Rotation knobs for surgical instruments

A surgical instrument includes a housing having a shaft extending therefrom. The housing includes a nose having a neck and a base that defines a diameter greater than that of the neck. A rotation knob has a distal end defining a first aperture and a proximal end defining a second aperture, the apertures cooperating to define a lumen extending through the rotation knob that is configured to receive the shaft. The first aperture defines a diameter that generally approximates a diameter of the shaft. The rotation knob is transitionable between an at-rest position and a flexed position. In the flexed position, the second aperture is expanded to permit passage of the base of the nose into an interior of the rotation knob. In the at-rest position, the second aperture generally approximates the diameter of the neck to rotatably engage the rotation knob about the nose with the shaft extending therethrough.

BACKGROUND

1. Technical Field

The present disclosure relates to surgical instruments and, more particularly, to rotation knobs for surgical instruments having rotatable end effector assemblies.

2. Background of Related Art

As an alternative to open surgical instruments for use in open surgical procedures, many modern surgeons use endoscopic apparatus for remotely accessing tissue through smaller openings or incisions. As a direct result thereof, patients tend to benefit from less scarring, fewer infections, shorter hospital stays, less pain, less restriction of activity, and reduced healing time. A typical endoscopic instrument includes a housing, an end effector assembly, and a shaft interconnecting the housing and the end effector assembly. The housing includes one or more controls that are operable to control the end effector assembly such that the end effector assembly may be inserted through the opening in tissue and into the internal surgical site, while the housing remains externally disposed, allowing the surgeon to manipulate the housing controls to control operation of the end effector assembly within the internal surgical site.

An endoscopic surgical forceps, for example, includes a plier-like end effector assembly which relies on mechanical action between its jaw members to grasp, clamp and constrict vessels or tissue. Energy-based surgical forceps utilize both mechanical clamping action and energy, e.g., electrical energy, ultrasonic energy, light energy, thermal energy, etc., to treat tissue. In some procedures, once the tissue has been treated, the surgeon has to sever the tissue and, as such, many forceps have been designed which incorporate a knife or blade member that effectively severs the tissue after treating the tissue.

The housings of endoscopic surgical forceps typically include a movable handle for opening and closing the jaw members, a trigger for selectively advancing the knife or blade, and an actuator for controlling the supply of energy to the end effector assembly. Further, some handle assemblies incorporate a rotation assembly that is operable to selectively rotate the end effector assembly in order to position the end effector assembly as desired within the internal surgical site.

SUMMARY

As used herein, the term “distal” refers to the portion that is being described which is further from a user, while the term “proximal” refers to the portion that is being described which is closer to a user.

In accordance with one aspect of the present disclosure, a surgical instrument is provided. The surgical instrument includes a housing having a shaft extending distally therefrom. The shaft defines a longitudinal axis. The housing includes a nose disposed at a distal end thereof. The nose includes a neck extending distally from the housing and a base disposed at a distal end of the neck. The base defines a diameter that is greater than a diameter of the neck. The surgical instrument further includes a rotation knob having a distal end defining a first aperture and a proximal end defining one or more second apertures. The first aperture defines a diameter that generally approximates a diameter of the shaft. The first and second apertures cooperate to define a lumen extending longitudinally through the rotation knob. The lumen is configured to receive the shaft. The rotation knob is transitionable between an at-rest position and a flexed position. In the flexed position, the diameter of the second aperture is expanded to permit passage of the base of the nose through the second aperture and into an interior of the rotation knob. In the at-rest position, the second aperture defines a diameter that generally approximates the diameter of the neck of the nose to rotatably engage the proximal end of the rotation knob about the nose with the shaft extending through the lumen of the rotation knob.

In one aspect, the rotation knob includes one or more protrusions extending into the interior thereof. The protrusion(s) is configured to engage the shaft, e.g., cut-outs defined within the shaft, to engage the rotation knob and the shaft to one another.

In another aspect, the rotation knob includes a retaining ring configured to bias the rotation knob towards the at-rest position. The retaining ring may include an interruption defined therein that permits expansion of the retaining ring to thereby permit transitioning of the rotation knob between the at-rest and flexed positions.

In still another aspect, the rotation knob includes first and second pairs of proximal support walls. Each pair of proximal support walls cooperates to define one of the second apertures therethrough. In this configuration, the retaining ring may be disposed between the first and second pairs of proximal support walls.

In yet another aspect, the rotation knob includes a plurality of alternating flanges and recesses disposed on the outer periphery thereof. The alternating flanges and recesses are configured to facilitate grasping and rotating the rotation knob.

In still yet another aspect, an outer distal corner of the base of the nose defines an angled surface configured to facilitate transitioning of the rotation knob from the at-rest position to the flexed position to permit passage of the base through the one or more second apertures.

