Apparatus and method for treating disorders of the ear, nose and throat

Apparatus for use in surgeries to treat disorders of the ear, nose, and throat including a hand-held device and rotating blade assembly. The apparatus may be connected to a vacuum source. A method of use is also disclosed.

TECHNICAL FIELD

The present disclosure relates generally to surgical instruments and methods and, more particularly, to surgical instruments for use in surgeries to treat disorders of the ear, nose, and throat.

BACKGROUND

Functional endoscopic sinus surgery (FESS) is a common type of surgery used to treat chronic sinusitis, as well as remove tumors, polyps and other aberrant growths from the nose. In a typical FESS procedure, an endoscope is inserted into the nostril along with one or more surgical instruments. The endoscope typically provides the surgeon with a direct line-of-sight view to permit the surgeon to visualize a number of relevant anatomical structures within the surgical field. Under visualization through the endoscope, the surgeon may remove diseased or hypertrophic tissue or bone and/or enlarge the ostia of the sinuses to restore normal drainage of the sinuses. A number of surgical instruments may be used to cut and remove tissue and/or bone, cauterize, suction, etc. during a FESS procedure.

Nasal polyp surgery is one type of FESS procedure that is typically performed in an operating room with the patient under general anesthesia. It typically involves a powered fixed piece of capital equipment that includes a console and a hand piece. This equipment usually requires electrical, vacuum, and saline hookups. This surgical method is highly invasive and requires substantial recovery time for the patient

Nasal polyps can also be removed in the physician's office with simple tools such as forceps. The patient is typically awake during the procedure. The physician is limited by what he can comfortably reach and remove without creating too much discomfort to the patient. This procedure is relatively limited in the ability to remove substantial nasal polyps.

Another removal tool is a microdebrider, which is a rotary cutting tool that may be used to shave tissue and/or bone. Microdebriders may be connected to a vacuum source, which may be used to create suction that remove excess blood and tissue from the surgical field.

SUMMARY

According to one aspect of the disclosure, a surgical instrument and method for performing an ear, nose, and throat surgery is disclosed. The surgical instrument includes a hand piece and an outer shaft coupled to the hand piece that extends to a distal end. The outer shaft has a rounded, convex distal surface and a first plurality of cutting teeth defined at the distal end. The instrument also includes an inner shaft positioned in the outer shaft. The inner shaft has a passageway and a second plurality of cutting teeth. The surgical instrument includes a cutting slot that is partially defined by the first plurality of cutting teeth, and the inner shaft is configured to rotate relative to the outer shaft such that the first plurality of cutting teeth and the second plurality of cutting teeth cooperate to cut tissue advanced into the passageway through the cutting slot.

In some embodiments, the outer shaft may include a cylindrical outer surface that extends along a longitudinal axis of the outer shaft to the rounded, convex distal surface, and the cutting slot may be defined in the cylindrical outer surface. In some embodiments, the second plurality of cutting teeth may be axially aligned with the cutting slot.

Additionally, in some embodiments, the rounded, convex distal surface may extend from a distal apex to a proximal edge, and the proximal edge of the convex distal surface may define a distal end of the cutting slot. The proximal edge of the rounded, convex distal surface may be one of a chamfered edge and a rounded edge.

In some embodiments, the cutting slot may extend to a proximal end defined by a distal edge of an outer surface of the outer shaft, the proximal edge of the convex distal surface and the distal edge of the outer surface of the outer shaft may cooperate to define a curved imaginary plane, and the first plurality of cutting teeth may be recessed below the curved imaginary plane.

In some embodiments, the distal edge of the outer surface may be one of a chamfered edge and a rounded edge. In some embodiments, each cutting tooth of the first plurality of cutting teeth may include a planar outer surface.

Additionally, in some embodiments, the hand piece may include a connector configured to be coupled to a negative pressure source to fluidly connect the passageway of the inner shaft to the negative pressure source.

In some embodiments, the surgical instrument may also include a drive mechanism configured to rotate the inner shaft relative to the outer shaft. In some embodiments, the drive mechanism may include an electric motor positioned in the hand piece. In some embodiments, the drive mechanism may include a cable drive mechanism configured to be coupled to the hand piece.

In some embodiments, the outer shaft and the inner shaft may be removably coupled to the hand piece. Additionally, in some embodiments, the instrument may further include a hub coupled to the outer shaft. The hub may include a plurality of splines engaged with the hand piece to secure the outer shaft to the hand piece. In some embodiments, the instrument may include a second hub coupled to the inner shaft. The second hub may include a second plurality of splines engaged with the hand piece to pivotally couple the inner shaft to the hand piece.

According to another aspect, a surgical instrument includes a hand piece, a first shaft coupled to the hand piece, and a second shaft positioned in the first shaft. The first shaft includes a cylindrical outer surface extending along a longitudinal axis of the first shaft to an atraumatic tip, a closed distal end, and a cutting slot defined in the cylindrical outer surface adjacent to the closed distal end. The second shaft has a plurality of cutting teeth axially aligned with the cutting slot, and the second shaft is configured to rotate relative to the first shaft such that the plurality of teeth cut tissue in the cutting slot.

In some embodiments, the closed distal end of the first shaft may define a spherical tip. Additionally, in some embodiments, the second shaft may include a spherical distal tip.

In some embodiments, the first shaft may be formed from a first material and the second shaft is formed from a second material different from the first material. In some embodiments, a distal section of the first shaft may be malleable.

In some embodiments, the distal section of the first shaft may include a plurality of slots defined in the first shaft. In some embodiments, a proximal section of the first shaft may be substantially rigid.

In some embodiments, a distal section of the second shaft may be flexible. In some embodiments, a proximal section of the second shaft may be substantially rigid.

According to another aspect, a surgical cutting tool is disclosed. The surgical cutting tool comprises a first shaft including a cylindrical outer surface extending along a longitudinal axis of the first shaft, a first passageway extending along the longitudinal axis from an open proximal end to a closed distal end, and a cutting slot extending inward from the cylindrical outer surface to the first passageway. The cutting slot is positioned adjacent to the closed distal end. The surgical cutting tool also includes a second shaft positioned in the first passageway of the first shaft. The second shaft has a second passageway and a cutting edge that is axially aligned with the cutting slot. The second shaft is configured to rotate relative to the first shaft such that the cutting edge cuts tissue advanced into the second passageway through the cutting slot.

