Patent Description:
The invention relates generally to surgical device for cutting soft tissue and more particularly, a soft tissue cutting instrument with a retractable blade or hook.

During surgery, soft tissue is incised by inserting a cutting device with a surgical blade or hook blade into a surgical site within the body. Some current cutting devices have an exposed surgical blade or hook blade. If the blade on the cutting device is exposed, there is a potential of injury to both the user and the patient. In one example, the user is at risk of injury from the exposed blade while handling the cutting device. In another example, the patient is at risk of injury when the exposed blade enters or exits the body. When an exposed blade enters or exits the body, it may inadvertently cut soft tissue.

In addition, current cutting devices are not ergonomically designed for the user, which may also contribute to mishandling and risk injury of the user and the patient.

Therefore, there is a need for an easy-to-use surgical instrument for cutting soft tissue that has a protectable blade or hook blade.

In addition, in the field of handheld manually actuated medical instruments, it is often desired to have the device actuated by the thumb/finger(s) of the user resulting in two or more discrete positions of one or more components relative to each other. Furthermore, it is often desired to have these positions maintained even after the finger/thumb of the user is removed from the button/switch/lever/slide/etc. of the instrument. Additionally, it is often desired to have the instrument maintain these positions of components even if the instrument is acted upon by outside forces other than those applied by the user of the instrument for the purposes of actuating or de-actuating the instrument, such as the reaction forces the instrument may encounter when performing work on the subject (the patient, another medical device, etc). The inventors of the current disclosure have recognized that without a locking mechanism, such forces could potentially "back drive" the instrument into an undesired condition of actuation/de-actuation.

While a number of mechanisms exist to "lock" the user-instrument interface to prevent back-driving of a mechanism within such an instrument, all have drawbacks. For example, A friction "detent" is a common means to "lock" a mechanism into a particular location/ configuration. However, since friction performs the holding of the element(s) of the mechanism in place, this holding ability can be overpowered by outside forces greater in magnitude than the friction forces in the detent mechanism. A "lock button" that holds, locks, or otherwise "pins into place" a user interface actuator such as a slide, a trigger, or a lever provides a positive locking of the interface that is resistant to back-driving when outside forces are applied. However, actuating the "lock button" itself requires the user to perform a second action in addition to the main action of using the interface itself. Additionally, the user must be mindful to remember to de-actuate the "lock button" before attempting to de-actuate the instrument or else de-actuation could be impossible (at least without breaking or deforming the mechanism). A "gated shifter" type of actuator, where during the course of actuation, there are one or more laterally offset "parking locations" into which the actuator engages, preventing the actuator from being actuated any further and preventing the mechanism(s) from being back-driven by outside forces, can be used. However, the lateral motion needed to place the actuator into one of the "parking locations" isn't left-right handed universal. While a right-handed user may be able to quickly flick an actuator one direction laterally, a left-handed user may find it more difficult to perform the same actuation in the same direction (same direction with respect to the instrument). Further, motions along multiple separate axes (e.g., longitudinal and lateral) may prove to be difficult and/or cause issues during a medical procedure, where movement along a single axis (linear movement) would be easier for a user. The document <CIT> discloses a system and method for cutting tissue with a retractable surgical cutting device according to the preamble of claim <NUM>. The documents <CIT>, <CIT>, <CIT> disclose further related systems. The document <CIT> discloses an electrosurgical mechanism including a rotary knob.

Therefore, there is a need for a mechanism that allows for actuation of a medical device and locking of the same per movement of an actuator along a single axis (linear movement).

Description of the Related Art Section Disclaimer: To the extent that specific patents/publications/products are discussed above in this Description of the Related Art Section or elsewhere in this disclosure, these discussions should not be taken as an admission that the discussed patents/publications/products are prior art for patent law purposes. For example, some or all of the discussed patents/publications/products may not be sufficiently early in time, may not reflect subject matter developed early enough in time and/or may not be sufficiently enabling so as to amount to prior art for patent law purposes. To the extent that specific patents/publications/products are discussed above in this Description of the Related Art Section and/or throughout the application, the descriptions/disclosures of which are all hereby incorporated by reference into this document in their respective entirety(ies).

The invention is directed to a retractable surgical cutting device as defined in claim <NUM>. No surgical methods form part of the invention. In one embodiment the The device includes a handle having a first channel extending therethrough. A switch located on the handle, the switch being movable between a retracted position and an extended position. An actuator extends through the first channel and connects to the switch within the handle. The actuator also comprises a blade at its distal end. The blade can include, but is not limited to, any shaped blade including a straight blade, angled blade (angled from itself and/or the shaft), curved blade (curved from itself and/or the shaft) or a hook blade etc. An outer sheath is connected to the handle and surrounds the actuator and at least a portion of the blade. A drive mechanism is connected to the switch within the handle such that when the switch moves from the retracted position to the extended position, the actuator moves from a retracted position to an extended position. When the actuator is in the retracted position, the blade can be (although does not have to be) entirely within the outer sheath (as in a preferred embodiment), and when the actuator is in the extended position, at least a portion of the blade is out of the outer sheath.

In another embodiment of the device, the device includes a handle having a first channel extending therethrough and a switch located thereon. The switch is movable between a retracted position and an extended position. An actuator extends through the first channel and connects to a proximal end of the first channel within the handle. The actuator has a blade at its distal end. An outer sheath surrounds the actuator and at least a portion of the blade. The outer sheath interfaces with the switch. A drive mechanism is connected to the switch within the handle such that when the switch moves from the retracted position to the extended position, the outer sheath moves from a retracted position to an extended position. When the outer sheath is in the retracted position, the blade is fully positioned within (although does not have to be) the outer sheath (as in a preferred embodiment) and when the outer sheath is in the extended position, at least a portion of the blade is positioned outside of the outer sheath.

