connection of the mounting device and tran~mi~sion rod 86 to
efficiently transfer mechanical or ultrasonic vibrations across the junction.
As a result, the ultrasonic vibrational motion may travel along the
longit~ in~l axis of the joined components with ~"ir,i~"~l losses and ",i"i.
conversion of longit~l~in~l energy into transverse vibrations.
Once the ~ sion rod 86 is tightened onto the mounting
device, the adapter 120 of the surgical system 10 is axially slipped over the
surgical ills~ mcllt 150 and ~rlle~l to the distal end of the handpiece
assembly 50. The adapter 120 may be threaded or snapped onto the distal
end of the housing 52.
CA 022~2798 l998-l0-27
W O ~8/37819 PCT~US98/03580
- 25 -
The adapter 120 includes an axial bore or lumen 122
configured to snugly fit over the hub 172 of the surgical instrument 150. The
lumen 122 has an inner surface having a selected geometric configuration,
such as, for example, substantially cylindrically or elliptically shaped.
Preferably, the lumen 122 has subst~n~i~lly the same shape as the hub 172 of
the outer sheath 170, but has a slightly larger diameter than the hub 172 to
allow the lumen 122 of the adapter 120 to pass over the hub 172. The hub
172 allows precise engagement with the inner diameter of the lumen of the
adapter 120 in order to ensure ~lignm~nt of the tr~ncmicsion rod 86 the
handpiece assembly 50.
The adapter 122 may be fabricated from Ultem~ or liquid
crystal polymer (LCP). The adapter 132 may also be made from a variety of
materials including other plastics, such as a polyetherimide, nylon or
polycarbonate, or any other suitable material.
To detach the surgical instrument 150 from the mounting
device 84 of the handpiece assembly 50, the tool may be slipped over the
tr~n.crni~sion rod 86 and rotated in the opposite direction, i.e., in a direction
to unthread the L~ iccion rod 86 from the mounting device 84. When the
tool is rotated, the hub 172 allows torque to be applied to the tr~ncmi.ccion
rod 86 through the coupling member 195, such as, for example, a pin, to
allow a relatively high disen~gin~ torque to be applied to rotate the
tr~ncmicsion rod 86 in the unthreading direction. As a result, the
tr~n.cmic.sion rod 86 loosens from the mounting device 84. Once the
tr~ncmicsion rod 86 is removed from the mounting device 84, the entire
surgical in~Llulllellt 150 may be thrown away.
Since the hub of the surgical in~llulnent 150 is constructed of a
material which distorts at temperatures normally used for heat sterilization in
hospitals, any ~U~ t to heat sterilize the surgical insll~lllelll 150 for reuse
results in a deformed hub to prevent the surgical illsLIulllelll 150 from being
used again. As shown in FIG. 11, when the hub 172 is sterilized with steam
.. .
CA 022~2798 1998-10-27
W O 98/37819 PCT/US98/03580
- 26 -
or otherwise exposed to heat and/or high humidity, the outside diameter of
the hub 172 deforms or becomes irregular upon resterilization in, for
example, a steam sterilizer or autoclave. As a result, the lumen 122 of the
adapter 120 cannot pass or slide over the hub 172 of the surgical instrument
S 150. Thus, the adapter 122 cannot be ~ r~le~l to the handpiece assembly
thereby preventing a user from reusing the surgical instrument 120.
Referring now to FIG. 13 and 14, another embodiment of a
single use surgical instrument 550 is illustrated. The surgical instrument 550
preferably includes a ~ ieeion component 552, a sheath 554, and one or
~ 10 more support members 560 (one being shown), such as, for example, an O-
ring. The tr~nemiesion component 552 may be substantially similar in
construction and function as the tr~nemiesion components as described above.
It is contemplated that the tr~nemiesion component 552 may be any suitable
tr~n~mi.e.eion component.
The sheath 554 of the surgical instrument 550 generally
includes a hub 556 and an elongated tubular member 558. The hub 556 and
the tubular member 558 may be substantially similar in construction and
function as the hub and tubular member as described above. It will be
recognized that the hub 556 and tubular member 558 may be constructed
from any suitable material and may be any suitable shape.
