CA2252798A1 - Preventing reuse of surgical devices - Google Patents

Abstract

A single use ultrasonic surgical device (150) in accordance with the present invention includes a transmission component (86) adapted to receive ultrasonic vibration from a transducer assembly (82) and to transmit the ultrasonic vibration from a first end to a second end. A hub (172) is coupled to the transmission component and includes a temperature sensitive material that distorts when exposed to heat. An ultrasonic surgical device (150) in accordance with the present invention includes a transducer assembly (82) adapted to vibrate at an ultrasonic frequency in response to electrical energy. A transmission rod (86) is adapted to receive ultrasonic vibration from the transducer assembly and to transmit the ultrasonic vibration from a first end to a second end of the transmission rod. A sheath (170) surrounds at least a portion of the transmission rod and includes a temperature sensitive material that distorts when exposed to heat. An end effector (88) is adapted to receive the ultrasonic vibration from the transmission rod (86) and to transmit the ultrasonic vibration from a first end to a second end 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 transmission rod. In an alternative arrangement, the sterilization of the instrument (550) inhibits the ultrasonic transmission capabilities of the instrument to prevent reuse.

Description

CA 022~2798 1998-10-27 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 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 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 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 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 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 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 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 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 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 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 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 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 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 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 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 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 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 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 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 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 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.

Claims (26)

WHAT IS CLAIMED IS:

1. An ultrasonic surgical device comprising:
a transducer assembly adapted to vibrate at an ultrasonic frequency in response to electrical energy;
a mounting device having a first end and a second end, the mounting device adapted to receive ultrasonic vibration from the transducer assembly and to transmit the ultrasonic vibration from the first end to the second end of the mounting device, the first end of the mounting device coupled to the transducer assembly;
a transmission rod having a first end and a second end, the transmission rod adapted to receive ultrasonic vibration from the mounting device and to transmit the ultrasonic vibration from the first end to the second end of the transmission rod;
a sheath surrounding at least a portion of the transmission rod, the sheath including a temperature sensitive material that distorts when exposed to heat to prevent reuse of the transmission rod; and an end effector having a first end and a second end, the end effector adapted to receive the ultrasonic vibration from the transmission rod and transmit the ultrasonic vibration from the first end to the second end of the end effector, the second end of the end effector being disposed near an antinode and the first end of the end effector coupled to the second end of the transmission rod.

2. The device of claim 2 wherein the material includes copolyester-polycarbonate alloy.

3. The device of claim 2 wherein the sheath includes a hub and a elongated member, the elongated member extending distally from the hub and concentric with the transmission rod.

4. An ultrasonic surgical device comprising:
a transducer assembly adapted to vibrate at an ultrasonic frequency in response to electrical energy;
a transmission rod having a first end and a second end, the transmission rod adapted to receive ultrasonic vibration from the transducer assembly and to transmit the ultrasonic vibration from the first end to the second end of the transmission rod; and a sheath surrounding at least a portion of the transmission rod, the sheath including a temperature sensitive material that distorts when exposed to heat; and an end effector having a first end and a second end, the end effector adapted to receive the ultrasonic vibration from the transmission rod and to transmit the ultrasonic vibration from the first end to the second end of the end effector, the second end of the end effector disposed near an antinode and the first end of the end effector coupled to the second end of the transmission rod.

5. The device of claim 4 wherein the sheath includes an elongated member extending from a hub, wherein the elongated member surrounds, at least partially, the transmission rod.

6. The device of claim 5 wherein the hub is constructed of a polymer material.

7. The device of claim 4 further comprising a plurality of axially spaced compliant members interposed between the sheath and the transmission rod to maintain the sheath at a predetermined distance from the transmission rod, the compliant members being disposed substantially near nodes.

8. The device of claim 5 wherein the hub is integrally attached to the transmission rod.

9. The device of claim 4 further including an adapter having a longitudinal lumen extending therethrough, the lumen being configured to slip over the sheath; and wherein the lumen will not slip over the sheath after the sheath is exposed to heat.

10. The device of claim 4 further comprising at least one compliant member coupled to the sheath.

11. The device of claim 4 wherein the transmission rod is substantially semi-flexible.

12. The device of claim 4 wherein the ultrasonic device comprises an endoscopic instrument.

13. The device of claim 4 further comprising a generator to energize the transducer assembly.

14. The device of clam 4 further comprising a handpiece assembly to carry the transducer assembly.

15. The device of claim 4 wherein the ultrasonic device comprises an angioplasty catheter assembly.

16. The device of claim 4 wherein the transmission rod comprises a wire.

17. A single use ultrasonic surgical device comprising:
a transducer assembly adapted to vibrate at an ultrasonic frequency in response to electrical energy;
a transmission rod having a first end and a second end, the transmission rod adapted to receive ultrasonic vibration from the transducer assembly and to transmit the ultrasonic vibration from the first end to the second end of the transmission rod; and a temperature sensitive material surrounding at least a portion of the transmission rod, the material adapted to distort when exposed to heat;
and an end effector having a first end and a second end, the end effector adapted to receive the ultrasonic vibration from the transmission rod and to transmit the ultrasonic vibration from the first end to the second end of the end effector, the second end of the end effector disposed near an antinode and the first end of the end effector coupled to the second end of the transmission rod.

18. A single use ultrasonic surgical device for use with a handpiece assembly comprising:
a transmission component having a first end and a second end, the transmission component adapted to receive ultrasonic vibration from a transducer assembly and to transmit the ultrasonic vibration from the first end to the second end; and a hub coupled to transmission component, the hub having a shape that changes with temperature to prevent attachment to the handpiece assembly.

19. An ultrasonic surgical instrument comprising:
a working member having a shaft;

the shaft having a first end and a second end, the shaft adapted to receive ultrasonic vibration and to transmit the ultrasonic vibration from the first end to the second end of the shaft; and a temperature sensitive material surrounding at least a portion of the shaft, the heat sensitive material adapted to distort upon exposure to a change in temperature to prevent reuse of the working member.

20. The ultrasonic device of claim 19 further including an end effector having a first end and a second end, the end effector being adapted to receive the ultrasonic vibration from the shaft and transmit the ultrasonic vibration from the first end to the second end of the end effector, the first end of the end effector coupled to the second end of the working member.

21. A surgical device comprising:
a transmission component having a first end and a second end, the transmission component adapted to receive ultrasonic vibration and to transmit the ultrasonic vibration from the first end to the second end of the transmission component; and a sheath surrounding at least a portion of the transmission component; and a support member positioned between the transmission component and the sheath forming a passageway to allow a sterilizing agent to pass thereby to prevent reuse of the surgical instrument upon resterilization.

22. The device of claim 21 wherein the support member has a first cross sectional diameter and a second cross sectional diameter, the second diameter being smaller than the first cross sectional diameter to form a channel to allow the medium to pass.

23. The device of claim 21 wherein the transmission component includes a slot on its outer surface to allow the sterilizing agent topass.

24. The device of claim 21 wherein the sheath includes a slot on its inner surface to allow the sterilizing agent to pass.

25. The device of claim 21 wherein the sterilizing agent comprises a fluid.

26. The device of claim 21 wherein the sterilizing agent comprises a gas.