Patent Description:
The present invention is directed generally to a surgical cutting device and, more particularly, to surgical cutting device with a blade for cutting and removing cartilage from a diseased area.

A variety of conditions may negatively affect the human knee including arthritis, ligament instability, and localized trauma. These conditions may be surgically treated by repairing portions of the knee cartilage, meniscus, or ligaments or by replacing them with natural or artificial replacements. In such procedures, it is often necessary to correct the alignment of the knee to relieve pressure from the damaged portion of the joint and balance the load on the joint. In some instances, correcting the knee alignment alone, without additional repair or replacement of injured or diseased tissue, is sufficient to provide relief and improve function. Often, in a young arthritis patient, correcting the knee alignment may be a first surgical choice to provide years of relief prior to resorting to a more aggressive total knee replacement procedure. Typically, injured or diseased knees will develop a varus deformity in which the medial side of the person's knee joint has become compressed resulting in a bowlegged alignment of the lower limb.

A frequently used procedure to correct knee alignment is high tibial osteotomy. In this procedure, the knee alignment is changed by cutting the tibia on one side and then expanding or compressing the cut side to change the angle between the axes of the tibia and femur. For example, in a closing high tibial osteotomy, a wedge of bone is removed from the tibia and then the opposite sides of the cut are brought together to angle the tibia towards the side on which the cut was made. In an opening high tibial osteotomy, a cut is made partway across the tibia and the cut is opened to create a wedge-shaped gap thereby angling the tibia away from the side on which the cut was made. A fixturing device, such as a bone plate or external fixator, is then applied to the tibia to hold the tibial alignment until the bone heals. Typically, for opening high tibial osteotomy, bone is taken from the patient's pelvis and applied to the gap in the tibia to aid in bone healing. An opening high tibial osteotomy may be performed on the medial side of a patient's knee to treat a varus deformity.

Another procedure used to correct knee alignment is a distal femoral osteotomy. For example, in an opening lateral distal femoral osteotomy, a cut is made partway across the femur from the lateral side and the cut is opened to create a wedge-shaped gap thereby angling the femur away from the lateral side.

It is often necessary to use powered tissue cutting tools in order to perform surgical procedures. Such tools generally comprise a handpiece which cyclically moves a tissue cutting device such as a blade or burr in some oscillating or reciprocating manner. The handpiece generally includes a pneumatic or electric drive motor having an output shaft to which the cutting device is attached, the shaft being axially aligned with a drive axis of the handpiece. As used herein, the term "drive axis" refers to the axis of the motor output shaft through which power is delivered from the motor. The handpiece may be a "pencil" type handpiece in which the body is elongated and the drive axis is aligned with the axis of the body or a pistol-grip type of handpiece in which the drive axis is aligned in a chosen direction relative to the grip. The drive motor of the handpiece produces a driving force which reciprocates the output shaft and cutting device either longitudinally, i.e. linearly along the drive axis (like a saber saw), or arcuately in a plane perpendicular to the drive axis. Handpieces utilizing the former type of action are generally referred to as reciprocating saws while those utilizing the latter action are generally referred to as oscillating saws. In some cases an oscillating saw may transfer the oscillating drive motion so that it is cyclical within a plane parallel to the axis of the elongated body of the handpiece. A sagittal saw is a type of oscillatory saw in which the cyclical reciprocating action is in a plane aligned with the drive axis.

In all instances, numerous conventional tissue cutting blades or burrs or other devices (all collectively referred to herein as "blades") are adapted to be secured to the handpiece via a collet mechanism which is utilized to selectively attach and release a desired blade. A variety of different cuts can be made with a single saw depending upon the shape of the blade. For oscillating saws, the blades are often in the form of a flat, elongated body having a cutting edge (e.g. teeth, abrader, etc.) at one end and a hub at the other end, the hub being shaped and adapted to fit the particular collet. Such flat blades are used to make cuts in a plane perpendicular to the drive axis. An oscillating saw may also be used for effecting cuts in a plane parallel to the handpiece axis by attaching a transverse hub to a flat blade. A crescentic blade having a curved instead of a flat body may be used for curved cuts. The body of a crescentic blade has teeth (or another cutting edge) at its distal end which follow the shape of the arcuate body so that as the blade oscillates about the axis, the teeth follow an arcuate pattern having a center of curvature on the axis. Some flat blades may have the cutting edge at an angle to the blade body to make cuts in an angled plane. Angled blades may have an axially elongated body either on or off the blade axis. That is, the proximal end of the blade body may have a transverse hub or it may simply be attached in-line with the drive axis. The resulting cut is arcuate and facing away from the axis.