In some embodiments, the cutting slot may be partially defined by a plurality of cutting teeth, and the cutting edge and the plurality of cutting teeth may cooperate to cut tissue advanced into the second passageway through the cutting slot when the second shaft is rotated. In some embodiments, the plurality of cutting teeth may be a first plurality of cutting teeth, and the cutting edge includes a second plurality of cutting teeth.

Additionally, in some embodiments, the plurality of cutting teeth may be recessed from the cylindrical outer surface. In some embodiments, the first shaft may include a distal section that defines a first diameter and a proximal section that defines a second diameter greater than the first diameter.

DETAILED DESCRIPTION OF THE DRAWINGS

Referring now toFIG. 1, a surgical instrument10for use in surgeries to treat disorders of the ear, nose, and throat including, for example, nasal polyp surgery is shown. The instrument10includes a hand piece12and a blade assembly14configured to be coupled to the hand piece12. The blade assembly14includes a cutting slot16that is positioned at its distal end18.

When the instrument10is used to remove diseased or damaged tissue from a patient, the distal end18of the blade assembly14may be advanced into a nasal passage. The instrument10may be operated to position the target tissue within the cutting slot16and shave or cut the target tissue. Suction may then be used to remove the severed tissue, as described in greater detail below.

The hand piece12of the surgical instrument10includes an elongated body22and a grip24formed on the body22. The grip24is configured to be grasped by a user during operation of the surgical instrument10. In other embodiments, the hand piece may include a handle or may include one or more ergonomic features to facilitate use of the instrument10. The elongated body22and the grip24may be formed from the same material such as, for example, a plastic, rigid polymer, or other rigid materials suitable for autoclaving. The grip24may also be formed from a soft or padded material such as neoprene. In some embodiments, the hand piece12may be wholly or partially covered by a disposable outer skin or wrap during surgery such that the hand piece12does require re-sterilization or autoclaving between surgeries. In other embodiments, the hand piece12may be configured to be disposable after a single-use.

The hand piece12includes an aperture30defined in a longitudinal end32of the elongated body22. As shown inFIG. 1, the aperture30is sized to receive a proximal end34of the blade assembly14. The hand piece12also includes a connector36and a connector cable38positioned at the opposite longitudinal end40of the body22. The connector36and the cable38are configured to be coupled with corresponding connectors42,44of a negative pressure source and an electrical cable52, respectively.

The connector42extends from a hose46that is connected to a source of negative pressure such as, for example, vacuum pump48. The connector36of the hand piece12is configured to engage the hose connector42such that the hand piece12(and hence the blade assembly14) may be connected to the vacuum pump48. It should be appreciated that in other embodiments the negative pressure source may take the form of an air compressor, or other suction device.

In the illustrative embodiment, the electrical cable52includes the connector44, which is coupled to a power source50such as, for example, a standard domestic power outlet. The power source50is configured to supply electrical power to the hand piece12. The cable38of the hand piece12includes a connector (not shown) that is configured to engage the connector44. In that way, electrical power may be supplied from the source50to the electrically-operated components (seeFIG. 2) of the hand piece12.

As shown inFIG. 1, the hand piece12also includes a control panel60positioned on the elongated body22. In the illustrative embodiment, the control panel60includes a single control button62, which may be toggled to operate the surgical instrument10. In other embodiments, the hand piece12may include additional controls such as toggles, levers, or other buttons to individually activate the electrically-operated components of the instrument10and/or the vacuum pump48. It should also be appreciated that in other embodiments the control panel60may be omitted from the hand piece12, and the instrument10and/or the vacuum pump48may be activated using a foot pedal or other control device.

In still other embodiments, the negative pressure source may be integrated into a portable console. Similarly, the power source may be included in a surgical console. The hand piece12may be configured to be plugged into a wall electrical socket via a plug or adaptor. The hand piece12may also be configured to be battery-powered.

Referring now toFIG. 2, the hand piece12includes an electric motor66that is positioned in an inner chamber68of the elongated body22. In the illustrative embodiment, the motor66is an electric motor powered by direct current (DC). In other embodiments, the motor66may be powered by alternating current (AC). An electrical contact switch70is positioned in the chamber68below the button62. When the button62is toggled or pressed by the user, the switch70is configured to generate an electrical output. The electrical output is relayed to the pump48and the power source50via the cable52, thereby activating the pump48and energizing the motor66.

As described above, the hand piece12is configured to receive the blade assembly14. In the illustrative embodiment, the hand piece12of the surgical instrument10includes a mounting collar72, which receives the proximal end34of the blade assembly14. As shown inFIGS. 1-2, the mounting collar72is positioned in the aperture30of the hand piece12. The mounting collar72illustratively includes a splined surface74that defines a passageway78. When the proximal end34of the blade assembly14is seated in the aperture30, the blade assembly14extends through the passageway78and a set of splines76defined on the blade assembly14engage the splined surface74. In that way, the blade assembly14is secured to the hand piece12. In other embodiments, the mounting collar72and the blade assembly14might include corresponding threads to secure the assembly14to the hand piece12. In still other embodiments, a combination of pins, slots, or other fastening devices may be used to secure the assembly14to the hand piece12. It should also be appreciated that in other embodiments part (or all) of the blade assembly may be permanently fixed to the hand piece.

While the mounting collar72is fixed in position relative to the elongated body22, the hand piece12also includes an inner collar80that is pivotally coupled to the body22. In the illustrative embodiment, the collar80is mounted within the chamber68of the body22on bearings (not shown), which permit the inner collar80to rotate within the body22. The inner collar80, like the collar72, includes a splined surface82that defines a passageway84. When the proximal end34of the blade assembly14is seated in the aperture30, the proximal tip86of the blade assembly14is positioned in the passageway84and a set of splines88defined on the blade assembly14engage the splined surface82of the collar80.

A gear assembly90is positioned between the motor66and the inner collar80to transmit the output of the motor66to the collar80(and hence the spline88of the blade assembly14). In the illustrative embodiment, the gear assembly90is coupled to an output shaft92of the motor. The gear assembly90includes a plurality of teeth (not shown), which are configured to engage a corresponding set of teeth (not shown) defined on the outer surface94of the inner collar80. The gear assembly90may include one or more gears such as, for example, helical, bevel, worm, or other devices configured to transmit the output of the motor to the collar80.