In another aspect, the rotation knob is monolithically formed as a single component.

In yet another aspect, the housing is formed from first and second housing parts. In this configuration, when the rotation knob is engaged about the nose of the housing, the rotation knob helps maintain the engagement of the first and second housing parts to one another.

In accordance with the present disclosure, another aspect of a surgical instrument is provided. The surgical instrument includes a housing having a shaft extending distally therefrom. The shaft defines a longitudinal axis. The housing includes a nose disposed at a distal end thereof. The nose includes a neck extending distally from the housing and a base disposed at a distal end of the neck. The base defines a diameter that is greater than a diameter of the neck. The surgical instrument further includes a rotation knob. The rotation knob has a distal end defining a first aperture and a plurality of radially-spaced fingers extending proximally from a proximal end of the rotation knob. The fingers each including a radially inwardly-extending tab disposed at a free end thereof. The tabs cooperate with one another to define a second aperture. The first aperture defines a diameter that generally approximates a diameter of the shaft. The first and second apertures cooperate to define a lumen extending longitudinally through the rotation knob that is configured to receive the shaft. The rotation knob is transitionable between an at-rest position and a flexed position. In the flexed position, the fingers are flexed radially outwardly to expand a diameter of the second aperture to permit passage of the base of the nose through the second aperture and into an interior of the rotation knob. In the at-rest position, the second aperture defines a diameter that generally approximates the diameter of the neck of the nose to rotatably engage the tabs of the fingers of the rotation knob about the nose, with the shaft extending through the lumen of the rotation knob.

In one aspect, the rotation knob includes one or more protrusions extending into the interior thereof. The protrusion(s) is configured to engage the shaft, e.g., a cut-out defined within the shaft, to engage the rotation knob and the shaft to one another.

In one aspect, the fingers are biased towards the at-rest position.

In another aspect, the rotation knob is monolithically formed as a single component.

In yet another aspect, the housing is formed from first and second housing parts. In this configuration, when the rotation knob is engaged about the nose of the housing, the rotation knob helps maintain the engagement of the first and second housing parts to one another.

In accordance with yet another aspect of the present disclosure, a surgical instrument is provided. The surgical instrument includes a housing and a shaft extending distally from the housing. The shaft defines a longitudinal axis and extends through an aperture defined within a distal surface of the housing. The shaft further includes a bushing disposed about the shaft towards a proximal end thereof. The surgical instrument further includes a rotation knob. The rotation knob includes a proximal end, a distal end, and a lumen extending longitudinally therethrough that is configured to receive the shaft. The rotation knob defines an internal cavity in communication with the lumen that is configured to receive the bushing therein. The rotation knob includes a plurality of radially-spaced fingers extending proximally from a proximal end thereof. The fingers each include a radially outwardly-extending tab disposed at a free end thereof. The tabs cooperating to define an outer peripheral diameter. The rotation knob is transitionable between a first at-rest position and a first flexed position, while the fingers are transitionable between a second at-rest position and a second flexed position. In the first flexed position, the rotation knob is flexed to expand a diameter of the lumen to permit passage of the bushing distally through the lumen and into the internal cavity of the rotation knob. In the first at-rest position, the diameter of the lumen generally approximates a diameter of the shaft to engage the bushing within the internal cavity. In the second flexed position, the fingers are flexed radially-inwardly such that the fingers are permitted to pass through the aperture defined within the distal surface of the housing. In the second at-rest position, the outer peripheral diameter defined by the tabs of the fingers is greater than a diameter of the aperture defined through the distal surface of the housing to rotatably engage the distal surface of the housing within a slot defined between the proximal end of the rotation knob and the tabs of the fingers, with the shaft extending through the lumen of the rotation knob.

In one aspect, the fingers are biased towards the second at-rest position.

In another aspect, the rotation knob is biased towards the first at-rest position.

In still another aspect, the rotation knob includes a plurality of alternating flanges and recesses disposed on the outer periphery thereof. The alternating flanges and recesses are configured to facilitate grasping and rotating the rotation knob.

In yet another aspect, the rotation knob and fingers are monolithically formed as a single component.

DETAILED DESCRIPTION

FIGS. 1-3show in detail the operating features and inter-cooperating components of one example of a surgical instrument, forceps10, configured for use in accordance with the present disclosure. Although the present disclosure is described with exemplary reference to forceps10, the present disclosure is equally applicable for use with any other suitable surgical instrument having a housing including one or more mechanical and/or electrical controls operable to control and/or manipulate an end effector assembly of the surgical instrument. For the purposes herein, forceps10is generally described.