Any of the blades described above may be used to make cuts into the bone. However, in most surgical procedures involving the knee (or foot, angle, hand and/or wrist), damage or diseased cartilage may also need to be removed from the surgical site for proper repair of a particular surgical site.

Therefore, there is a need for a tool that is specialized for cutting and removing diseased cartilage.

<CIT> discloses a surgical cutting device which forms the basis for the two-part form of present claim <NUM>. Other conventional cutting devices are described in <CIT>, <CIT>, <CIT> and <CIT>.

Embodiments of the present invention are directed to a surgical cutting device for cutting and removing cartilage from a diseased area. In particular, embodiments of the present invention are used to cut and scrape away diseased or damaged cartilage (e.g., in extremities procedures (foot and ankle / hand and wrist). According to one aspect, the surgical cutting device includes an elongated shaft having a proximal portion and a distal narrowing portion connected between a proximal end and a distal end. A central longitudinal axis extends through the elongated shaft. The proximal portion has a first diameter and the distal narrowing portion has a second diameter. The first diameter is larger than the second diameter. The cutting device also includes a cutting tip at the distal end of the elongated shaft. The cutting tip extends at an angle relative to the central longitudinal axis and includes a curved blade.

According to another aspect, the surgical cutting device includes an elongated shaft having a proximal portion and a distal narrowing portion connected between a proximal end and a distal end. A central longitudinal first axis extends through the elongated shaft. The surgical cutting device also includes a cutting tip at the distal end of the elongated shaft. The cutting tip extends along a second axis, which is at an angle relative to the central longitudinal first axis. The cutting tip comprises a curved blade which is open in a proximal direction.

The surgical cutting device can also include a handle attached at the proximal end of the elongated shaft.

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

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

Referring now to the figures, wherein like reference numerals refer to like parts throughout, <FIG> shows a side perspective view schematic representation of a cutting device <NUM>, according to an embodiment. The cutting device <NUM> comprises an elongated shaft <NUM> extending along a central longitudinal y - y axis between a proximal end <NUM> and a distal end <NUM>. In the depicted embodiment, the elongated shaft <NUM> is cylindrical; however, any other suitable geometry may be used. The elongated shaft <NUM> may have a uniform diameter or a varied diameter. In the depicted embodiment, the elongated shaft <NUM> has a first diameter and a second diameter that is different from the first diameter.

As shown in <FIG>, the elongated shaft <NUM> has proximal portion <NUM> and a distal portion <NUM> (which can be narrowing and taper in the distal direction, but does not need to be). The proximal portion <NUM> has the first diameter and the distal narrowing portion <NUM> has the second diameter. In the depicted embodiment, the second diameter of the distal narrowing portion <NUM> is smaller than the first diameter of the proximal portion <NUM>. In an embodiment, the distal narrowing portion <NUM> can be tapered in the distal direction and the second diameter is any diameter along the distal narrowing portion <NUM>. The narrowing portion <NUM> allows the cutting device <NUM> to access and cut smaller surgical areas, such as in the hand and wrist.

Turning now to <FIG>, there is shown a close-up, side perspective view schematic representation of the distal end <NUM> of the cutting device <NUM>, according to an embodiment. The narrowing portion <NUM> of the elongated shaft <NUM> extends to the distal end <NUM>. The distal end <NUM> comprises a cutting tip <NUM>, as shown in <FIG>. In the depicted embodiment, the cutting tip <NUM> extends along an x - x axis. In general, the cutting tip <NUM> extends at angle relative to the central longitudinal y - y axis (which extends through the elongated shaft <NUM>). In <FIG>, the cutting tip <NUM> extends at an angle greater than <NUM> degrees relative to the central longitudinal y - y axis.