In one embodiment, the present disclosure provides a method for cutting tissue. The method comprises the steps of: (i) providing a retractable surgical cutting device having a handle with a first channel extending therethrough, a switch located on the handle which is movable between a retracted position and an extended position, an actuator which extends to a proximal end of the first channel, a blade at a distal end of the actuator, an outer sheath interfacing the switch, the outer sheath surrounding the actuator and at least a portion of the blade; and a drive mechanism connected to the switch within the handle; (ii) moving the switch in a first direction along a longitudinal x-axis extending through the device; (iii) moving the outer sheath, via the drive mechanism, relative to the actuator; and (iv) exposing at least a portion of the blade. The method can further include the steps of advancing the outer sheath into a surgical site, and cutting tissue at a surgical site with the blade.

In a further embodiment of the device, the device includes a handle including a handle proximal end, a handle distal end, an outer surface, and an internal space, the handle extending along a central longitudinal axis; an actuator located and movable in a first direction to a first actuator position and in a second direction to a second actuator position on the outer surface of the handle; a sheath extending along the central longitudinal axis and including a sheath proximal end and a sheath distal end, wherein the sheath proximal end is positioned within the internal space of the handle, and wherein the sheath is configured to move in the first direction to a sheath first position, and is configured to move in a second direction to a sheath second position; a shaft at least partially positioned within the sheath and extending along the central longitudinal axis and including a shaft proximal end and a shaft distal end, wherein the shaft proximal end is connected to the interior surface of the handle and the shaft distal end includes a blade; and a drive and locking mechanism connected to the actuator and to the sheath within the internal space of the handle, wherein the drive and locking mechanism is configured to move the sheath in the first direction and lock the sheath in the sheath first position in response to movement of the actuator in one of the first direction or the second direction, and wherein the drive mechanism is configured to move the sheath in the second direction and lock the sheath in the sheath second position in response to movement of the actuator in the other one of the first direction or the second direction.

In an additional embodiment of the device, the device includes a handle including a handle proximal end, a handle distal end, an outer surface, and an internal space, the handle extending along a central longitudinal axis; an actuator located and movable in a first direction to a first actuator position and in a second direction to a second actuator position on the outer surface of the handle; a sheath extending along the central longitudinal axis and including a sheath proximal end and a sheath distal end, wherein the sheath proximal end is positioned within the internal space of the handle, and wherein the proximal end of the sheath is connected to the interior surface of the handle; a shaft at least partially positioned within the sheath and extending along the central longitudinal axis and including a shaft proximal end and a shaft distal end, wherein the shaft is configured to move in the first direction to a shaft first position, and is configured to move in a second direction to a shaft second position; and a drive and locking mechanism connected to the actuator and to the shaft within the internal space of the handle, wherein the drive and locking mechanism is configured to move the shaft in the first direction and lock the shaft in the shaft first position in response to movement of the actuator in one of the first direction or the second direction, and wherein the drive mechanism is configured to move the shaft in the second direction and lock the shaft in the shaft second position in response to movement of the actuator in the other one of the first direction or the second direction.

In accordance with an embodiment, the actuation and locking mechanism achieves a primary technical outcome of allowing the user to lock an actuated component of a handheld, manually-actuated surgical instrument at either end of a range of travel, to prevent "back-driving" of any components, locking them in place without need to perform any other additional actions or motions, or to interface with any other switches or buttons to "lock" the actuation into place. In one embodiment, the locking is not performed by friction, resulting in a resistance to back-driving any components of the device by overpowering any friction that may be used to temporarily hold the device in a particular state of actuation/ de-actuation. This positive, mechanical, locking function is entirely integral to the exact same motion that is used to bring about the actuation/ de-actuation of the instrument.

One or more aspects of the present invention are particularly pointed out and distinctly claimed as examples in the claims at the conclusion of the specification. The foregoing and other objects, features, and advantages of the invention are apparent from the following description taken in conjunction with the accompanying drawings in which:.

Aspects of the present invention and certain features, advantages, and details thereof, are explained more fully below with reference to the non-limiting examples illustrated in the accompanying drawings. Descriptions of well-known structures are omitted so as not to unnecessarily obscure the invention in detail. It should be understood, however, that the detailed description and the specific non-limiting examples, while indicating aspects of the invention, are given by way of illustration only, and are not by way of limitation. Various substitutions, modifications, additions, and/or arrangements, within the scope of the underlying inventive concepts will be apparent to those skilled in the art from this disclosure.

Referring now to <FIG>, there is shown a side view schematic representation of an illustrative embodiment of a retractable surgical cutting device <NUM>. The device <NUM> comprises a handle <NUM> connected to an outer sheath <NUM>, which extends to a distal blade <NUM>. The blade <NUM> is selectively extended and retracted upon actuation of an actuator (e.g., button, switch, lever, or knob) <NUM> on the handle <NUM>, as will be explained in detail later. As shown in <FIG>, the handle <NUM> can include thumb and finger grooves such that the shape of the handle <NUM> is ergonomic. The ergonomic design of the handle <NUM> provides increased control of the device <NUM> for its intended use. In other embodiments, the handle <NUM> may have fewer grooves or no grooves entirely. In some embodiments, the handle <NUM> is composed of plastic; however, the handle <NUM> may be composed of stainless steel or other traditional materials suitable for surgical devices.

