Patent Description:
Ultrasonic surgical instruments utilize ultrasonic energy for both precise cutting and controlled coagulation of tissue. The ultrasonic energy cuts and coagulates by vibrating a blade in contact with the tissue. Vibrating at frequencies of approximately <NUM> kilohertz (kHz), for example, the ultrasonic blade denatures protein in the tissue to form a sticky coagulum. Pressure exerted on the tissue with the blade surface collapses blood vessels and allows the coagulum to form a hemostatic seal. The precision of cutting and coagulation may be controlled by the surgeon's technique and adjusting the power level, blade edge, tissue traction, and blade pressure, for example.

Examples of ultrasonic surgical devices include the HARMONIC ACE® Ultrasonic Shears, the HARMONIC WAVE® Ultrasonic Shears, the HARMONIC FOCUS® Ultrasonic Shears, and the HARMONIC SYNERGY® Ultrasonic Blades, all by Ethicon Endo-Surgery, Inc. of Cincinnati, Ohio. Further examples of such devices and related concepts are disclosed in <CIT>, the disclosure of which is referenced herein; <CIT>, the disclosure of which is referenced herein; <CIT>, the disclosure of which is referenced herein; <CIT>, the disclosure of which is referenced herein; <CIT>, the disclosure of which is referenced herein; <CIT>, the disclosure of which is referenced herein; <CIT>, the disclosure of which is referenced herein; <CIT>, the disclosure of which is referenced herein; <CIT>, the disclosure of which is referenced herein; <CIT>, the disclosure of which is referenced herein; <CIT>, the disclosure of which is referenced herein; <CIT>, the disclosure of which is referenced herein; <CIT>, the disclosure of which is referenced herein; <CIT>, the disclosure of which is referenced herein; and <CIT>, the disclosure of which is referenced herein.

An ultrasonic surgical instrument generally includes an ultrasonic transducer and an ultrasonic blade configured to be driven by the ultrasonic transducer. Various ultrasonic surgical instruments enable the ultrasonic blade to be selectively attached and detached from the ultrasonic transducer, via a threaded coupling between the two components. It is desirable to apply an appropriate amount of torque to this threaded coupling when assembling the blade with the transducer. Applying too much torque can cause the threaded coupling to fracture and fail during use, and applying too little torque can cause the threaded coupling to loosen and inhibit effective transmission of ultrasonic energy to tissue during use. Either result is undesirable, and can render the surgical instrument ineffective or entirely inoperable. Ultrasonic blades and transducers of conventional ultrasonic surgical instruments may be assembled with a hand-held torque wrench tool that is provided separately from the surgical instrument. The torque wrench tool includes features that limit application of additional torque to the threaded coupling between the ultrasonic blade and transducer once a predetermined amount of torque has been reached. An example of such a torque wrench tool is disclosed in <CIT>, the disclosure of which is referenced herein.

While various types of ultrasonic surgical instruments and torque wrench mechanisms have been made and used, it is believed that no one prior to the inventor(s) has made or used the invention described herein.

For clarity of disclosure, the terms "proximal" and "distal" are defined herein relative to a surgeon, or other operator, grasping a surgical instrument having a distal surgical end effector. The term "proximal" refers to the position of an element arranged closer to the surgeon, and the term "distal" refers to the position of an element arranged closer to the surgical end effector of the surgical instrument and further away from the surgeon. Moreover, to the extent that spatial terms such as "upper," "lower," "vertical," "horizontal," or the like are used herein with reference to the drawings, it will be appreciated that such terms are used for exemplary description purposes only and are not intended to be limiting or absolute. In that regard, it will be understood that surgical instruments such as those disclosed herein may be used in a variety of orientations and positions not limited to those shown and described herein.