Forceps10defines a longitudinal axis “X-X” and includes a housing20, a handle assembly30, a rotating assembly70, a trigger assembly80and an end effector assembly90. Forceps10further includes a shaft12having a distal end14configured to mechanically engage end effector assembly90and a proximal end16that mechanically engages housing20. Forceps10also includes cable2that connects forceps10to a generator (not shown) or other suitable power source, although forceps10may alternatively be configured as a battery powered instrument. Cable2includes wires (not shown) extending therethrough that have sufficient length to extend through shaft12in order to provide energy to at least one of the jaw members92and96of end effector assembly90.

With continued reference toFIGS. 1-3, handle assembly30includes a fixed handle50and a movable handle40. Fixed handle50is integrally associated with housing20and handle40is movable relative to fixed handle50. Rotating assembly70, as will be described in greater detail below, includes a rotation knob100that is rotatable in either direction about longitudinal axis “X-X” to rotate end effector assembly90about longitudinal axis “X-X.”

End effector assembly90is shown attached at a distal end14of shaft12and includes a pair of opposing jaw members92and96. More specifically, jaw members92,96are pivotably coupled to shaft12via pivot91. Each jaw member92,96includes an opposed, electrically conductive tissue sealing surface93,97, respectively. End effector assembly90is configured as a bilateral assembly, i.e., where both jaw member92and jaw member96are movable about pivot91relative to one another and to shaft12. However, end effector assembly90may alternatively be configured as a unilateral assembly, i.e., where one of the jaw members92,96is fixed relative to shaft12and the other jaw member92,96is movable about pivot91relative to shaft12and the fixed jaw member92,96. A knife assembly98is disposed within shaft12and a knife channel95is defined within one or both jaw members92,96to permit reciprocation of a knife blade99therethrough, e.g., via activation of trigger82of trigger assembly80, to cut tissue grasped between jaw members92,96.

Continuing with reference toFIGS. 1-3, housing20houses the internal working components of forceps10and is formed from first and second cooperating housing parts20a,20b. Housing halves20a,20bmay be snap-fit, or otherwise engaged to one another to form housing20. Movable handle40of handle assembly30extends into housing20, ultimately connecting to a drive assembly32that, together, mechanically cooperate to impart movement of jaw members92and96between a spaced-apart position and an approximated position to grasp tissue between sealing surfaces93,97of jaw members92,96, respectively. More specifically, movable handle40includes a pair of driving flanges34that extends upwardly into housing20on either side of drive assembly32, ultimately pivotably coupling to housing20via pivot35. Driving flanges34are received within mandrel36of drive assembly32, which is disposed about proximal end38of drive bar37, while jaw members92,96are pivotably coupled to distal end39of drive bar37. Due to this configuration, upon pivoting of movable handle40relative to fixed handle50, driving flanges34are pivoted about pivot35, thereby urging mandrel36and drive bar37to translate longitudinally along longitudinal axis “X-X” and through shaft12to pivot jaw members92,96between the spaced-apart and approximated positions. As shown inFIG. 1, movable handle40is initially spaced-apart from fixed handle50and, correspondingly, jaw members92,96are in the spaced-apart position. Movable handle40is depressible from this initial position to a depressed position corresponding to the approximated position of jaw members92,96.

With continued reference toFIGS. 1-3, in conjunction withFIG. 5C, rotation knob100is disposed about both proximal end16of shaft12and nose22of housing20and, as mentioned above, is rotatable in either direction about longitudinal axis “X-X” to rotate end effector100about longitudinal axis “X-X.” Shaft12includes a pair of cut-outs19defined within opposed sides18thereof at proximal end16of shaft12and rotation knob100includes a pair of protrusions102shaped complementarily to cut-outs19such that, upon positioning of rotation knob100about proximal end16of shaft12, protrusions102are received within cut-outs19to engage rotation knob100and shaft12to one another. With rotation knob100and shaft12engaged to one another, rotation knob100may be rotated about longitudinal axis “X-X” to effect corresponding rotation of shaft12and end effector assembly90about longitudinal axis “X-X.”

Nose22of housing20is configured to accept proximal end104of rotation knob100thereon to permit rotatable coupling of rotation knob100and housing20to one another. Nose22of housing20includes a neck23extending distally from body portion21of housing20and a distal base25disposed at free end24of neck23. Neck23defines a reduced diameter as compared to distal base25of nose22such that, as will be described below, when proximal end104of rotation knob100is disposed about neck23, rotation knob100is retained in fixed longitudinal position relative to nose22between body portion21of housing20and distal base25of nose22. The specific features and configuration of rotation knob100and other embodiments of rotation knobs configured for use with forceps10are described in greater detail below.