The support member 560 is disposed around the outer
periphery of the tr~nemie~ion component 552. The support member 560
positions the l~ --iesion component 552 with the hub 556 and reduces
vibration from being ~ e~l from the tr~n.emieeion component 552 to the
hub 556. The support member 560 is preferably positioned at a node of
lon~ din~l vibration of the ~ -..i.esion component 552 and is conetructed
of polymeric material, preferably silicone rubber. It is conl~."plated that the
support member may be constructed of any suitable material and may be
positioned at any suitable point along the l-~ ---iesion rod.
. . .
... .. . ..
CA 022~2798 1998-10-27
W O 98/37819 PCTAUS98/03580
The support member 560 preferably has one or more sections
of varying diameter. As illustrated in FIG. 14, the support member 560 has
four sections 562 of a first diameter and four sections 564 of a second
diameter. The second ~ m~ter of the four sections 564 is smaller than the
first diameter of the four sections 562. The four sections 564 create spaces
or channels 570 between the support member 560 and the hub 556 and the
support member 560 and the tran~mi~ion component 560. The channels 570
allow the surgical instrument to be initially sterilized by the m~nllf~t~lrer
with, for example, ethylene oxide (ETO). However, when resterilized, the
ch~nnPI~ 570 allow sterilizing agents, such as, for example, gases and fluids,
to pass by the support member 560 to enter a gap or space 580 between the
sheath and tr~n~mi~sion component 560. For example, the channels 570
allow sterilizing fluids to enter the gap 580 between the sheath and
transmission component 560 when the surgical instrument is submersed in
cleaning fluids. Once the sterilizing agents have entered into the gap 580,
the agents become trapped because of the close fit of the components. As a
result, ~i~nifi~nt loading will be added to the ultrasonic transmission
component and the ultrasonic tr~n~mi~ion rod will not be able to resonate,
thereby preventing reuse of the surgical instrument. ~t is contemplated that
the support member 560 may be any suitable shape to allow fluid to flow into
the space between the hub and the tr~n~mi~sion component. It will be
recognized that the tr~n~mi~sion component may have grooves or slots on its
outer surface and the sheath may have grooves or slots on its inner surface to
allow the passage of gases and fluid into the gap.
The surgical i~ ulllents of the present invention are preferably
configured and constructed to permit passage of ultrasonic energy through the
ultrasonic ~ .c~.~i.c~ion rod with minim~l lateral side-to-side movement of the
ultrasonic tr~n~mi~sion rod while, at the same time, pellllilLing unrestricted
longit~ in~l for~,vard/backward vibrational or movement of the ultrasonic
~ sion rod.
CA 022~2798 1998-10-27
W O 98/37819 PCT/US98/03580
The surgical instruments allow torque to be applied to the
tr~n~mi~sion component by a non-vibratory member. The surgical
instruments also allow use of the existing torque wrenches without requiring
large diameter wrench flats or surfaces. Since no large wrench flat features
are needed, the tr~n~mic.sion rod can be m~ ined from small diameter stock.
Accordingly, the ultrasonic tr~n~mi~sion rod can be made smaller reducing
the size of the entire ultrasonic package.
The surgical instruments allow medical personnel to quickly
and easily attach the surgical instruments to the handpiece. The surgical
instrument is desirably and beneficially applied to and removed from a
handpiece as a unit. The surgical instruments can be disposed of after a
smgle use.
Although the present invention has been described in detail by
way of illustration and example, it should be understood that a wide range of
changes and mo(lific~tions can be made to the preferred embodiments
described above without departing in any way from the scope and spirit of
the invention. Thus, the described embodiments are to be considered in all
aspects only as illustrative and not restrictive, and the scope of the inventionis, therefore, indic~te(l by the appended claims rather than the foregoing
description. All changes that come within the meaning and range of
equivalency of the claims are to be embraced within their scope.