When the motor66is energized, the motor66causes the output shaft92to rotate. The rotation of the shaft92is transmitted to the collar80via the gear assembly90, thereby causing the inner collar80to rotate. As described in greater detail below, the rotation of the collar80causes an inner blade shaft100of the blade assembly14to rotate when the blade assembly14is secured to the hand piece12.

The hand piece12also includes a passageway96that is positioned between the connector36and the inner collar80. The passageway96fluidly couples the passageway84of the inner collar80to the connector36. In that way, the passageway84may be exposed to negative pressure when the vacuum pump48is activated.

As described above, the surgical instrument10includes a blade assembly14, which is the cutting tool of the surgical instrument10. Referring now toFIGS. 3-5, the blade assembly14includes the inner blade shaft100, which is positioned within an outer blade shaft102. As described above, the blade assembly14includes a cutting slot16into which tissue may be placed to be shaved or cut. As shown inFIG. 3, the cutting slot16is defined in the outer blade shaft102, and the inner blade shaft100includes a longitudinal passageway104that opens into the cutting slot16.

The inner blade shaft100also includes cutting edges106,108that are axially aligned with the cutting slot16. The edges106,108are configured to cut or shaft tissue placed in the cutting slot16. As described in greater detail below, when the inner blade shaft100is rotated about its longitudinal axis110, tissue advanced into the cutting slot16may be sliced by the cutting edge106or the cutting edge108. In the illustrative embodiment, the outer blade shaft102also includes a pair of cutting edges112,114, which cooperate with the cutting edges106,108of the inner blade shaft100to slice the tissue. The severed tissue may then be drawn into the longitudinal passageway104of the inner blade shaft100by suction.

As shown inFIG. 4, the blade shafts100,102are attached to an inner hub120and an outer hub122, respectively. In the illustrative embodiment, the hubs120,122are each formed from rigid material such as, for example, a metallic material, plastic, or rigid polymer. The inner hub120is positioned at the proximal end34of the blade assembly14and includes a cylindrical outer surface124that extends from an end126positioned adjacent to the outer hub122to an end128. The plurality of splines88are positioned at the end126and extend outwardly from the surface124. As described above, the splines88are configured to engage the splined surface82of the inner collar80of the hand piece12when the blade assembly14is secured thereto. In that way, the inner hub120may be rotated with the collar80when the motor66is energized.

The inner hub120also has an annular groove130that is defined in the cylindrical outer surface124at the end128. A seal such as, for example, an elastomeric o-ring132is positioned in the groove130. When the blade assembly14is positioned in the aperture30of the hand piece12, the o-ring132engages a portion of the surface82of the inner collar80to create an air-tight barrier. It should be appreciated that in other embodiments the seal may be omitted from the blade assembly14, and the hand piece12may include an o-ring or other seal that engages the inner hub.

As shown inFIG. 5, a longitudinal bore134extends through the inner hub120. The bore134is sized to receive a proximal section136of the inner blade shaft100. In the illustrative embodiment, the inner blade shaft100is press-fit into the bore134. In other embodiments, a combination of splines, slots, pins, welding, swaging, or other fasteners may be used to secure the hub120to the shaft100. It should be appreciated that the hub120and/or the shaft100may configured for disassembly and reuse. In other embodiments, the hub120may be permanently fixed to the shaft100. As shown inFIGS. 4-5, the inner blade shaft100extends outwardly from the inner hub120to define the proximal tip86of the blade assembly14.

The outer hub122of the blade assembly14is positioned distal of the inner hub120. As shown inFIG. 4, the hub122includes a cylindrical outer surface144that extends from an end146positioned adjacent to the inner hub120to an end148. The plurality of splines76extend outwardly from the surface144. As described above, the splines76are configured to engage the splined surface74of the mounting collar72of the hand piece12when the blade assembly14is secured thereto. In that way, the outer hub122is fixed relative to the hand piece12and hence does not rotate with the inner hub120.

The outer hub122also has an annular groove150that is defined in the cylindrical outer surface144adjacent to the end146. The groove150is configured to receive a seal such as, for example, an elastomeric o-ring. that is secured to the mounting collar72. In the illustrative embodiment, the hand piece12includes an elastomeric o-ring (not shown), which is positioned in the groove150when the blade assembly14is positioned in the aperture30of the hand piece12. It should be appreciated that in other embodiments the seal may be attached to the outer hub122.

As shown inFIG. 5, a longitudinal bore154extends through the outer hub122. The bore154is sized to receive a proximal section156of the outer blade shaft102. In the illustrative embodiment, the outer blade shaft102is press-fit into the bore154. In other embodiments, a combination of splines, slots, pins, welding, swaging, and other fasteners may be used to secure the hub122to the shaft102. It should be appreciated that the hub122and/or the shaft102may configured for disassembly and reuse. In other embodiments, the hub122may be permanently fixed to the shaft102.

The longitudinal bore154of the outer hub122is defined by a cylindrical inner surface158. The outer hub122also has an annular groove160that is defined in the surface158at the end148. A seal such as, for example, an elastomeric o-ring162is positioned in the groove160. As shown inFIG. 5, the o-ring162engages the proximal section136of the inner blade shaft100. In the illustrative embodiment, the seal162facilitates the positioning of the inner blade shaft100within the outer blade shaft102. It should be appreciated that in other embodiments the seal may be omitted. In other embodiments, the blade assembly14may include a bearing or other device that aligns the inner blade shaft100with the outer blade shaft102.

The blade assembly14has a length defined between the distal end18and the proximal tip86. In the illustrative embodiment, the length of the blade assembly is between about 11 centimeters and about 12 centimeters. It should be appreciated the blade assembly14may be longer or shorter depending on the nature of the surgery and the anatomy of a particular patient.

Referring now toFIG. 6, the inner blade shaft100has an elongated tube170that extends from a distal end172to a proximal end174. The tube170includes a cylindrical proximal section136and a distal section176. The distal section176includes a cylindrical outer surface178, which has an outer diameter that is larger than the outer diameter of the proximal section136. In the illustrative embodiment, the distal section176is stepped relative to the proximal section136. In other embodiments, the tube170may include multiple step sections or taper along its length. In still other embodiments, the outer diameter of the proximal section may be larger than the outer diameter of the distal section to, for example, facilitate suction and reduce the possibility of clogging in certain applications.