Turning now toFIGS. 4A-4Eand5A-5C, rotation knob100defines a generally conically-shaped configuration having a minimum diameter at distal end106thereof and a maximum diameter at proximal end104thereof, although other configurations are also contemplated. Rotation knob100includes a shell110defining the conically-shaped configuration of rotation knob100and includes a generally hollow interior112, a distal wall120defining distal end106of rotation knob100, and first and second sets of proximal support walls130,140defining proximal end104of rotation knob100. Distal wall120defines an aperture122therethrough that generally approximates the dimensions of shaft12such that shaft12is permitted to pass therethrough. Walls132,134of the first set of proximal support walls130extend inwardly from opposed sides of shell110and each define opposed surface133,135, respectively. Surfaces133,135may define curvate configurations (or any other suitable configurations) that cooperate to define an aperture136therebetween that is substantially aligned with aperture122defined through distal wall120. Aperture136, in its at-rest position, generally approximates the dimensions of neck23of nose22, such that proximal end104of rotation knob100may be disposed about nose22of housing20, as will be described in greater detail below. Walls142,144of the second set of proximal support walls140are spaced-apart from walls132,134of the first set of proximal support walls130to define an annular slot150therebetween. Walls142,144of the second set of proximal support walls140, similar to the first set of proximal support walls130, extend inwardly from opposed sides of shell110and each define an opposed surface143,145, respectively, e.g., a curvate surface (although other configurations are contemplated), that cooperate to define an aperture146that is substantially aligned with apertures122and136. Similar to aperture136, aperture146, in its at-rest position, generally approximates the dimensions of neck23of nose22, such that proximal end104of rotation knob100may be rotatably engaged about nose22of housing20, as will be described in greater detail below. Apertures122,136,146together cooperate to define a lumen160extending longitudinally though rotation knob100. Lumen160is configured to receive shaft12therethrough, thus permitting rotation knob100to be disposed about shaft12in a substantially at-rest position, as will be described below.

With continued reference toFIGS. 4A-4Eand5A-5C, rotation knob100includes a plurality of alternating flanges114and recesses116annularly disposed about the outer periphery of shell110towards proximal end104of rotation knob100(although other configurations are contemplated) to facilitate grasping and rotating rotation knob100. Rotation knob100is monolithically formed as a single component and may be formed from any suitable material, e.g., biocompatible polymer(s), that provides at least some degree of flexibility to permit engagement of rotation knob100about nose22of housing20, as will be described below. Further, shell110may be formed from a relatively thin material to facilitate flexing of shell110for engaging (and disengaging) rotation knob100about nose22of housing20, while distal wall120and the sets of proximal support walls130,140provide strength and support to rotation knob100. Rotation knob100may also include a plurality of cut-outs118defined annularly about shell110at proximal end104thereof to provided increase flexibility to shell110, e.g., to facilitate the outward-flexing of proximal end104of shell110such that shell110may be positioned about nose22.

Continuing with reference toFIGS. 4A-4Eand5A-5C, shell110includes a pair of opposed protrusions102extending inwardly into hollow interior112of shell110that are configured to engage opposed cut-outs19defined within shaft12to engage rotation knob100and shaft12to one another. Protrusions102extend into lumen160defined through rotation knob100and are longitudinally disposed between distal wall120of rotation knob100and first set of proximal support walls130of rotation knob100. Rotation knob100further includes a retaining ring180housed within annular slot150defined between the sets of proximal support walls130,140. Retaining ring180is secured within annular slot150via flanges137,139of walls132,134and flanges147,149of walls147,149, although retaining ring180may otherwise be secured within annular slot150in any suitable fashion, e.g., mechanical engagement, friction-fitting, adhesion, etc.

As best shown inFIG. 4E, retaining ring180is formed from wire in a substantially ring-shaped configuration defining an interruption182that provides resilient flexibility to retaining ring180, e.g., to permit radial expansion and contraction of ring180. The wire forming retaining ring180may define a circular, oval, square, star-shaped, or any other suitable cross-sectional configuration. Alternatively, retaining ring180may be formed from any other suitable resiliently flexible material and/or may define any other suitable configuration that provides resilient flexibility to retaining ring180. As will be described below, the resiliently flexible configuration of retaining ring180biases retaining ring towards an at-rest or contracted condition that, in turn, biases rotation knob100towards an at-rest, or un-flexed position (seeFIG. 5C).

Turning now toFIGS. 5A-5C, in conjunction with FIGS.1and4A-4E, the assembly of rotation knob100on a surgical instrument, e.g., forceps10, and the use of rotation knob100in conjunction with forceps10to effect rotation of end effector assembly90is described. As will become apparent in view of the following, the configuration of rotation knob100permits efficient assembly and disassembly of rotation knob100on forceps10without requiring additional tools for assembly, without requiring multiple components cooperating to form rotation knob100, and without compromising the integrity of rotation knob100.