<FIG> show an exemplary ultrasonic surgical instrument (<NUM>) that includes a handle assembly (<NUM>), a shaft assembly (<NUM>) extending distally from handle assembly (<NUM>), and an end effector (<NUM>) arranged at a distal end of shaft assembly (<NUM>). Handle assembly (<NUM>) comprises a body (<NUM>) including a pistol grip (<NUM>) and energy control buttons (<NUM>) configured to be manipulated by a surgeon to control various aspects of tissue treatment energy delivered by surgical instrument (<NUM>). A trigger (<NUM>) is coupled to a lower portion of body (<NUM>) and is pivotable toward and away from pistol grip (<NUM>) to selectively actuate end effector (<NUM>). In other suitable variations of surgical instrument (<NUM>), handle assembly (<NUM>) may comprise a scissor grip configuration, for example. Body (<NUM>) houses an ultrasonic transducer (<NUM>), shown schematically in <FIG>, configured to deliver ultrasonic energy to end effector (<NUM>), as described in greater detail below. Body (<NUM>) may also be referred to herein as a housing (<NUM>) and may include one component or an assembly of components. The terms "body" and "housing" are thus not intended to unnecessarily limit the invention described herein to any number of discrete components.

As shown best in <FIG>, end effector (<NUM>) includes an ultrasonic blade (<NUM>) and a clamp arm (<NUM>) configured to selectively pivot toward and away from ultrasonic blade (<NUM>) for clamping tissue therebetween. Clamp arm (<NUM>) includes a clamp pad (<NUM>) arranged on a clamping side thereof and is moveable from an open position shown in <FIG> to a closed position shown in <FIG>. With respect to <FIG>, ultrasonic blade (<NUM>) is acoustically coupled with ultrasonic transducer (<NUM>), which is configured to drive (i.e., vibrate) ultrasonic blade (<NUM>) at ultrasonic frequencies for cutting and/or sealing tissue positioned in contact with ultrasonic blade (<NUM>). Clamp arm (<NUM>) is operatively coupled with trigger (<NUM>) such that clamp arm (<NUM>) is configured to pivot toward ultrasonic blade (<NUM>), to the closed position, in response to pivoting of trigger (<NUM>) toward pistol grip (<NUM>). Further, clamp arm (<NUM>) is configured to pivot away from ultrasonic blade (<NUM>), to the open position in response to pivoting of trigger (<NUM>) away from pistol grip (<NUM>). Various suitable ways in which clamp arm (<NUM>) may be coupled with trigger (<NUM>) will be apparent to those of ordinary skill in the art in view of the teachings provided herein. In some versions, one or more resilient members may be incorporated to bias clamp arm (<NUM>) and/or trigger (<NUM>) toward the open position.

Shaft assembly (<NUM>) of the present example extends along a longitudinal axis and includes an outer tube (<NUM>), an inner tube (<NUM>) received within outer tube (<NUM>), and an ultrasonic waveguide (<NUM>) supported within and extending longitudinally through inner tube (<NUM>). Ultrasonic blade (<NUM>) is formed integrally with and extends distally from waveguide (<NUM>). A proximal end of clamp arm (<NUM>) is pivotally coupled to distal ends of outer and inner tubes (<NUM>, <NUM>), enabling clamp arm (<NUM>) to pivot relative to shaft assembly (<NUM>) about a pivot axis defined by a pivot pin (<NUM>) (see <FIG>) extending transversely through the distal end of inner tube (<NUM>).

In the present example, inner tube (<NUM>) is longitudinally fixed relative to handle assembly (<NUM>), and outer tube (<NUM>) is configured to translate relative to inner tube (<NUM>) and handle assembly (<NUM>), along the longitudinal axis of shaft assembly (<NUM>). As outer tube (<NUM>) translates distally, clamp arm (<NUM>) pivots about its pivot axis toward its open position. As outer tube (<NUM>) translates proximally, clamp arm (<NUM>) pivots about its pivot axis in an opposite direction toward its closed position. Though not shown, a proximal end of outer tube (<NUM>) is operatively coupled with trigger (<NUM>) such that actuation of trigger (<NUM>) causes translation of outer tube (<NUM>) relative to inner tube (<NUM>), thereby opening or closing clamp arm (<NUM>) as discussed above. In other suitable configurations not shown herein, outer tube (<NUM>) may be longitudinally fixed and inner tube (<NUM>) may be configured to translate for moving clamp arm (<NUM>) between the open and closed positions. Various other suitable mechanisms for actuating clamp arm (<NUM>) between the open and closed positions will be apparent to those of ordinary skill in the art.