In the illustrative embodiment, the proximal section136of the elongated tube170is formed from a bio-compatible metallic material such as, for example, stainless steel, and the distal section176is formed from a bio-compatible surgical steel such as, for example a high carbon steel or nickel alloy that is welded, press fit, or swaged to the proximal section136. In that way, the distal section176is formed as a hardened steel tip of the tube170. In other embodiments, the tube170may be formed from a plastic or other rigid polymer.

Additionally, the sections136,138of the shaft100may formed separately from the same metallic material and later assembled by welding, press fit, or swaging. In other embodiments, the sections136,138may be formed as a single, monolithic component or the shaft100may be formed from additional pieces that are later assembled. Additionally, the sections136,138may be formed from different materials. For example, the distal section138may be formed from a flexible or semi-flexible material such as a flextube, and the proximal section136may be formed from a rigid or semi-rigid material.

As shown inFIG. 6, the elongated tube170defines the longitudinal axis110of the inner blade shaft100. In the illustrative embodiment, the elongated tube170is substantially straight. In other embodiments, the elongated tube170may define a curve or arc. In still other embodiments, one part of the tube170may be substantially straight and another part may define a curve or arc. For example, the part of the tube170may define an arc of approximately 60 degrees.

As described above, the inner blade shaft100includes a pair of cutting edges106,108, which are positioned in the distal section176of the tube170. In the illustrative embodiment, the cutting edges106,108are formed from the same metallic material as the rest of distal section176. In other embodiments, the cutting edges106,108may be formed from one material such as, for example, a stainless steel, and the rest of the distal section176(and elongated tube170) may be formed from another material such as, for example, a polymeric material. The cylindrical outer surface178has a distal edge180that connects the proximal ends of the edges106,108, and the elongated tube170includes another edge182that connects the distal ends of the edges106,108. The edges106,108,180,182cooperate to define a distal opening184in the elongated tube170. The distal opening184is axially aligned with the cutting slot16when the blade shafts100,102are assembled.

As shown inFIGS. 5-6, the distal opening184opens into the longitudinal passageway104of the inner blade shaft100. The passageway104is defined by a cylindrical inner surface186and extends proximally to an opening188defined in the proximal end174of the elongated tube170. The wall thickness defined between the inner surface186and the outer surface178is between about 0.100 and 0.130 millimeters and is sized to permit a larger diameter passageway104.

The passageway104has a diameter190that is defined by the inner surface186. The diameter190is in a range of about 1.8 millimeters to about 2.9 millimeters. In the illustrative embodiment, the diameter190is constant along the length of the passageway104, but, in other embodiments, the diameter190may vary. For example, the diameter of the passageway in the distal section176of the tube170may be less than the diameter of the passageway in the proximal section136. In that way, the diameter may be, for example, stepped or tapered along the length of the tube170to facilitate suction and reduce the possibility of clogging in certain applications. Additionally, in the illustrative embodiment, the inner surface186of the tube170is coated with a lubricious material such as, for example, a hydrophilic material, silicone, and so forth to reduce the possibility of clogging.

The outer blade shaft102of the blade assembly14includes an elongated tube200that extends from a distal end202to a proximal end204. In the illustrative embodiment, the elongated tube200is formed from a bio-compatible metallic material such as, for example, stainless steel. The distal end202of the tube200is formed from a surgical steel such as, for example a high carbon steel or nickel alloy that is welded, press fit, or swaged to the proximal section of the tube200. In that way, the distal end202is formed as a hardened steel tip of the tube170. In the illustrative embodiment, the distal end202of the outer shaft102and the distal section176of the inner shaft are formed from different materials. It should be appreciated that in other embodiments the shafts100,102may be formed from the same material.

In other embodiments, the tube200may be formed from a plastic or other rigid polymer. While the elongated tube200is illustratively formed separately in one or more pieces and later assembled, in other embodiments the tube200may be formed as a single, monolithic component and from the same material. In other embodiments, each of the pieces of the tube200may be formed from different materials or modified to possess different properties. For example, one section of the tube200may be made malleable or bendable while another section of the tube200remains rigid or semi-rigid. In that way, the malleable portion of the tube may be bent during surgery to provide the surgeon with improved access to the surgical area and returned to its original shape after surgery.

As shown inFIG. 6, the elongated tube200defines the longitudinal axis206of the outer blade shaft102. In the illustrative embodiment, the elongated tube200is substantially straight. In other embodiments, the elongated tube200may define a curve or arc. In still other embodiments, one part of the tube200may be substantially straight and another part may define a curve or arc.

In the illustrative embodiment, the tube200has a constant outer diameter. In other embodiments, the tube200may include one or more stepped sections along its length. In still other embodiments, the tube200may taper along its length. In still other embodiments, the outer diameter of the proximal section may be smaller than the outer diameter of the distal section to, for example, accommodate a similarly configured inner blade shaft. In other embodiments, the distal section of the shaft102may have an outer diameter smaller than the outer diameter of proximal section to facilitate visualization of the surgical site.

The elongated tube200includes a cylindrical outer surface208that extends between the ends202,204. In the illustrative embodiment, the outer surface208is coated with a lubricious material such as, for example, a hydrophilic material, silicone, and so forth to reduce friction and facilitate movement of the shaft102within the nasal passage. In other embodiments, the tube200may also be coated with an anti-reflective material.

As described above, the outer blade shaft102includes the cutting slot16, which is defined at the distal end202in the surface208. The shaft102also has a pair of cutting edges112,114that line the slot16. In the illustrative embodiment, the cutting edges112,114are formed from the same metallic material as the rest of distal end202of the tube200. In other embodiments, the cutting edges112,114may be formed from one material such as, for example, a stainless steel, and the rest of the distal end202(and elongated tube200) may be formed from another material such as, for example, a polymeric material.

As shown inFIG. 6, the cylindrical outer surface208has a distal edge210that connects the proximal ends of the edges112,114. The elongated tube200also includes another edge212that connects the distal ends of the edges112,114. In the illustrative embodiment, the edges112,114,210,212cooperate to define the cutting slot16in the elongated tube200.

As shown inFIGS. 5-6, the cutting slot16opens into a longitudinal passageway214of the outer blade shaft102. The passageway214is defined by a cylindrical inner surface216and extends proximally to an opening218defined in the proximal end204of the elongated tube200. The wall thickness defined between the inner surface and the outer surface of the shaft102is sized to permit a larger diameter passageway and thereby a larger diameter inner blade shaft.