Initially, as shown inFIG. 5A, in conjunction withFIGS. 4A-4E, rotation knob100is slid proximally over end effector assembly90with end effector assembly90passing through lumen160defined through shell110of rotation knob100. As mentioned above, lumen160is configured to receive shaft12therethrough such that rotation knob100may be easily slid proximally along shaft12towards housing20. Lumen160is configured to permit passage of shaft12therethrough without requiring substantial flexing of rotation knob100such that, at this point, shell110and retaining ring180of rotation knob100remain disposed in their respective at-rest positions (the at-rest position of rotation knob100). Upon reaching proximal end16of shaft12, with rotation knob100disposed in the at-rest position, rotation knob100is inhibited from being translated further proximally due to the abutment of the second set of proximal support walls140of rotation knob100and distal base25of nose22of housing20. That is, distal base25of nose22of housing20defines a diameter larger than the at-rest diameter of lumen160of shell110of rotation knob100such that distal base25is inhibited from passing through lumen160when rotation knob100is disposed in the at-rest position. Thus, in order to permit passage of proximal end104of rotation knob100proximally beyond distal base25of nose22and into position about neck23of nose22, rotation knob100is must flex from the at-rest position to a flexed position, thereby increasing the diameter of lumen160so as to permit passage of distal base25of nose22therethrough.

As shown inFIG. 5B, in conjunction withFIGS. 4A-4E, in order to permit passage of rotation knob100over distal base25of nose22, proximal end104of rotation knob100is flexed radially outwardly to expand lumen160to a sufficient diameter to permit passage of distal base25therethrough. That is, proximal end104of shell110is flexed radially outwardly such that walls132,134of the first set of proximal support walls130are moved apart from one another and such that walls142,144of the second set of proximal support walls140are likewise moved apart from one another to increase the diameter of apertures136,146, respectively, and, thus, the portion of lumen160extending through proximal end104of rotation knob100. Upon outward flexing of proximal end104of shell110, retaining ring180is likewise expanded against its bias to permit expansion of apertures136,146. Further, distal outer corner26of distal base25of nose22may define an angled surface27to facilitate outward flexing of shell110of rotation knob100as rotation knob100is urged proximally about distal base25of nose22, e.g., angled surface27of distal base25permits proximal end104of rotation knob100to cam therealong towards the flexed position.

Rotation knob100, in this flexed position, is advanced further proximally until the first and second sets of proximal support walls130,140, respectively, of rotation knob100are disposed proximally of distal base25of nose22and are positioned adjacent to neck23of nose22. In this position, as shown inFIG. 5C, distal base25of nose22is disposed within hollow interior112of shell110longitudinally between distal wall120and the first set of proximal support walls130. Upon achieving this position, with distal base25no longer disposed between the opposed walls132,134and142,144of first and second sets of proximal support walls130,140, respectively, and under the bias of retaining ring180and shell110, proximal end104of rotation knob100is returned back towards the at-rest position (wherein apertures136,146are returned towards their at-rest diameters) such that walls132,134and142,144are approximated, or clamped about neck23of nose22. In this position, proximal end104of rotation knob100is engaged about nose22of housing20, i.e., neck23of nose22extends through apertures136,146defined by first and second sets of proximal support walls130,140, respectively, while distal end106of rotation knob100is disposed about proximal end16of shaft12, i.e., proximal end16of shaft12extends through aperture122defined through distal wall120of rotation knob100.

With continued reference toFIG. 5C, in conjunction withFIGS. 4A-4E, rotation knob100is retained in substantially fixed longitudinal position relative to nose22due to the positioning of the first and second sets of proximal support walls130,140, respectively, between body portion21of housing20and distal base25of nose22and under the bias of retaining ring180and shell110. However, although rotation knob100is substantially fixed in longitudinal position relative to nose22due to the engagement of proximal end104of rotation knob100about neck23of nose22, rotation knob100is permitted to rotate about longitudinal axis “X-X” relative to housing20. The bias of retaining ring180and shell110towards their respective at-rest positions, which bias first and second sets of proximal support walls130,140, respectively, to approximate, or clamp about neck23of nose22also helps maintain the engagement of housing parts20a,20b, to one another, i.e., the clamping of rotation knob100about nose22inhibits substantial separation of housing parts20a,20bfrom one another.