Shaft assembly (<NUM>) and end effector (<NUM>) are configured to rotate together relative to body (<NUM>) about the longitudinal axis defined by shaft assembly (<NUM>). As shown in <FIG>, shaft assembly (<NUM>) further includes a rotation knob (<NUM>) arranged at a proximal end thereof. Rotation knob (<NUM>) is rotatably coupled to body (<NUM>) of handle assembly (<NUM>), and is rotationally fixed to outer tube (<NUM>), inner tube (<NUM>), and waveguide (<NUM>) by a coupling pin (not shown) extending transversely therethrough. Coupling pin (not shown) is arranged at a longitudinal location corresponding to an acoustic node of waveguide (<NUM>). In other examples, rotation knob (<NUM>) may be rotationally fixed to the remaining components of shaft assembly (<NUM>) in various other manners. Rotation knob (<NUM>) is configured to be gripped by a user to selectively manipulate the rotational orientation of shaft assembly (<NUM>) and end effector (<NUM>) relative to handle assembly (<NUM>). Various examples of acoustic and mechanical connections between shaft assembly (<NUM>) and handle assembly (<NUM>) are described in greater detail in <CIT> and <CIT>, the disclosures of which are each referenced herein.

<FIG> show additional details of ultrasonic transducer (<NUM>) and waveguide (<NUM>). In particular, ultrasonic transducer (<NUM>) and waveguide (<NUM>) are configured to threadedly couple together. Accordingly, waveguide (<NUM>) is configured to acoustically couple ultrasonic transducer (<NUM>) with ultrasonic blade (<NUM>), and thereby communicate ultrasonic mechanical vibrations from ultrasonic transducer (<NUM>) to blade (<NUM>). In this manner, ultrasonic transducer (<NUM>), waveguide (<NUM>), and ultrasonic blade (<NUM>) together define an acoustic assembly of ultrasonic surgical instrument (<NUM>). Ultrasonic transducer (<NUM>) is rotatably supported within body (<NUM>) of handle assembly (<NUM>), and is configured to rotate with shaft assembly (<NUM>), including waveguide (<NUM>), and end effector (<NUM>) about the longitudinal axis of shaft assembly (<NUM>).

Ultrasonic transducer (<NUM>) is electrically coupled with a generator (not shown), which may be provided externally of ultrasonic surgical instrument (<NUM>) or integrated within surgical instrument (<NUM>). During use, generator (not shown) powers ultrasonic transducer (<NUM>) to produce ultrasonic mechanical vibrations, which are communicated distally through waveguide (<NUM>) to ultrasonic blade (<NUM>). Ultrasonic blade (<NUM>) is caused to oscillate longitudinally in the range of approximately <NUM> to <NUM> microns peak-to-peak, for example, and in some instances in the range of approximately <NUM> to <NUM> microns, at a predetermined vibratory frequency fo of approximately <NUM>, for example. Vibrating ultrasonic blade (<NUM>) may be positioned in direct contact with tissue, with or without assistive clamping force provided by clamp arm (<NUM>), to impart ultrasonic vibrational energy to the tissue and thereby cut and/or seal the tissue. For example, blade (<NUM>) may cut through tissue clamped between clamp arm (<NUM>) and a clamping side of blade (<NUM>), or blade (<NUM>) may cut through tissue positioned in contact with an oppositely disposed non-clamping side of blade (<NUM>) having an edge, for example during a "back-cutting" movement. In some versions, waveguide (<NUM>) may be configured to amplify the ultrasonic vibrations delivered to blade (<NUM>). Waveguide (<NUM>) may include various features operable to control the gain of the vibrations, and/or features suitable to tune waveguide (<NUM>) to a selected resonant frequency.

In the present example, ultrasonic transducer (<NUM>) includes a first resonator (or "end-bell") (<NUM>), a conically shaped second resonator (or "fore-bell") (<NUM>), and a transduction portion arranged between end-bell (<NUM>) and fore-bell (<NUM>) that includes a plurality of piezoelectric elements (<NUM>). A compression bolt (not shown) extends distally, coaxially through end-bell (<NUM>) and piezoelectric elements (<NUM>), and is threadedly received within a proximal end of fore-bell (<NUM>). A velocity transformer (or "horn") (<NUM>) extends distally from fore-bell (<NUM>) and includes an internally threaded bore (<NUM>) configured to receive and threadedly couple with an externally threaded proximal tip (<NUM>) of waveguide (<NUM>) as shown in <FIG>.