The passageway214has a distal diameter220that is defined by the inner surface216. The diameter220is illustratively in a range of about 2.4 millimeters to about 3.5 millimeters. The passageway214has a proximal diameter222that is greater than the distal diameter220. The diameter222is in a range of about 2.7 millimeters to about 3.8 millimeters. It should be appreciated that in other embodiments, the passageway214may have a constant diameter along its length.

As shown inFIG. 5, the inner blade shaft100is inserted into the passageway214of the outer blade shaft102when the blade assembly14is assembled. In the illustrative embodiment, the distal section176of the inner blade shaft100has a maximum outer diameter that substantially matches the inner distal diameter220of the outer blade shaft102. The proximal section136of the inner blade shaft100has a maximum outer diameter that is less than the inner proximal diameter222of the outer blade shaft102. In that way, a gap224is defined between proximal sections of the blade shafts100,102, while the matching diameters of the distal sections, in conjunction with the o-ring162at the distal end202of the outer shaft102, center the inner blade shaft100in the passageway214such that longitudinal axes110,206are co-linear.

As shown inFIG. 6, the outer surface208of the blade shaft102has an outer diameter226. The diameter226is in a range of about 3.0 millimeters to about 4.0 millimeters. In the illustrative embodiment, the diameter226is constant along the length of the blade shaft102, but, in other embodiments, the diameter226may vary. For example, the outer diameter of the blade shaft102at its distal end202may be less than its outer diameter at the proximal end204. In that way, the diameter may be, for example, stepped or tapered along the length of the shaft.

Referring now toFIGS. 7-8, the outer blade shaft102includes a closed distal tip228. In other words, the longitudinal passageway214is not exposed or accessible through the tip228of the blade shaft102and access is permitted at the distal end202only through the cutting slot16in the surface208. In that way, the distal tip228is an atraumatic tip that prevents or reduces damage to the anatomy caused by the distal end18of the blade assembly14. In the illustrative embodiment, the distal tip228is defined by a rounded, convex surface230such that the tip228is bull-nosed. In the illustrative embodiment, the surface230is a spherical, but it should be appreciated that in other embodiments the surface230may take a rounded form other than spherical.

The rounded, convex surface230extends from an apex232to a proximal edge212. As described above, the edge212cooperates with the edges112,114,210to define the cutting slot16. As shown inFIGS. 7-8, each of the edges112,114,210,212includes a chamfer or radius. The edge210and the edge212cooperate to define a curved imaginary plane234that defines the outer boundary of the cutting edges112,114. In that way, the edges112,114are recessed and the blade shaft102has no sharp edges that extend beyond the outer surfaces208,230.

Each of the cutting edges112,114of the shaft102is illustratively serrated, and each edge includes a pair of cutting teeth236. In other embodiments, one or both of the cutting edges112,114may include additional cutting teeth. In still other embodiments, one or both of the edges112,114may include a single, continuous sharp edge. As shown inFIGS. 7-8, each tooth236extends from a base238to a tip240positioned within the boundary defined by the curved imaginary plane234. Each tooth236is illustratively angled approximately 50 degrees relative to horizontal.

Each tooth236also includes a substantially planar outer surface242extending between the tip240and the base238. As shown inFIG. 7, the teeth236are equal in length. In other embodiments, the one or more teeth may extend different lengths. Each tooth236also includes a concave curved inner surface244(seeFIGS. 12-13) that substantially matches the cylindrical inner surface216of the outer blade shaft102.

As shown inFIG. 7, the cylindrical inner surface216is connected to a rounded, concave inner surface246, which defines a chamber248at the distal end of the longitudinal passageway214. In the illustrative embodiment, the inner surface246has a shape that corresponds to the shape of the outer rounded, convex surface230that defines the distal tip228. In other embodiments, the distal end of the passageway214may be defined by a flat planar surface extending inward from the cutting slot16.

Referring now toFIGS. 9-10, the inner blade shaft100includes a closed distal tip260that is received in the chamber248defined in the outer blade shaft102. In the illustrative embodiment, the distal tip260is defined by a rounded, convex surface262that matches the shape and configuration of the rounded, concave inner surface246of the outer blade shaft102. In the illustrative embodiment, the surface262is a spherical, but it should be appreciated that in other embodiments the surface262may take a rounded form other than spherical.

The rounded, convex surface262extends from an apex264to a proximal edge182. As described above, the edge182cooperates with the edges106,108,180to define the distal opening184of the inner blade shaft100. In the illustrative embodiment, the area of the distal opening is approximately two-thirds of the cross-sectional area of the longitudinal passageway104.

Each of the cutting edges106,108of the shaft100is illustratively serrated, and each edge includes a number of cutting teeth266. In other embodiments, one or both of the cutting edges106,108may include additional cutting teeth. In still other embodiments, one or both of the edges106,108may include a single, continuous sharp edge. As shown inFIGS. 9-10, each tooth266extends from a base268to a tip270.

Each tooth266also includes a curved outer surface272extending between the tip240and the base238. The outer surfaces272substantially match inner surfaces244of the teeth236of the outer blade shaft102. As shown inFIG. 9, the teeth266are equal in length. In other embodiments, the one or more teeth may extend different lengths. Each tooth266also includes a substantially planar inner surface274(seeFIGS. 12-13).

As described above in regard toFIG. 3, the cutting edges106,108of the inner blade shaft100cooperate with the cutting edges112,114to cut the tissue of a patient. In the illustrative embodiment, the cutting teeth266of the inner blade shaft100are offset from the cutting teeth236of the outer blade shaft102, as shown inFIG. 3. In that way, the teeth236,266form a common cutting edge on each side of the slot16when the inner blade shaft100is rotated relative to the outer blade shaft102.

Referring now toFIG. 11, a blade assembly14may be attached to hand piece12in preparation for surgery. To do so, the proximal end34of the blade assembly14is aligned with the aperture30defined in the distal end32of the hand piece12. The blade assembly14is then advanced into the aperture30. As the blade assembly14is moved along the aperture30, the inner hub120is moved through the passageway78defined in the mounting collar72. The blade assembly14may be rotated to align the splines88of the inner hub120with the slots defined in the splined surface82of the inner collar80.