Turning now to <FIG>, there is shown an exploded view schematic representation of the illustrative embodiment the retractable surgical cutting device <NUM> of <FIG>. In the depicted embodiment, the handle <NUM> of the device <NUM> is comprised of two pieces, a first piece <NUM> and a second piece <NUM>, having one or more channels therethrough. It is contemplated that in an alternative embodiment, the handle <NUM> may be composed of a single piece molded or otherwise formed around the inner components of the handle <NUM>. Continuing with <FIG>, the handle <NUM> comprises a first channel <NUM>, which is sized, dimensioned, and otherwise configured for an actuator <NUM>, which is connected to the blade <NUM>. The actuator <NUM> moves longitudinally within the outer sheath <NUM> in both directions along an x-axis, which extends approximately through the center of the handle <NUM>. The longitudinal movement of the actuator <NUM> is caused by a drive mechanism <NUM> within the handle <NUM>, as will be described in detail later. In other embodiments, the actuator <NUM> remains stationary while the drive mechanism <NUM> moves the outer shaft <NUM> relative to the actuator <NUM> and the blade <NUM>. In the one embodiment, the actuator <NUM> comprises the blade <NUM> machined on its distal end <NUM>. Thus, the embodiment of the actuator <NUM> and blade <NUM> can be a single-piece embodiment.

Referring now to <FIG>, there are shown top view schematic representations of illustrative embodiments of a blade. The blade <NUM> in <FIG> comprises an aperture <NUM> for connecting to the actuator <NUM> in a two-piece embodiment of the actuator <NUM> and blade <NUM>. <FIG> shows an embodiment wherein the blade <NUM> is a hook blade having at least one sharp edge <NUM> and one non-sharp edge <NUM>. <FIG> shows an embodiment wherein the blade <NUM> is a surgical blade with two sharp edges <NUM> (e.g., top and bottom). Any combination and number of sharp edges <NUM> and/or non-sharp edges <NUM> is contemplated for the blade <NUM>.

Referring now to <FIG>, there is shown a top and side view schematic representation of an illustrative embodiment of the actuator <NUM> of a two-piece actuator <NUM> and blade <NUM>. In comparison to a one-piece actuator <NUM> including the blade <NUM>, the actuator <NUM> of <FIG> is separate from and not otherwise machined onto the blade <NUM>. The actuator <NUM> in <FIG> comprises one or more notches for connecting to the blade <NUM> and the drive mechanism <NUM>. At the proximal end <NUM> of the actuator <NUM> there is a notch <NUM> for connecting the actuator <NUM> to the drive mechanism <NUM>. In another embodiment, the notch <NUM> at the proximal end <NUM> may be an aperture or other means for attaching the drive mechanism <NUM> to the actuator <NUM>. The actuator <NUM> can also comprise one or more notches <NUM>, <NUM> at its distal end <NUM>. The notches <NUM>, <NUM> at the distal end <NUM> of the actuator <NUM> are configured for attachment to the blade <NUM>.

Turning now to <FIG>, there are shown various views of schematic representations of an illustrative embodiment of the distal end <NUM> of the two-piece actuator <NUM> and blade <NUM>. As shown in <FIG>, the distal end <NUM> of the actuator <NUM> has a first notch <NUM> and a second notch <NUM>, while the blade <NUM> has an aperture <NUM> at its proximal end <NUM>. In the depicted embodiment, the first notch <NUM> and the second notch <NUM> have recesses which extend in directions opposing each other. To assemble the two-piece actuator <NUM> and blade <NUM>, the distal end <NUM> of the actuator <NUM> is inserted at an angle into the aperture <NUM> at the proximal end <NUM> of the blade <NUM>. The distal end <NUM> of the actuator <NUM> is so inserted until the second notch <NUM> is through the aperture <NUM>. Thereafter, the proximal end <NUM> of the actuator <NUM> (shown in <FIG>) is rotated away from the blade <NUM> and into the same plane as the blade <NUM>, locking the blade <NUM> into place, as shown in <FIG>. The second notch <NUM> on the distal end <NUM> of the actuator <NUM> engages the blade <NUM> on a distal side <NUM> of the aperture <NUM>, while the first notch <NUM> engages the blade <NUM> on a proximal side <NUM> of the aperture <NUM>, as shown in <FIG>.

Referring now to <FIG>, there is shown a top view schematic representation of an illustrative embodiment of a proximal end <NUM> and a distal end <NUM> of an outer sheath <NUM>. In the depicted embodiment, the outer sheath <NUM> is cannulated such that the outer sheath <NUM> has a first inner volume <NUM>. The outer sheath <NUM> is sized and dimensioned to fit around the actuator <NUM> and at a least a portion of the blade <NUM>. In other words, the actuator <NUM> and the blade <NUM> are inserted into the first inner volume <NUM> of the outer sheath <NUM> such that the outer sheath <NUM> surrounds the actuator <NUM> and at least a portion of the blade <NUM> (as shown in <FIG>). The outer sheath <NUM> is fixed to the handle <NUM> of the device <NUM> such that the longitudinal movement of the actuator <NUM> (via the drive mechanism <NUM>) extends and retracts the blade <NUM> from the outer sheath <NUM>. In alternative embodiments, the outer sheath <NUM> is fixed to the switch <NUM> and longitudinal movement of the switch along the x-axis moves the outer sheath <NUM> relative to a stationary actuator <NUM> and blade <NUM>.