In the engaged position, wherein rotation knob100is engaged about nose22, protrusions102of rotation knob100, which extend inwardly into hollow interior112of shell110, are biased into engagement within cut-outs19defined within shaft12to rotatably fix rotation knob100and shaft12to one another. Thus, upon rotation of rotation knob100relative to housing20, shaft12and end effector assembly90are similarly rotated relative to housing20. Further, the bias of retaining ring180to clamp proximal end104of rotation knob100about neck23of nose22may be sufficient to retain rotation knob100and, thus, end effector assembly90in fixed rotational orientation in the absence of manipulation of rotation knob100. Alternatively, neck23of nose22may includes a plurality of notches (not explicitly shown) defined therein that correspond to pre-determined intervals of rotation, e.g., 30 degrees, 60 degrees, 90 degrees, etc., of end effector assembly90. As such, rotation knob100may be incrementally rotated and locked in engagement with each successive notch (not shown) under the bias of retaining ring180and shell110to rotate and fix end effector assembly90in various different rotational positions.

Referring again toFIGS. 4A-4Eand5A-5C, in order to disengaged rotation knob100from nose22of housing20and shaft12, proximal end104of shell110of rotation knob100is flexed radially outwardly to the flexed position such that walls132,134of the first set of proximal support walls130are moved apart from one another and such that walls142,144of the second set of proximal support walls140are moved apart from one another to expand retaining ring180, thus permitting expansion of apertures136,146. Apertures136,146, are expanded sufficiently so as to permit passage of proximal end104of rotation knob100distally over distal base25of nose22of housing20to disengage rotation knob100from housing20. Further, upon outward flexing of shell110, protrusions102are withdrawn from cut-outs19defined within shaft12to disengage shaft12and rotation knob100from one another. Once rotation knob100has been disengaged from shaft12and nose22, rotation knob100may be slid distally along shaft12, ultimately passing over end effector assembly90to remove rotation knob100from forceps10.

Turning now toFIG. 6, another embodiment of a rotation knob200configured for use with forceps10is shown. Rotation knob200is similar to rotation knob100(FIGS. 4A-4E) and defines a generally conically-shaped configuration, although other configurations are also contemplated. Rotation knob200is monolithically formed as a single component and may be formed from any suitable material, e.g., biocompatible polymer(s), that provides at least some degree of flexibility to permit engagement of rotation knob100about nose22of housing20. Rotation knob200, except where specifically contradicted below, may include any of the features discussed above with respect to rotation knob100(FIGS. 4A-4E).

Continuing with reference toFIG. 6, rotation knob200includes a shell210defining the conically-shaped configuration of rotation knob200and having a generally hollow interior212, a distal wall220defining distal end202of rotation knob200, a plurality, e.g., four (4), spaced-apart, proximally-extending fingers230disposed at proximal end204of rotation knob200, and a lumen214extending longitudinally through shell210of rotation knob200. Shell210of rotation knob200includes a pair of opposed protrusions260extending inwardly into hollow interior212of shell210that are configured to engage opposed cut-outs19defined within shaft12to engage rotation knob200and shaft12to one another. Protrusions260extend into lumen214defined through rotation knob200and are longitudinally disposed between distal wall220and fingers230of rotation knob200.

Each finger230of rotation knob200includes an inwardly-extending tab240disposed at a free end244thereof. Tabs240of fingers230cooperate to define an aperture250through proximal end204of rotation knob200that, in conjunction with aperture250defined through distal wall220, define lumen214extending longitudinally through rotation knob200. Fingers230are formed at least partially from a resiliently flexible material, thus permitting fingers230to flex radially outwardly from an at-rest position to a flexed position, wherein the diameter of aperture250is expanded to permit passage of proximal end204of rotation knob200about distal base25of nose22of housing20. Fingers230are biased towards the at-rest position, wherein the diameter of aperture250generally approximates the diameter of shaft12, thus permitting passage of shaft12therethrough while fingers230of rotation knob200remain in a substantially at-rest, or un-flexed position.

In use, rotation knob200is first slid proximally over end effector assembly90with end effector assembly90passing through lumen214defined through shell210of rotation knob200. Upon reaching proximal end16of shaft12, with rotation knob200still disposed in the at-rest position, rotation knob200is inhibited from being translated further proximally due to the abutment of tabs240of fingers230of rotation knob200and distal base25of nose22of housing20. Thus, in order to permit passage of proximal end204of rotation knob200proximally beyond distal base25of nose22and into position about neck23of nose22, fingers230are flexed radially outwardly from the at-rest position to the flexed position, thereby increasing the diameter of aperture250and, thus, the proximal portion of lumen214so as to permit passage of distal base25of nose22therethrough.