The blade assembly14may be advanced further into the aperture30to engage the splines88with the splined surface82, thereby connecting the inner collar80with the hub120. As the blade assembly14is advanced further into the aperture30, the splines76of the outer hub122engage the splined surface74of the mounting collar72, thereby fixing the outer hub122(and hence the outer blade shaft102) in position relative to the hand piece12. When the blade assembly14is properly positioned, the o-ring132attached to the inner hub120is engaged with the splined surface82, and the proximal opening188of the inner blade shaft100is fluidly connected with the passageway84of the collar80and the passageway96.

Prior to performing the surgery, the connector cable38of the hand piece12may be coupled to the connector44of the electrical cable52to supply electrical power to the motor66. Additionally, the connector36of the hand piece12may be coupled to the connector42, thereby connecting the vacuum pump48to the hand piece12.

In a nasal polyp surgery, an endoscope may be advanced into the nasal passage of a patient to provide a view of the surgical area. The distal end18of the blade assembly14may be advanced into the nasal passage with the endoscope. In the illustrative embodiment, the closed distal tip228and the recessed cutting edges112,114reduce the possibility of inadvertently nicking or cutting tissue or bone during insertion of the device.

The outer blade shaft102may include a number of markings276defined on its outer surface208, as shownFIG. 11, which the surgeon may use to monitor the depth of the blade assembly14. The outer blade shaft102may also include one or more marking278, which indicate the orientation of the cutting slot16within the nasal passage. It should be appreciated that the marking278may also be used to monitor the depth of the blade assembly14. In the illustrative embodiment, the markings276,278are laser marked on the shaft102. In other embodiments, other methods, such as, for example, printing, may be used to affix the markings276,278on the shaft102. It should also be appreciated that the markings may be made fluorescent or visible in darkness.

The surgeon may toggle or press the control button62on the hand piece12to energize the motor66. The surgeon may also separately activate the vacuum pump48. When the motor66is energized, the motor66causes the output shaft92to rotate clockwise and counterclockwise. It should be appreciated that the motor66may operate a single, continuous speed or at a variable speed.

The rotation of the shaft92is transmitted to the inner collar80via the gear assembly90, thereby causing the inner collar80. The splined connection between the inner collar80and inner hub120of the blade assembly14causes the inner hub120(and hence the inner blade shaft100) to rotate. The hand piece12is configured to oscillate the direction of the motor66such that the inner blade shaft100oscillates clockwise and counter clockwise about its longitudinal axis to cut the tissue. It should be appreciated that the hand piece12may also be configured to rotate the motor66continuously in either direction.

To remove tissue, the distal end18of the blade assembly14is advanced into contact with the target tissue280. As described above, tissue is prevented from entering the passageway104by the closed distal tip228of the outer blade shaft102. Instead, as shown inFIG. 12, the tissue must be advanced into the cutting slot16. As the inner blade shaft100is rotated about its axis110by the motor66, the cutting edge106, for example, is advanced into engagement with the tissue280.

The movement of the inner blade shaft100in one direction presses the tissue280into engagement with the cutting edges108,114. The serrated teeth266of the inner blade shaft100and the serrated teeth236of the outer blade shaft102cooperate to slice the target tissue280. When the motor66reverses direction, the tissue280is pressed into engagement with the opposite cutting edges106,112. The serrated teeth266of the inner blade shaft100and the serrated teeth236of the outer blade shaft102then cooperate to slice the target tissue280. As the instrument10is cutting the tissue, the closed distal tip228and the recessed cutting edges112,114reduce the possibility of inadvertently cutting bone or overcutting the tissue.

As shown inFIG. 13, the severed portion282of the tissue is drawn into the passageway104through the opening184. When the vacuum pump48is activated, a suction air flow is created through the surgical instrument10. When the blade assembly14is attached to the hand piece12, the longitudinal passageway104of the inner blade shaft100is fluidly connected to the vacuum pump48via the hose46, the connectors36,42, and the passageways84,96. As a result, the severed tissue282or other particles entering the passageway104of the inner blade shaft100are drawn out of the surgical instrument10.

At the conclusion of surgery, the blade assembly14may be detached from the hand piece12. The hand piece12may be cleaned and reused. Similarly, the blade assembly14may be cleaned and reused or, alternatively, disposed of. New or other blade assembly configurations may be used in future surgeries.

The blade assembly14may be interchangeable with alternative blade assemblies including blade shafts of different configurations. For example, another combination of inner and outer blade shafts (hereinafter inner blade shaft300and outer blade shaft302) is shown inFIGS. 14-15. As shown inFIG. 14, the outer blade shaft302includes an elongated tube304with a stepped outer surface306. Like the elongated tube200, the elongated tube304extends from a distal end308to a proximal end (not shown). In the illustrative embodiment, the elongated tube304is formed from a metallic material such as, for example, stainless steel.

The tube304includes a cylindrical proximal section310and a distal section312. The distal section312includes a cylindrical outer surface314, which has an outer diameter316that is smaller than the outer diameter318of the proximal section310. In the illustrative embodiment, the outer diameter316of the distal section312is about 3 millimeters, and the outer diameter318of the proximal section310is about 4 millimeters. Additionally, the distal section312extends between about 18 and about 19 millimeters. In still other embodiments, the outer diameter of the proximal section may be smaller than the outer diameter of the distal section to, for example, facilitate suction and reduce the possibility of clogging in certain applications.

The sections310,312are formed separately from the same metallic material and later assembled by welding, press fit, or swaging. In other embodiments, the sections310,312may be formed as a single, monolithic component or the shaft102may be formed from additional pieces that are later assembled. Additionally, the sections310,312may be formed from different materials. For example, the distal section312may be formed from as a malleable or bendable section, and the proximal section310may be formed from a rigid or semi-rigid material.

The configuration of the cutting slot16of the outer blade shaft302is identical to the cutting slot described above in regard toFIGS. 1-13. As shown inFIG. 14, the cutting slot16opens into a longitudinal passageway320of the outer blade shaft102. The passageway320is defined by a cylindrical inner surface322and extends proximally to an opening (not shown) defined in the proximal end of the elongated tube304. The passageway320has a distal diameter324that is defined by the inner surface216. The diameter324is illustratively is equal to about 2.4 millimeters. The passageway320has an intermediate diameter326that is equal to about 2.7 millimeters. A third diameter328is defined in the proximal section310and is equal to about 3.8 millimeters.

Like the shaft102, the outer blade shaft302includes a closed distal tip330. The longitudinal passageway320is therefore not exposed or accessible through the tip330of the blade shaft302and access is permitted at the distal end308only through the cutting slot16in the outer surface306.