<FIG> also shows an embodiment wherein the outer sheath <NUM> has a narrow portion <NUM>. The narrow portion <NUM> of the outer sheath <NUM> has a second inner volume <NUM> with a diameter smaller than the diameter of the first inner volume <NUM> of the outer sheath <NUM>. In one embodiment, the narrow portion <NUM> is tapered in a direction toward the distal end <NUM> of the actuator <NUM> and blade <NUM>, as shown in <FIG>. However, the narrow portion <NUM> does not need to be tapered in order to have a second inner volume <NUM> with a diameter smaller than the diameter of the first inner volume <NUM>. The narrow portion <NUM> having a second inner volume <NUM> with a smaller diameter aids in preventing the potential of the blade <NUM> from inadvertently becoming disconnected from the actuator <NUM> (in the two-piece embodiment). The narrow portion <NUM> can also provide an a-traumatic tip to prevent damage at or near the surgical site based on its shape and/or being composed of non-metal material, such as PEEK. In the event of a failure of the notches <NUM>, <NUM> securing the blade <NUM> to the actuator <NUM>, the narrow portion <NUM> and the second inner volume <NUM> maintain the blade <NUM> within the outer sheath <NUM> as opposed to falling from the device <NUM>.

Turning briefly to <FIG>, there is shown a close-up perspective view schematic representation of an alternative illustrative embodiment of the distal end <NUM> of the outer sheath <NUM>. In the depicted embodiment, the distal end <NUM> does not have a narrow portion <NUM>. The distal end <NUM> of the outer sheath <NUM> has an insert <NUM>. The insert <NUM> is preferably composed of non-metal material, such as PEEK. The insert <NUM> provides an a-traumatic tip to prevent damage at or near the surgical site. For example, the insert <NUM> is configured to prevent damage to cartilage structures within a joint space. <FIG> shows the blade <NUM> recessed within the insert <NUM> to allow for introduction of the outer sheath <NUM> and the blade <NUM> into the surgical site (e.g., joint space) either with or without a cannula.

Referring now to <FIG>, there are shown cutaway side view schematic representations of an illustrative embodiment of the retractable surgical cutting device of <FIG> in the retracted and extended positions, respectively. The handle <NUM> comprises a drive mechanism <NUM> therein, which facilitates movement of the actuator <NUM> and blade <NUM> longitudinally in both directions along an x-axis within the outer sheath <NUM>. In the embodiment shown in <FIG>, the drive mechanism <NUM> comprises a pair of springs. The pair of springs includes an extension spring <NUM> and a flat spring <NUM> (or thin metal piece). In the depicted embodiment, the extension spring <NUM> is a coil spring and the flat spring <NUM> is a leaf spring. Numerous combinations of springs may be utilized to facilitate movement of the actuator <NUM> along the first channel <NUM>.

Still referring to <FIG>, the extension spring <NUM> is connected at a proximal end <NUM> of the first channel <NUM> within the handle <NUM>. The extension spring <NUM> may be attached via a screw or other connector. The free end of the extension spring <NUM> is connected to the actuator <NUM>. The actuator <NUM> extends through the first channel <NUM> over a receptacle <NUM> in the handle <NUM>, which extends from and is connected to the first channel <NUM>. The flat spring <NUM> is attached to the receptacle <NUM> via a screw or other connector. As shown in the depicted embodiment, both the extension spring <NUM> and the flat spring <NUM> extend longitudinally along the x-axis.

In one embodiment for assembling the device <NUM>, the proximal end <NUM> of the actuator <NUM> is first attached to the switch <NUM> and hooked onto the extension spring <NUM>. The extension spring <NUM> is then looped over a post located within the first channel <NUM> of the handle <NUM>. The flat spring <NUM> is positioned near a distal end <NUM> of the handle <NUM>, under the actuator <NUM>. The outer sheath <NUM> is attached to the handle <NUM> and the two pieces <NUM>, <NUM> of the handle <NUM> are assembled together.

Still referring to <FIG>, the extension spring <NUM> is indirectly connected to the switch <NUM> via the actuator <NUM> to facilitate longitudinal movement of the actuator <NUM> along the x-axis. The switch <NUM> extends from the exterior of the handle <NUM> through a second channel <NUM>. The second channel <NUM> extends from the exterior of the handle <NUM> into the first channel <NUM>. An illustrative embodiment of the switch <NUM> is shown in <FIG>. The switch <NUM> comprises an outer portion <NUM> connected to a body portion <NUM>. In the depicted embodiment, the outer portion <NUM> has a width which is greater than the width of the second channel <NUM> such that the outer portion <NUM> of the switch <NUM> is maintained on the exterior of the handle <NUM> (as shown in <FIG>). Also shown in the embodiment of <FIG>, the switch <NUM> has an actuator slot <NUM> configured for connection to the actuator <NUM>.

Still referring to <FIG>, the body portion <NUM> of the switch <NUM> has a pair of flanges <NUM>. The pair of flanges <NUM> facilitates movement of the body portion <NUM> of the switch <NUM> along the second channel <NUM>. In particular, the flanges <NUM> and the outer portion <NUM> of the switch <NUM> are dimensioned to fit around the interior of the handle <NUM> on either side of second channel <NUM> such that the outer portion <NUM> is above the second channel <NUM> and the flanges <NUM> are below the second channel <NUM> when the device <NUM> is in the retracted position, as shown in <FIG>. In the retracted position, the blade <NUM> is entirely within the outer sheath <NUM>. The fit of the outer portion <NUM> and the flanges <NUM> around the handle <NUM> on either side of second channel <NUM> should be loose enough to allow the switch <NUM> to slide in the longitudinal direction along the x-axis to move the device <NUM> to the extended position.