While the teachings herein are disclosed in connection with ultrasonic surgical instruments, it will be appreciated that they may also be employed in connection with surgical instruments configured to provide a combination of ultrasonic and radio frequency (RF) energies. Examples of such instruments and related methods and concepts are disclosed in <CIT>, the disclosure of which is referenced herein; <CIT>, the disclosure of which is referenced herein; and <CIT>, the disclosure of which is referenced herein.

Given that various portions of ultrasonic surgical instrument (<NUM>) removably connect together, it may be desirable in various examples to reuse some portions of ultrasonic surgical instrument (<NUM>) while replacing others upon reconnection for further use by the surgeon. For example, handle assembly (<NUM>) in the present example is reusable whereas shaft assembly (<NUM>) may be disconnected and replaced with an unused, replacement shaft assembly (<NUM>). Despite the reusability of handle assembly (<NUM>), one or more components of handle assembly (<NUM>) may be replaced after a predetermined number of use cycles of use for each respective patient treatment. For example, ultrasonic transducer (<NUM>) may operate efficiently and effectively up to five use cycles, but performance may deteriorate beyond the five use cycles such that replacement of handle assembly (<NUM>) is desirable.

While such reuse of handle assembly (<NUM>) followed by replacement of handle assembly (<NUM>) may be desirable, inhibiting reuse beyond the predetermined number of use cycles may be complicated, difficult, or tedious given that inspection of handle assembly (<NUM>) may not readily communicate the predetermined complete usage of handle assembly (<NUM>). An integrated usage indicator (<NUM>) with a used state indicator as described below may thus be desirable in some instance for indicating usage to a clinician, such as the surgeon, without the need for manually tracking such usage separate from handle assembly (<NUM>). Once used state indicator indicates such use in a used state to the clinician, a replacement handle assembly (<NUM>) may be used for a following patient treatment. While various examples are given below regarding a particular number of uses and/or reuses, it will be appreciated that any number of uses and/or reuses may be possible in other examples. The invention is thus not intended to be unnecessarily limited to a particular number of uses and/or reuses.

The following description provides various examples of integrated usage indicators (<NUM>). Such integrated usage indicators (<NUM>) described below may be used with any ultrasonic surgical instrument described above and below and in any of the various procedures described in the various patent references cited herein. To this end, like numbers below indicated like features described above. Other suitable ways in which various ultrasonic surgical instruments may be used will be apparent to those of ordinary skill in the art in view of the teachings herein.

<FIG> illustrate a ultrasonic surgical instrument (<NUM>) having a handle assembly (<NUM>) configured to be operated up to a predetermined number of use cycles, shaft assembly (<NUM>) configured for a single use cycle of treatment, and a wheel ratchet usage indicator (<NUM>). With respect to <FIG>, wheel ratchet usage indicator (<NUM>) is integrated into a housing (<NUM>) of handle assembly (<NUM>) for recording and indicating each respective use cycle of handle assembly (<NUM>) in a use remaining state to a used state. Wheel ratchet usage indicator (<NUM>) has a housing portion (<NUM>) that cooperates with shaft assembly (<NUM>) upon connection of shaft assembly (<NUM>) to handle assembly (<NUM>) to thereby direct wheel ratchet usage indicator (<NUM>) toward the used state with each replacement shaft assembly (<NUM>). Once shaft assembly (<NUM>) has been replaced the predetermined number of use cycles, wheel ratchet usage indicator (<NUM>) indicates the used state of handle assembly (<NUM>) to the clinician. Such indication of wheel ratchet usage indicator (<NUM>) is visual as well as a lockout, which inhibits operation of handle assembly (<NUM>).