As described above, the outer blade shaft302may be combined with an inner blade shaft300. As shown inFIG. 15, the inner blade shaft300includes an elongated tube334with a stepped outer surface336. Like the elongated tube170of the shaft100, the elongated tube334extends from a distal end338to a proximal end (not shown). In the illustrative embodiment, the elongated tube334is formed from a metallic material such as, for example, stainless steel.

The tube334includes a cylindrical proximal section340, a distal section342, and an intermediate section344. The distal section342includes a cylindrical outer surface346, which has an outer diameter that is smaller than the outer diameter of the proximal section340but larger than the outer diameter of the intermediate section344. The sections340,342,344are formed separately from the same metallic material and later assembled by welding, press fit, or swaging. In other embodiments, the sections340,342,344may be formed as a single, monolithic component or the shaft300may be formed from additional pieces that are later assembled. Additionally, the sections340,342,344may be formed from different materials. For example, the sections340,342may be formed from a flexible or semi-flexible material such as a flextube, and the proximal section340may be formed from a rigid or semi-rigid material.

As shown inFIG. 15, the configuration of the cutting edges106,108and the distal opening184of the shaft300is identical to the configuration the cutting edges106,108and the distal opening184. The distal opening184opens into the longitudinal passageway354of the inner blade shaft300. The passageway354is defined by a stepped cylindrical inner surface356and extends proximally to an opening (not shown) defined in the proximal end of the elongated tube334. The passageway354has a distal diameter360that is equal to about 1.8 millimeters. The passageway354then expands to a proximal diameter362of about 2.9 millimeters in the proximal section340.

Like the blade assembly14, the inner blade shaft300may be secured to an inner hub120such that the blade shaft300may be rotated relative to the outer blade shaft302. Similarly, the outer blade shaft302may be secured to an outer hub122to form a blade assembly that is interchangeable with the blade assembly14. In use, the stepped passageway354of the inner blade shaft300creates a nozzle effect that improves the suction within the passageway354and reduces the possibility of clogging.

As described above, the blade assembly14may include an inner blade shaft (hereinafter inner blade shaft400) that includes a flexible or semiflexible section near its distal end. Referring now toFIG. 16, the inner blade shaft400includes an elongated tube402that extends from a distal end404to a proximal end (not shown). In the illustrative embodiment, the elongated tube402is formed from a metallic material such as, for example, stainless steel.

The tube402includes a distal section176, a cylindrical proximal section406, and an intermediate section408. The distal section176has an identical configuration to the distal section176of the inner blade shaft100. The intermediate section408includes a plurality of circumferential slots or openings410, which divide the section408into segments412and permit the intermediate section408to flex and bend. In the illustrative embodiment, the section408extends between about 2.0 and about 4.0 millimeters. The proximal section406is formed as a rigid or semi-rigid component. The sections176,406,408are formed separately from the same metallic material and later assembled by welding, press fit, or swaging. In other embodiments, the sections176,406,408may be formed from different materials, including, for example, polymeric materials.

As shown inFIG. 16, the shaft400includes a longitudinal passageway414similar to the longitudinal passageway104of the shaft100. To maintain the rate of suction in the inner blade shaft400, the passageway414may be encased by, for example, a polymer coating or tubing to seal the circumferential openings410of the intermediate section408.

In the illustrative embodiment, the passageway414has a constant diameter. In other embodiments, the passageway414and hence the tube200may include one or more stepped sections along its length. In still other embodiments, the tube402may taper along its length. In still other embodiments, the outer and inner diameters of the proximal section may be smaller than the outer and inner diameters of the distal section to, for example, facilitate suction and reduce the possibility of clogging in certain applications. In other embodiments, the distal section of the tube402may have outer and inner diameters smaller than the outer and inner diameters of proximal section to facilitate visualization of the surgical site and reduce the possibility of clogging in certain applications.

As described above, the inner blade shaft400may be used in conjunction with an outer blade shaft (hereinafter outer blade shaft502) that includes a malleable or bendable section near its distal end. Referring now toFIG. 17, the outer blade shaft502includes an elongated tube504that extends from a distal end506to a proximal end (not shown). In the illustrative embodiment, the elongated tube504is formed from a metallic material such as, for example, stainless steel.

The elongated tube504has a plurality of circumferential slots508positioned proximal of the cutting slot16. The slots508are sized and spaced to make the distal section510of the tube504bendable or malleable to permit the surgeon greater flexibility in positioning the blade assembly during surgery. The distal section510is configured to return to its substantially straight configuration following surgery. In the illustrative embodiment, the distal section510extends between about 2.0 and about 4.0 millimeters. It should be appreciated that the other aspects of the outer blade shaft502are substantially similar to the outer blade shaft102described above, including, for example, the closed distal tip228and the cutting slot16.

The shaft502includes a passageway sized to receive the inner blade shaft400. The passageway illustratively has a constant diameter. In other embodiments, the passageway414and hence the tube504may include one or more stepped sections along its length. In still other embodiments, the tube504may taper along its length. In still other embodiments, the outer and inner diameters of the proximal section may be smaller than the outer and inner diameters of the distal section to accommodate a similarly configured inner blade shaft. In other embodiments, the distal section of the tube504may have outer and inner diameters smaller than the outer and inner diameters of proximal section to facilitate visualization of the surgical site.

Referring now toFIGS. 18-19, another embodiment of a surgical instrument (hereinafter surgical instrument610) is shown. Some of the features of the embodiment ofFIGS. 18-19are similar to the embodiment described above. For such features, the references numbers from the embodiment described above will be used to identify those features inFIGS. 18-19. As shown inFIG. 18, the instrument610includes a hand piece612and a blade assembly614that extends outwardly from the hand piece612to a distal end618. In the illustrative embodiment, the blade assembly614is secured to the hand piece612and not configured to be detached. Additionally, the instrument610is configured to be disposed after a single use.

A cutting slot16is positioned at the distal end618of the blade assembly614. This embodiment of the surgical instrument is configured to be used with a cable drive mechanism620, which may be included in a portable surgical console. The cable drive mechanism620is used to operate the blade assembly620to shave or cut tissue within the cutting slot16. The surgical instrument610is also configured to be coupled to a negative pressure source such as a vacuum pump48to evacuate the severed tissue from the instrument610.