In use, when the switch <NUM> is moved toward the distal end <NUM> of the handle <NUM>, the extension spring <NUM> is extended and the switch <NUM> contacts the flat spring <NUM>, as shown in <FIG>. The flat spring <NUM> forces the switch <NUM> upward and out through the second channel <NUM> until at least one of the flanges <NUM> contacts a shelf <NUM> within the second channel <NUM> of the handle <NUM>. In particular, when the switch <NUM> is forced upward and away from the flat spring <NUM>, at least one of the flanges <NUM> on the switch <NUM> interfaces with the shelf <NUM> in the handle <NUM> thereby locking the switch <NUM> in place. The shelf <NUM> prevents the switch <NUM> from disconnecting or otherwise falling out from the second channel <NUM> of the handle <NUM>. When the switch <NUM> is locked in place against the shelf <NUM>, the device <NUM> is locked in the extended position. In the extended position, the blade <NUM> is extended from the outer sheath <NUM> and exposed for use.

After use, the switch <NUM> is pressed downward toward the flat spring <NUM> and moved proximally along the second channel <NUM>. By pressing the switch <NUM> downward, the flange <NUM> is released from the shelf <NUM> and the switch <NUM> is unlocked or free for movement proximally within the second channel <NUM>. In one embodiment, the device <NUM> emits an audible indication that the switch <NUM> has reached the locked and/or unlocked positions. For example, the interfacing between the flange <NUM> and the shelf <NUM> may cause an audible clicking sound.

In the embodiment shown in <FIG>, the switch <NUM> is located on a top side <NUM> of the device <NUM>. However, the switch <NUM> can be configured to be positioned at any other location on the device <NUM>, such as the switch <NUM> in <FIG>, for example. The embodiment of the switch <NUM> depicted in <FIG> also comprises an outer portion <NUM> connected to a body portion <NUM>. The body portion <NUM> of the switch <NUM> has a pair of flanges <NUM>, which facilitate movement of the body portion <NUM> of the switch <NUM> along a second channel <NUM>, similar to the embodiment shown in <FIG>.

The switch <NUM> in <FIG> can be positioned on a bottom side <NUM> of the device <NUM>, as shown in <FIG>. In the embodiment depicted in <FIG>, the switch <NUM> is easily accessible to the user as the switch <NUM> is located near the grip of the user on the handle <NUM> of the device <NUM>. The first channel <NUM>, which is connected to the actuator <NUM> in the embodiment shown in <FIG>, extends through the switch <NUM> in the embodiment shown in <FIG>. Specifically, the body portion <NUM> of the switch <NUM> in <FIG> comprises an aperture <NUM> for receiving and containing the actuator <NUM>. In the depicted embodiment, the outer sheath <NUM> is connected to the switch <NUM>, at the outer perimeter of aperture <NUM>, for example.

Referring now to <FIG>, there is shown a side view of an illustrative embodiment of the device in <FIG> in the retracted position. In the retracted position, the blade <NUM> is contained within the outer sheath <NUM> and the switch <NUM> is not actuated. From the retracted position, pressing (i.e., actuating) the switch <NUM> moves the switch <NUM> proximally within the handle <NUM>. As the switch <NUM> moves, the switch <NUM> pulls the connected outer sheath <NUM> proximally while the actuator <NUM> remains stationary. Proximal movement of the outer sheath <NUM> exposes the blade <NUM> at the distal end <NUM> of the actuator <NUM> for use, as shown in <FIG>.

Referring now to <FIG>, there are shown various views of an alternative embodiment for the drive mechanism <NUM>. In the embodiment depicted in <FIG>, the drive mechanism <NUM> is a rack and pinion assembly comprising the switch <NUM>, a gear <NUM>, and a rack <NUM> (or treads) on the outer sheath <NUM>. As shown in <FIG>, the outer sheath <NUM> extends through the first channel <NUM>. The rack <NUM> on the outer sheath <NUM> interfaces with the gear <NUM> within the handle <NUM>, which also interfaces with a bottom side <NUM> of the switch <NUM>. The bottom side <NUM> of the switch <NUM> also comprises a rack (or treads), which engages the gear <NUM>. From a retracted position, the switch <NUM> is moved distally, which causes the bottom side <NUM> of the switch <NUM> to rotate the gear <NUM>. Rotation of the gear <NUM> pulls the outer sheath <NUM> proximally by the rack <NUM>. As the outer sheath <NUM> moves proximally into the handle <NUM>, the actuator <NUM> remains stationary causing exposure of at least a portion of the blade <NUM>, as shown in <FIG>. According to another embodiment, a locking mechanism is provided which can be actuated by a user to selectively stop the ability of the gear <NUM> to rotate over the rack <NUM> (and be reversed/released to allow rotation of the gear <NUM> over the rack <NUM>). Such a locking mechanism can include a push button, a lever arm, detent or other mechanism, for example, which blocks the gear <NUM> from rotating over the rack <NUM> (as should be understood by a person of ordinary skill in the art in conjunction with a review of this disclosure).

In another embodiment, shown in <FIG>, the drive mechanism <NUM> is a sliding wire assembly. The sliding wire assembly comprises the switch <NUM>, a wire (or flat stock) <NUM>, and the outer sheath <NUM>. In the depicted embodiment, the wire <NUM> is attached to both the switch <NUM> and the outer sheath <NUM>, and is loosely contained by screws, a molded channel, or other known connectors. <FIG> shows the device <NUM> comprising the sliding wire assembly in the retracted position. As the switch <NUM> is moved distally toward the distal end <NUM> of the actuator <NUM> (as shown in <FIG>), the wire <NUM> moves around the screws or within the molded channels, which in turn moves the outer sheath <NUM> proximally in a direction opposing the direction of movement of the wire <NUM> and the switch <NUM>. As the outer sheath <NUM> moves proximally, the actuator <NUM> remains stationary and the blade <NUM> is exposed for use. In one embodiment, the wire or flat stock <NUM> is composed of stainless steel. However, any other suitable compositions may be used.