Housing portion (<NUM>) of wheel ratchet usage indicator (<NUM>) includes an actuator (<NUM>), an indicia window (<NUM>) through housing (<NUM>), a rotatable wheel mount (<NUM>), a ratchet mechanism (<NUM>), and a wheel ratchet (<NUM>). Actuator (<NUM>) of the present example is a distal end of ultrasonic transducer (<NUM>). Wheel ratchet (<NUM>) is rotatably mounted to wheel mount (<NUM>) within housing (<NUM>), whereas ratchet mechanism (<NUM>) is translatably mounted within housing (<NUM>) and biased in the proximal direction toward actuator ultrasonic transducer (<NUM>). In the present example, threadably connecting waveguide (<NUM>) to ultrasonic transducer (<NUM>) distally pulls ultrasonic transducer (<NUM>) from a proximal position to a distal position. Thereby, actuator (<NUM>) is configured to distally urge ratchet mechanism (<NUM>) into engagement with wheel ratchet (<NUM>) for rotating wheel ratchet (<NUM>) while wheel ratchet (<NUM>) is visible to clinician through indicia window (<NUM>) as discussed below in greater detail.

In the present example, ratchet mechanism (<NUM>) is a pawl tab (<NUM>) configured to be distally translated by actuator (<NUM>) as ultrasonic transducer (<NUM>) slides from the proximal position to the distal position. Pawl tab (<NUM>) is more particularly rigid in the longitudinal direction so as to engage and rotate wheel ratchet (<NUM>), but resiliently deflectable in the lateral direction. Wheel ratchet (<NUM>) has an upper ratchet gear (<NUM>) with a plurality of radially projecting slip ratchet teeth (<NUM>) about rotatable wheel mount (<NUM>). Upper ratchet gear (<NUM>) is attached to and extending upward from a lower wheel body (<NUM>). Pawl tab (<NUM>) is thus configured to engage slip ratchet teeth (<NUM>) while moving the distal direction and urge wheel ratchet (<NUM>) in the clockwise direction, but inhibit movement in the counterclockwise direction. In addition, wheel ratchet usage indicator (<NUM>) further includes an arrester (<NUM>). Arrester (<NUM>) has a plurality of detent tabs (<NUM>) configured to engage a detent catch (not shown) below lower wheel body (<NUM>) and fixed within housing (<NUM>). Cooperation between detent tabs (<NUM>) positioned on lower wheel body (<NUM>) and detent catch (not shown) further inhibits inadvertent clockwise or counterclockwise rotation of wheel ratchet (<NUM>). In the present example, "clockwise" and "counterclockwise" refer to rotation of wheel ratchet (<NUM>) as viewed from a top view of wheel ratchet (<NUM>).

In the present example, with respect to <FIG>, shaft assembly (<NUM>) mechanically and acoustically couples to handle assembly (<NUM>) by rotation similar to shaft and handle assemblies (<NUM>, <NUM>) (see FIG. Threadably connecting waveguide (<NUM>) with ultrasonic transducer (<NUM>) distally pulls ultrasonic transducer (<NUM>) with actuator (<NUM>) into engagement with pawl tab (<NUM>) of ratchet mechanism (<NUM>). Pawl tab (<NUM>) in turn urges slip ratchet teeth (<NUM>) clockwise direction with sufficient force to overcome arrester (<NUM>). Disconnecting waveguide (<NUM>) from ultrasonic transducer (<NUM>) causes ultrasonic transducer (<NUM>) with actuator (<NUM>) to proximally return to the proximal position such that pawl tab (<NUM>) slips proximally along slip ratchet teeth (<NUM>). Arrester (<NUM>) is configured to secure wheel ratchet (<NUM>) such that pawl tab (<NUM>) slips without also rotating wheel ratchet (<NUM>) in the counterclockwise direction. Slip ratchet teeth (<NUM>) each include engagement and ramp portions (648a, 648b) to further aid to respective urging and slipping of wheel ratchet (<NUM>) similar to those discussed above in other examples herein.

As briefly discussed above, indicia window (<NUM>) (see <FIG>) provides clinician with visual identification of the angular position of wheel ratchet (<NUM>). The relative angular position is recorded by a series of counter indices (<NUM>), which are angularly positioned about wheel ratchet (<NUM>) and increasing in the counterclockwise direction. The present example of counter indices (<NUM>) includes counterclockwise increasing numbers "<NUM>," "<NUM>," "<NUM>," "<NUM>," and "<NUM>" and are respectively configured to correspond to each replacement shaft assembly (<NUM>) used with handle assembly (<NUM>) in relation to the rotational position of wheel ratchet (<NUM>). For example, as shown in <FIG> and <FIG>, a first counter indicia (<NUM>) "<NUM>" transversely aligns through indicia window (<NUM>) to indicate to the clinician that handle assembly (<NUM>) is in its first use.