Rotation knob200, in this flexed position, is now permitted to be advanced further proximally such that tabs240of fingers230are moved proximally over distal base25of nose22into position adjacent neck23of nose22. In this position, as shown inFIG. 5C, distal base25of nose22is disposed within hollow interior212of shell210longitudinally between distal wall220and fingers230. Upon achieving this position, with distal base25no longer disposed between fingers230, fingers230are resiliently biased back towards the at-rest position such that tabs240are approximated about neck23of nose22and aperture250is returned towards its at-rest diameter. In this position, with tabs240approximated, or clamped about neck23of nose22, rotation knob200is retained in substantially fixed longitudinal position relative to nose22due to the positioning of tabs240of fingers230between body portion21of housing20and distal base25of nose22under the bias of fingers230, although rotation knob200is permitted to rotate about longitudinal axis “X-X” relative to housing20. The clamping or bias of fingers230about neck23of nose22also helps maintain the engagement of housing parts20a,20bof housing20to one another, similarly as described about with respect to rotation knob100(seeFIGS. 4A-4E).

In the engaged position, wherein rotation knob200is engaged about nose22, protrusions260of rotation knob200are engaged within cut-outs19defined within shaft12to rotatably fix rotation knob200and shaft12to one another. Thus, upon rotation of rotation knob200relative to housing20, shaft12and end effector assembly90are similarly rotated relative to housing20.

In order to disengaged rotation knob200from nose22of housing20and shaft12, fingers230are flexed radially outwardly from the at-rest position back to the flexed position to expand aperture250such that tabs240of fingers230may pass distally over distal base25of nose22of housing20to disengage rotation knob200from housing20. Further, upon outward flexing of fingers230, protrusions260are withdrawn from cut-outs19defined within shaft12to disengage shaft12and rotation knob200from one another. Once rotation knob200has been disengaged from shaft12and nose22, rotation knob200may be slid distally along shaft12, ultimately passing over end effector assembly90to remove rotation knob200from forceps10.

With reference toFIG. 7, another embodiment of a rotation knob300configured to engage a distal end22′ of a housing20′ of a surgical instrument10′ is shown. Surgical instrument10′ may be a forceps, e.g., a forceps similar to forceps10(FIG. 1), or any other suitable surgical instrument including an end effector assembly disposed at a distal end of a shaft and a housing at the proximal end of the shaft for controlling operation of the end effector assembly. Rotation knob300is configured for use with a surgical instrument10′ including a housing20′ having a distal surface24′ which defines a distal opening26′ therethrough, rather than a distal nose configuration such as that described above with respect to forceps10(FIG. 1). Further, rather than having cut-outs defined within the shaft, surgical instrument10′ includes a bushing36′ engaged about shaft12′ towards proximal end16′ thereof that is configured to be received within a cavity312defined within rotation knob300to secure rotation knob300and shaft12′ to one another such that rotation knob300can be rotated to effect similar rotation of shaft12′ and the end effector assembly (not shown) thereof. Rotation knob300, except where specifically contradicted below, may include any of the features discussed above with respect to rotation knob100(FIGS. 4A-4E).

Continuing with reference toFIG. 7, rotation knob300includes a housing310defining a proximal end302, a distal end304, and a lumen306extending longitudinally therethrough. Lumen306is dimensioned to receive shaft12′ of surgical instrument10′ therethrough. More specifically, housing310includes a distal hub320disposed at distal end304thereof that defines an aperture322therethrough and a pair of opposed proximal walls330that cooperate to define an aperture332therethrough. Apertures322,332cooperate with one another to define lumen306extending longitudinally through housing310of rotation knob300. Housing310is at least partially formed from a resiliently flexible material that is transitionable between a first at-rest position and a first flexed position to permit proximal walls330to be flexed apart from one another, thereby increasing the diameter of aperture332and, thus, increasing the diameter of the proximal portion of lumen306. Housing310also defines an internal cavity312disposed about lumen306that, as mentioned above, is configured to retain bushing36′ of surgical instrument10′ therein.

A plurality of spaced-apart fingers340extends proximally from proximal end302of housing310. Each finger340includes an outwardly-extending flange344disposed at the free end342thereof. As a result of this configuration, a slot350is defined between flanges344of fingers340and proximal end302of housing310. Fingers340are formed at least partially from a resiliently flexible material such that fingers340may be flexed radially-inwardly from a second at-rest position, wherein fingers340cooperate to define a first outer peripheral diameter, to a second flexed position, wherein fingers340converge towards one another to define a reduced outer peripheral diameter. Rotation knob300, including fingers340, may be monolithically formed as a single component.

In use, rotation knob300is first slid over the end effector assembly (not shown) of the surgical instrument10′ and proximally along shaft12′. Upon reaching bushing36′, proximal end302of rotation knob300is flexed radially-outwardly from its at-rest position (e.g., the first at-rest position) to its flexed position (e.g., the first flexed position) to permit passage of bushing36′ through lumen306and into cavity312defined within housing310. Bushing36′ is configured to be engaged within housing310via friction-fitting (under the resilient bias of housing310back to its at-rest position), or other suitable engagement, to engage shaft12′ and rotation knob300to one another such that rotation of rotation knob300relative to longitudinal axis “X-X” effects corresponding rotation of shaft12′ and the end effector assembly (not shown) about longitudinal axis “X-X.” Once bushing36′ is positioned within cavity312, housing310may be released to return under bias (or otherwise return) back towards the at-rest position to engage bushing36′ within cavity312of housing310.