An embodiment of an actuation and locking mechanism of a retractable surgical cutting device will now be described with reference to additional figures. The manually actuated and retractable surgical device can have some or all of the configurations and attributes of the retractable surgical device described above, some of which will not be repeated below. The main difference is the actuation and locking mechanism, which can be used on conjunction with the previously described embodiments of the retractable surgical device in place of any previously described actuation and/or locking mechanism.

In brief, an embodiment of the actuation and locking mechanism is a Geneva-style actuation/drive and locking mechanism (as should be understood by a person of ordinary skill in the art in conjunction with this disclosure). The Geneva drive and locking mechanism is configured to translate a continuous linear and rotational movement into intermittent rotational and linear movement.

Referring now to <FIG>, there is shown a side view schematic representation of an illustrative additional embodiment of a retractable surgical cutting device <NUM>. The device <NUM> extends along a central longitudinal axis and comprises a handle <NUM> connected to an outer sheath <NUM>, which extends to a distal blade <NUM>. The blade <NUM> is selectively extended and retracted upon actuation (e.g., sliding in a proximal or distal direction along an axis that is parallel to the central longitudinal axis of the device) of an actuator (here, a button) <NUM> on the handle <NUM>, as will be explained in detail later. As shown in <FIG>, the handle <NUM> can include thumb and finger grooves such that the shape of the handle <NUM> is ergonomic. The ergonomic design of the handle <NUM> provides increased control of the device <NUM> for its intended use. In other embodiments, the handle <NUM> may have fewer grooves or no grooves entirely. In some embodiments, the handle <NUM> is composed of plastic; however, the handle <NUM> may be composed of stainless steel or other traditional materials suitable for surgical devices.

Still referring to <FIG>, the handle <NUM> of the device <NUM> can be comprised of two pieces (or halves of a clamshell), a first piece <NUM> and a second piece <NUM>, and can have one or more channels therethrough. The button <NUM> can move distally along an axis parallel to the central longitudinal axis and toward the distal end of the instrument, and can be slid proximally along the axis parallel to the central longitudinal axis and toward the proximal end of the device. At the end of the range of motion of button <NUM> (distally and proximally on the top surface of the device), there can be small finger-like projections <NUM>, that are configured to provide a minimal amount of friction - only what is necessary to hold the button <NUM> at the distal and proximal extremities of its travel (it does not restrain the components of the mechanism that are to be actuated). In this embodiment shown, the operation is to alternately actuate the retraction of a protective sheath <NUM>, from shielding a blade <NUM>, at the distal end of the sheath. Alternatively, actuation of the blade <NUM> beyond the distal end of the sheath <NUM> and retraction of blade <NUM> into the sheath <NUM> (partially and not fully, or fully) is also contemplated.

Turing to <FIG>, there is shown a side view open schematic representation of an illustrative embodiment of a retractable surgical cutting device <NUM> with the second piece <NUM> of the handle <NUM> removed, according to an embodiment. <FIG> shows the main components of the actuation and locking mechanism of an embodiment. Any number of medical devices could incorporate such an actuation and locking mechanism including, but not limited to, graspers, suture passers, cutting instruments, snipping instruments, etc. Note that the shaft <NUM> of the cutting blade <NUM>, is rigidly positioned/integrated into the body <NUM> at its proximal end, by mounting a point <NUM> of the shaft <NUM> into the interior of the handle <NUM>, essentially unitizing the two and preventing the shaft <NUM> (and thus, the blade <NUM>) from moving. In accordance with an embodiment, the actuation and locking mechanism (as described below) is configured to move the sheath <NUM> proximally and distally along the central longitudinal axis, alternatingly extending it distally and preferably fully over the cutting blade <NUM> (to protect the user and the patient when not in use), and retracting it proximally to expose the cutting blade <NUM> for use (essentially, unsheathing it).

The actuation and locking mechanism <NUM> of an embodiment is partially shown in <FIG> and more fully shown in <FIG>. The actuation and locking mechanism <NUM> is a Geneva-style actuation/drive and locking mechanism, which is laid out in a linear fashion to create two or more stopping points where component(s) that are moved are locked in position, without any further action of the user beyond the normal user interface, in this case, sliding the button <NUM>. The button <NUM> is connected (directly molded, or indirectly) to a gear rack <NUM>, which include teeth that mesh with the teeth of a pinion gear <NUM> positioned inside handle <NUM>. Pinion gear <NUM> is connected (directly or indirectly) to Geneva wheel <NUM>, which includes a pin <NUM> and a semicircular cam <NUM>. As shown, the pinion gear <NUM> is centrally positioned adjacent to a first surface of the Geneva wheel <NUM>, the pin <NUM> is positioned on the first surface and close/adjacent to the perimeter of the Geneva wheel <NUM>, and the semicircular cam <NUM> is positioned on the first surface opposite to the pin <NUM> and a predetermined distance from the perimeter of the wheel <NUM> (so that the Geneva wheel is optimally workable, as should be understood by a person of ordinary skill in the art in conjunction with a review of this disclosure).