Successive connections of replacement shaft assemblies (<NUM>) continue to rotate wheel ratchet (<NUM>) until a fifth counter indicia (<NUM>) "<NUM>" transversely aligns through indicia window (<NUM>) to visually indicate the used state of handle assembly (<NUM>). In addition, wheel ratchet usage indicator (<NUM>) is configured to mechanically inhibit further connection of replacement shaft assemblies (<NUM>) greater than the predetermined number of use cycles. More particularly, arrester (<NUM>) engages wheel ratchet (<NUM>) in the used state to inhibit further clockwise rotation thereof. Wheel ratchet usage indicator (<NUM>) is thereby configured to inhibit inadvertently using handle assembly (<NUM>) beyond the predetermined number of use cycles.

In use, with respect to <FIG>, the clinician connects first replacement shaft assembly (<NUM>) to handle assembly (<NUM>) such that actuator (<NUM>) urges wheel ratchet (<NUM>) in alignment with the first indicia (<NUM>) for indicating the first use to clinician. Following treatment of the patient, shaft assembly (<NUM>) is disconnected from handle assembly (<NUM>) by slipping pawl tab (<NUM>) by ramp portions (648b) of slip ratchet teeth (<NUM>). Handle assembly (<NUM>) is then prepped, such as by heating and/or sterilizing, for another surgical procedure and another replacement shaft assembly (<NUM>) is connected to handle assembly (<NUM>). Actuator (<NUM>) of the second replacement shaft assembly (<NUM>) urges wheel ratchet (<NUM>) in alignment with the second indicia for indicating the second use to the clinician. Such reuse continues in the remaining use state until arrester (<NUM>) engages wheel ratchet (<NUM>) in the used state.

Similarly, those of ordinary skill in the art will recognize that various teachings herein may be readily combined with various teachings of any of the following: <CIT>, the disclosure of which is referenced herein; <CIT>, the disclosure of which is referenced herein; <CIT>, the disclosure of which is referenced herein; <CIT>, the disclosure of which is referenced herein; <CIT>, the disclosure of which is referenced herein; <CIT>, the disclosure of which is referenced herein; <CIT>, the disclosure of which is referenced herein; <CIT>, the disclosure of which is referenced herein; <CIT>, the disclosure of which is referenced herein; <CIT>, the disclosure of which is referenced herein; <CIT>, the disclosure of which is referenced herein; <CIT>, the disclosure of which is referenced herein; <CIT>, the disclosure of which is referenced herein; <CIT>, the disclosure of which is referenced herein; <CIT>, the disclosure of which is referenced herein; <CIT>, the disclosure of which is referenced herein; <CIT>; <CIT>, the disclosure of which is referenced herein; and/or <CIT>, the disclosure of which is referenced herein.

Claim 1:
An ultrasonic surgical instrument (<NUM>), comprising:
(a) a housing (<NUM>) configured to removably connect to a shaft assembly (<NUM>);
(b) an ultrasonic transducer (<NUM>) supported by the housing and having a transducer connector configured to connect to a waveguide (<NUM>) for acoustically connecting the ultrasonic transducer to the waveguide, wherein the ultrasonic transducer is configured to be operated up to a predetermined number of use cycles; and
(c) an integrated usage indicator (<NUM>) operatively connected to the housing and including a used state indicator (<NUM>), wherein the used state indicator is configured to indicate to a clinician in a used state when the ultrasonic transducer has been operated at least the predetermined number of use cycles for limiting usage of the ultrasonic transducer to the predetermined number of use cycles; characterised
in that the integrated usage indicator further includes a ratchet (<NUM>) having the used state indicator thereon, wherein the ratchet is configured to be directed in a first direction toward the used state upon acoustic connection of the waveguide to the ultrasonic transducer, wherein the ratchet is ratcheted to inhibit the ratchet from moving in a second direction opposite from the first direction, and wherein the ultrasonic transducer has an actuator (<NUM>) configured to urge the ratchet in the first direction upon acoustically connecting the wave guide to the ultrasonic transducer.