The hand piece612of the surgical instrument610includes an elongated body622. The body622is configured to be grasped by a user during operation of the surgical instrument610. The elongated body622may be formed from a plastic, rigid polymer, or other rigid materials.

As shown inFIG. 19, the blade assembly614extends outwardly from a longitudinal end632of the body622. The hand piece612also includes a connector36and a connector638, which are positioned at the opposite longitudinal end640of the body622. The connector36is configured to engage a hose connector42of the vacuum pump48such that the hand piece612(and hence the blade assembly614) may be connected to the vacuum pump48.

The connector638is configured to engage a connector642of the cable drive mechanism620. One such mechanism uses the bi-plex or tri-plex coil drive cables commercially available from Heraeus Medical Components. The connectors638,642also includes a pair of electrical contacts644, which permit the user to activate the cable drive mechanism620using the hand piece612.

As shown inFIGS. 18-19, the hand piece612also includes a control panel660positioned on the elongated body622. In the illustrative embodiment, the control panel660includes a single control button662, which may be toggled to activate the cable drive mechanism620. In this embodiment, the vacuum pump48may be activated using a foot pedal or switch located on the pump48. In other embodiments, the hand piece612may include additional controls such as toggles, levers, or other buttons. It should also be appreciated that in other embodiments the control panel660may be omitted from the hand piece612, and the cable drive mechanism620and the pump48may be activated using a foot pedal or other control device.

As shown inFIG. 19, the hand piece612includes an electrical contact switch70that is positioned in an inner chamber664of the elongated body622. When the button662is toggled or pressed by the user, the switch70is configured to generate an electrical output. The electrical output is relayed to the cable drive mechanism620via the contacts644and the connectors638,642.

The hand piece612also includes an input shaft668that is positioned in the inner chamber664. The input shaft668is configured to engage the connector642of the cable drive mechanism620within the connector638. When the cable drive mechanism620is activated, the connector642causes the input shaft668to rotate. The rotation of the input shaft668is transmitted to the blade assembly614via a gear assembly670.

As shown inFIG. 19, the gear assembly670includes an input gear672mounted to a distal end674of the input shaft668. The gear assembly670also includes an output gear676mounted to an inner blade shaft100of the blade assembly614. Each of the gears672,676is press fit onto its respective shaft668,100and includes a number of teeth678. The teeth678of the gears672,676are intermeshed such that rotation of the gear672causes rotation of the gear676(and hence inner blade shaft100). Each of the gears672,676and the input shaft668may be formed from a rigid polymeric material or a metallic material such as, for example, stainless steel.

The blade assembly614includes the inner blade shaft100and an outer blade shaft102that is secured to the hand piece612. In the illustrative embodiment, a proximal end680of the outer blade shaft102is press fit into a collar682secured to the elongated body622of the hand piece612. Similar to the embodiment described above, the inner blade shaft100extends outwardly from the proximal end680of the shaft102to a proximal end684that is fluidly coupled to the vacuum hose connector36. In that way, negative pressure may be created through the longitudinal passageway104to draw severed tissue from the distal end618of the blade assembly614, through the hand piece612, and out of the instrument610.

In the illustrative embodiment, the hand piece612also includes a biasing element such as, for example, a spring686that is engages the output gear676. The spring686biases the output gear676(and hence the inner blade shaft100) in a distal direction such that axial alignment between the distal opening184of the inner blade shaft100and the cutting slot16is maintained.

In use, the cable drive mechanism620and the vacuum pump48are activated as described above. The input shaft668is rotated by the cable drive mechanism620. The rotation of the input shaft668causes rotation of the gears672,676and hence the inner blade shaft100. Tissue positioned in the cutting slot16may be cut or severed by the two or more the cutting edges106,108,112,114of the shafts100,102. The severed tissue may be withdrawn from the blade assembly614and the instrument610via suction created by the vacuum pump48.

While the embodiment ofFIGS. 18-19is shown with the inner blade shaft100and the outer blade shaft102, it should be appreciated that any of the blade shaft designs described herein may be used with a cable-driven design, including, for example, the stepped blade shaft, flexible, and malleable designs. It should also be appreciated that the cable-drive mechanism may be incorporated into a reusable instrument and/or an instrument designed to use interchangeable blade assemblies.

Referring now toFIG. 20, another embodiment of a surgical instrument (hereinafter instrument710) is shown. Some of the features of the embodiment ofFIG. 20are similar to the embodiments described above. For such features, the references numbers from the embodiments described above will be used to identify those features inFIG. 20. As shown inFIG. 20, the instrument710includes a hand piece712and a blade assembly714that extends outwardly from the hand piece712to a distal end718. In the illustrative embodiment, the blade assembly714is secured to the hand piece712and not configured to be detached. Additionally, the instrument710is configured to be disposed after a single use.

The hand piece712of the surgical instrument710includes an elongated body722. The body722is configured to be grasped by a user during operation of the surgical instrument710. The elongated body722may be formed from a plastic, rigid polymer, or other rigid materials. A cutting slot716is positioned at the distal end718of the blade assembly714. This embodiment of the surgical instrument includes a hose724that is connected to a vacuum pump (not shown) and a cable726that is connected to an electrical source such as, for example, a wall outlet.

Like the instrument10, the instrument710includes an electric motor728that is configured to drive the blade assembly714. In this embodiment, the motor728may be activated using a control button62positioned on the hand piece712. A gear assembly (not shown) transmits the output of the motor728to the inner blade shaft100to cause the inner blade shaft100to rotate relative to the outer blade shaft102and thereby cut tissue.

It should be appreciated that the size and configuration of each of the instruments and blade assemblies described herein permit the devices to be portable and facilitate the ease of use of the device in surgical procedures.

While the disclosure has been illustrated and described in detail in the drawings and foregoing description, such an illustration and description is to be considered as exemplary and not restrictive in character, it being understood that only illustrative embodiments have been shown and described and that all changes and modifications that come within the spirit of the disclosure are desired to be protected. For example, it should be understood that the materials used to form the various surgical instruments described herein may be modified or changed to reduce the weight of the instrument and facilitate single-handed use. Similarly, other materials may be selected to reduce friction of the inner passageways and outer surfaces. Still other materials may be selected for their anti-reflective properties. Additionally, as described above, the materials used to form the distal ends of the inner and outer blade shafts are dissimilar metallic materials. It should be appreciated that in other embodiments other dissimilar materials may be used. In still other embodiments, the same materials may be used.