The button <NUM>, gear rack <NUM>, pinion gear <NUM>, wheel <NUM>, pin <NUM> and semicircular cam <NUM> act as a drive mechanism for a slider <NUM>. As shown in <FIG>, for example, slider <NUM> includes a slot <NUM> positioned between two semicircular grooves/concave surfaces <NUM> and <NUM>, respectively (multiple slots and/or more than <NUM> semicircular grooves/concave surfaces <NUM> and <NUM> are contemplated). The slot <NUM> is configured to receive the pin <NUM> and the two semicircular grooves/concave surfaces <NUM> and <NUM> are configured to receive the semicircular cam <NUM>, upon the movement of the drive mechanism. The slider <NUM> is moveably attached to the sheath <NUM>, such that when the slider <NUM> is moved in the proximal or distal direction along the central longitudinal axis by the drive mechanism (the sliding in either direction of button <NUM> moves the gear rack <NUM> in the same direction, which causes pinion gear <NUM> to rotate and spin the wheel <NUM> to move the semicircular cam <NUM> into one or more of the semicircular grooves/concave surfaces <NUM> and <NUM> and the pin <NUM> into the slot <NUM>, causing the slider <NUM> to be moved proximally or distally), the sheath <NUM> moves in the same direction of the slider <NUM> to expose or cover the blade <NUM> (the opposite connections of the sheath <NUM> and the shaft <NUM> of the blade <NUM> (connected to the slider) would result in similar movement of the shaft <NUM> and blade <NUM>, and fixation of the sheath <NUM> (connected to the interior surface of the handle)).

As discussed in more detail with respect to <FIG>, when pin <NUM> engages slot <NUM> of slider <NUM>, pin <NUM> is configured to drive the slider <NUM> (and sheath <NUM>) in a proximal or distal direction (depending on movement of the button <NUM>). When the pin is positioned out of the slot <NUM> and the semicircular cam <NUM> engages either semicircular grooves/concave surfaces <NUM> and <NUM>, the slider <NUM> (and sheath <NUM>) is in a "pause" unmoving/locked configuration and position, while the button <NUM> continues to move (and the drive mechanism as a whole is still being engaged). The amount of button <NUM> travel required to pass slider <NUM>, from one position to another can by controlled by characteristics of the teeth on the pinion gear <NUM>, and/or on the gear rack <NUM>. The magnitude of travel of the slider <NUM> can be altered with the radius of rotation of the pin <NUM>.

Turing to <FIG>, there is shown a side view schematic representation of an illustrative embodiment of the drive mechanism and slider of the retractable surgical cutting device <NUM> in accordance with an embodiment. As shown in <FIG>, a user has interfaced with the button <NUM>, moving it all the way in the direction shown (distally). This movement of button <NUM> has caused gear rack <NUM> to move in the same direction with the button <NUM>. Pinion gear <NUM> has rotated clockwise as shown, per its interface with gear rack <NUM>. The semicircular cam <NUM> of Geneva wheel <NUM> is shown nested in the semicircular groove <NUM>, locking the slider <NUM> into position after its movement in the direction of actuation (proximally), shown with the directional arrow. Notably, the locking of slider <NUM> occurred with no user action other than sliding the button <NUM>.

Turing to <FIG>, there is shown a side view schematic representation of an illustrative embodiment of the drive mechanism and slider of the retractable surgical cutting device <NUM> in accordance with an embodiment. <FIG> shows the drive mechanism and slider <NUM> at the midpoint between two stop/locked positions. Pin <NUM> on Geneva wheel <NUM> is positioned in slot <NUM>. As the wheel <NUM> is rotated by pinion gear <NUM> interacting with gear rack <NUM>, it passes (pursuant to the drive functionality of the pin's <NUM> engagement with slot <NUM>) the slider <NUM> from one position to another (most distal position to most proximal position, and vice versa). Note that semicircular cam <NUM> on the wheel <NUM> has rotated out of the way of the slot <NUM> and semicircular grooves <NUM> of slider <NUM>, as to not impede the movement of slider <NUM> in the proximal direction (from the position shown in <FIG>).

Referring to <FIG>, there is shown a side view schematic representation of an illustrative embodiment of the drive mechanism and slider of the retractable surgical cutting device <NUM> in accordance with an embodiment. As shown in <FIG>, the drive mechanism has been fully actuated in the opposite direction shown in <FIG>. The semicircular cam <NUM> of wheel <NUM> is now nested in semicircular groove <NUM>, not in semicircular groove <NUM> as shown earlier in <FIG>. The slider <NUM> is now actuated and locked into the "distal" position by no user action other than sliding the button <NUM> in the proximal direction.

While any number of materials could be used to fabricate such an actuation and locking mechanism, it is anticipated that typically the mechanism as a whole, and it's housing can be fabricated of injection molded plastic of reasonable strength, and that the aspects of the medical instrument to be actuated, such as cutters, blades, snippers, suture passers, etc, can be made of surgical grade metals such as stainless steel and Nitinol.

The inventors contemplate various alternative embodiments of the actuation and locking mechanism described herein. For example, as previously noted, a slider <NUM> with a plurality of slots <NUM> and/or more than two semicircular grooves <NUM> and <NUM>, in order to create more than two paused/locked stopping locations for a mechanism's actuation where intermediate stages of movement that are locked in place are desired.

The embodiment of the actuation and locking mechanism described herein creates a "reversing" effect, where direction of the button <NUM>, in one direction generates motion of the slider <NUM> in the opposite direction. This is because the gear rack <NUM> and the slider <NUM> are on opposite sides of the pinion gear <NUM>. An alternative embodiment can have the gear rack <NUM>, and slider <NUM> on the same side of the pinion gear <NUM>, eliminating the reversing effect and causing the slider <NUM> to move in the same direction as the button <NUM>.

While the of the actuation and locking mechanism described herein has a linear relationship between button <NUM> motion and pinion gear <NUM> rotation, an alternate embodiment is possible where pinion gear <NUM> is non-circular and gear rack <NUM> is a non-linear shape suitable for interfacing with a non-circular pinion gear. This would result in an alteration of the motion profile of the slider <NUM> with respect to movement of the button <NUM>.