With housing310disposed about bushing36′ of shaft12′, rotation knob300may then be engaged to distal end22′ of housing20′. In order to engage rotation knob300to distal end22′ of housing20′, fingers340are flexed inwardly from their at-rest position (e.g., the second at-rest position) to their flexed position (e.g., the second flexed position) to define a reduced outer peripheral diameter that is sufficiently small so as to permit passage of fingers340through distal opening26′ formed in distal surface24′ of housing310. Upon passing through opening26′, fingers340are permitted to resiliently return back towards their at-rest position, thus engaging distal surface24′ of housing20′ within slot350defined between flanges344of fingers340and proximal end304of housing310. In this engaged position, rotation knob300is substantially fixed in longitudinally position relative to housing20′, but is permitted to rotate about longitudinal axis “X-X” relative to housing20′.

Disengagement of rotation knob300from housing20′ and shaft12′ is effected in the opposite manner as the engagement described above, namely, fingers340are flexed inwardly to the second flexed position wherein fingers340define a reduced outer peripheral diameter, thus permitting withdrawal of fingers340through distal opening26′ formed in distal surface24′ of housing20′. Fingers340are then returned under bias back towards the second at-rest position. Thereafter, housing310of rotation knob300is flexed outwardly to the first flexed position to permit bushing36′ to be translated proximally through the expanded proximal portion of lumen306to remove bushing36′ from cavity312of rotation knob300. Once bushing36′ has been removed from rotation knob300, housing310is permitted to return under bias back towards the first at-rest position. Ultimately, rotation knob300is slid distally along shaft12′ and passed over the end effector assembly (not shown) thereof to remove rotation knob300from surgical instrument10′.

Referring now toFIGS. 8A-8C, various configurations of rotation knobs, e.g., rotation knobs400,500,600, are shown. Rotation knobs400,500,600may be configured for use with forceps10(FIG. 1), surgical instrument10′ (FIG. 7), or any other suitable surgical instrument, similarly as described above with respect to rotation knobs100,200,300(FIGS. 5A-5C,6,7, respectively). Additionally, the ergonomic features of these rotation knobs, or any other suitable ergonomic features, may be incorporated into the rotation knobs described herein. In other words, although specific ergonomic features of rotation knobs100-600are shown and described herein, rotation knobs100-600may be provided in any suitable size, shape, and/or ergonomic configuration.

Further, it is envisioned that these various different rotation knobs be interchangeable with one another, thus allowing the user to select a desired rotation knob depending on the surgical procedure to be performed, the surgeon's preference, or other factors. This interchangeability is facilitated in that the rotation knobs described herein are easily and efficiently engaged and disengaged from a surgical instrument, e.g., forceps10(FIG. 1), thus allowing for easy and efficient interchanging of rotation knobs. This configuration provides increased customization and versatility to a surgical instrument, without requiring a separate instrument that is customized for each user and/or procedure. Such a configuration also permits the rotation knobs to be used as disposable components that can be easily engaged and disengaged from the reusable components of a particular surgical instrument, thus facilitating removal of the first, used rotation knob, sterilization of the reusable components, and reassembly of the instrument with a second, new rotation knob in preparation for reuse.

With reference toFIG. 8A, rotation knob400includes a generally-cylindrical body410having a plurality of flanges420extending radially outwardly therefrom substantially along the length of body410. Flanges420taper distally to proximally and are spaced-apart from one another to define a plurality of finger recesses430therebetween that facilitate grasping and rotation of rotation knob400. Rotation knob400may otherwise be configured similarly to any of the rotation knobs described above.

Referring toFIG. 8B, rotation knob500includes a pair of spaced-apart housing members510,520interconnected by a tube segment530. Housing members510,520each define a generally annular configuration having a plurality of flanges512,522, respectively, extending radially outwardly therefrom. Flanges512are spaced-apart from one another, as are flanges522, to define a plurality of finger recesses514,524, respectively, therebetween. Finger recesses514,524facilitate the grasping and rotation of rotation knob500. Rotation knob500may otherwise be configured similarly to any of the rotation knobs described above.

As shown inFIG. 8C, rotation knob600defines a more spherical-shaped body610and includes a plurality of finger-tip-shaped recesses620defined therein for grasping and rotating rotation knob600. Rotation knob600may otherwise be configured similarly to any of the rotation knobs described above.