The described embodiment of the actuation and locking mechanism shows one rack <NUM>, one pinion gear <NUM>, and one Geneva wheel <NUM>, acting on one slider <NUM>. An alternate embodiment is possible where more than one gear rack is moved by a single button <NUM>, and those gear racks interact with more than more than one pinion gear, more than one Geneva wheel, and more than one slider, to actuate more than one mechanism, and that the relative timing of these systems can cause multiple motions that can be orchestrated in a particular sequence to perform more complicated systems of actuations. For example, if one desired a sheathed snipper where the cutting elements of the snipper could only possibly actuate and de-actuate after the sheath was moved to a fully retracted position and never when the sheath was extended, a single button <NUM> could move two gear racks that interact with two pinion gears, two Geneva wheels, and two sliders, where the two systems could be timed with respect to each other as to be out of phase with each other in order to orchestrate the desired sequence of motions needed to ensure that snipper actuation and de-actuation could only occur after sheath retraction had occurred (as should be understood by a person of ordinary skill in the art in conjunction with a review of this disclosure). This timing between the two systems actuated by the same button could be achieved by altering any number of design parameters, such as the angular timing of each pinion's teeth with respect to its respective rack, alternating the pitch diameter and/or number of teeth on each pinion gear, alternating the magnitude (radius about which the pin rotates) of the motion developed by pin <NUM>, alternating the number of slots and semicircular grooves in the sliders (as should be understood by a person of ordinary skill in the art in conjunction with a review of this disclosure). While any number of variations could be utilized to achieve multiple varying motion profiles and orchestrate those multiple motion profiles with respect to each other, the essence of this embodiment is that multiple Geneva-based mechanisms actuated by a single button can generate multiple motion profiles to create more complex systems of coordinated motions between multiple functionalities incorporated in a product (as should be understood by a person of ordinary skill in the art in conjunction with a review of this disclosure).

In an alternate embodiment, the linear motion of the gear rack <NUM> acted upon by a button <NUM> is replaced with an arc-shaped gear rack actuated by a lever, which causes the teeth of the arc-shaped gear rack to rotate the pinion gear <NUM>.

All definitions, as defined and used herein, should be understood to control over dictionary definitions, definitions in documents, and/or ordinary meanings of the defined terms.

While various embodiments have been described and illustrated herein, those of ordinary skill in the art will readily envision a variety of other means and/or structures for performing the function and/or obtaining the results and/or one or more of the advantages described herein, and each of such variations and/or modifications is deemed to be within the scope of the embodiments described herein. More generally, those skilled in the art will readily appreciate that all parameters, dimensions, materials, and configurations described herein are meant to be exemplary and that the actual parameters, dimensions, materials, and/or configurations will depend upon the specific application or applications for which the teachings is/are used. Those skilled in the art will recognize, or be able to ascertain using no more than routine experimentation, many equivalents to the specific embodiments described herein. It is, therefore, to be understood that the foregoing embodiments are presented by way of example only and that, within the scope of the appended claims, embodiments may be practiced otherwise than as specifically described and claimed. Embodiments of the present disclosure are directed to each individual feature, system, article, material, kit, and/or method described herein. In addition, any combination of two or more such features, systems, articles, materials, kits, and/or methods, if such features, systems, articles, materials, kits, and/or methods are not mutually inconsistent, is included within the scope of the present disclosure.

It will be further understood that the terms "comprise" (and any form of comprise, such as "comprises" and "comprising"), "have" (and any form of have, such as, "has" and "having"), "include" (and any form of include, such as "includes" and "including"), and "contain" (any form of contain, such as "contains" and "containing") are open-ended linking verbs. As a result, a method or device that "comprises", "has", "includes" or "contains" one or more steps or elements. Likewise, a step of method or an element of a device that "comprises", "has", "includes" or "contains" one or more features possesses those one or more features, but is not limited to possessing only those one or more features. Furthermore, a device or structure that is configured in a certain way is configured in at least that way, but may also be configured in ways that are not listed.

Claim 1:
A retractable surgical cutting device (<NUM>), comprising:
a handle (<NUM>) including a handle proximal end, a handle distal end, an outer surface, and an internal space, the handle (<NUM>) extending along a central longitudinal axis;
an actuator (<NUM>) located and movable in a first direction to a first actuator position and in a second direction to a second actuator position on the outer surface of the handle (<NUM>);
a sheath (<NUM>) extending along the central longitudinal axis and including a sheath proximal end and a sheath distal end, wherein the sheath proximal end is positioned within the internal space of the handle (<NUM>), and wherein the sheath (<NUM>) is configured to move in the first direction to a sheath first position, and is configured to move in a second direction to a sheath second position;
a shaft (<NUM>) at least partially positioned within the sheath (<NUM>) and extending along the central longitudinal axis and including a shaft proximal end (<NUM>) and a shaft distal end (<NUM>), wherein the shaft proximal end (<NUM>) is connected to the interior surface of the handle (<NUM>) and the shaft distal end (<NUM>) includes a blade (<NUM>); and
a drive and locking mechanism (<NUM>) connected to the actuator (<NUM>) and to the sheath (<NUM>) within the internal space of the handle (<NUM>),
characterized in that the drive and locking mechanism (<NUM>) is configured to move the sheath (<NUM>) in the first direction and lock the sheath (<NUM>) in the sheath first position in response to movement of the actuator (<NUM>) in the second direction, and wherein the drive mechanism (<NUM>) is configured to move the sheath (<NUM>) in the second direction and lock the sheath (<NUM>) in the sheath second position in response to movement of the actuator (<NUM>) in the first direction, wherein the locking is not performed by friction, but by a positive, mechanical, locking function