Still referring to <FIG>, the cutting tip <NUM> comprises a curved blade <NUM>. In the depicted embodiment, the curved blade <NUM> has a semi-circular cross-section such that the curved blade <NUM> is crescent-shaped and open toward the proximal direction. The curved blade <NUM> comprises an inner wall <NUM> extending to a flat, semi-circular base <NUM>. Further, the base <NUM> of the curved blade <NUM> extends to and abuts a flat portion <NUM> of the cutting tip <NUM>. In the depicted embodiment, the flat portion <NUM> is D-shaped and extends proximally.

In the embodiment depicted in <FIG>, the base <NUM> of the curved blade <NUM> and the flat portion <NUM> are connected at a flange <NUM> or edge. The base <NUM> extends at an angle relative to the flat portion <NUM>. In an embodiment, the flat portion <NUM> extends along both a plane and an axis (z - z axis) that are substantially parallel to the central longitudinal y - y axis, while the base <NUM> extends along a plane and axis that is transverse to both the central longitudinal y - y axis and the x - x axis. In one embodiment, the base <NUM> extends along an axis which is substantially perpendicular to the x - x axis. The angular configuration and curvature of the cutting tip <NUM> is optimized for use in hand and wrist procedures.

Referring now to <FIG>, there is shown a side view schematic representation of a cutting device <NUM>, according to an alternative embodiment. In the depicted embodiment, the proximal end <NUM> of the cutting device <NUM> comprises a handle <NUM>. In accordance with an embodiment, there is no motor or automated actuation for the described device <NUM>, which include curved blade(s) or cutting tip on a shaft that will be stuck into a handle <NUM> so the surgeon can cut and pry and scrape away cartilage. Thus, the cutting device <NUM> can be manipulated directly by the user via the handle <NUM> (or otherwise at the proximal end <NUM> of the device <NUM>).

Similar to the embodiment shown in <FIG> and <FIG>, the embodiment of the cutting device <NUM> in <FIG> comprises an elongated shaft <NUM> extending along a central longitudinal y - y axis between a proximal end <NUM> and a distal end <NUM>. The elongated shaft <NUM> may be cylindrical and have a uniform diameter or a varied diameter, as described above. As also similar to the embodiment shown in <FIG> and <FIG>, the elongated shaft <NUM> of the cutting device <NUM> in <FIG> comprises a proximal portion <NUM> and a distal narrowing portion <NUM>. As shown, the distal narrowing portion <NUM> is tapered in the distal direction. The distal narrowing portion <NUM> allows the cutting device <NUM> to access and cut small surgical areas, such as in the foot and ankle.

The distal end <NUM> of the cutting device <NUM> comprises a cutting tip <NUM>. In the depicted embodiment, the cutting tip <NUM> extends along an x - x axis. In general, the cutting tip <NUM> extends at angle relative to the central longitudinal y - y axis (which extends through the elongated shaft <NUM>). In <FIG>, the cutting tip <NUM> extends at an angle greater than <NUM> degrees relative to the central longitudinal y - y axis. The cutting tip <NUM> in <FIG> is configured and optimized for use in foot and ankle procedures. For example, the cutting tip <NUM> is longer than the cutting tip <NUM> in the embodiment in <FIG> and <FIG>. Accordingly, the cutting tip <NUM> of the cutting device <NUM> in <FIG> and <FIG> varies from that shown in <FIG> and <FIG>.

Turning now to <FIG>, there is shown a close-up, side perspective view schematic representation of the distal end <NUM> of the cutting device <NUM>, according to an alternative embodiment. As shown in <FIG>, the cutting tip <NUM> comprises a curved blade <NUM> which is open in the proximal direction. In the depicted embodiment, the curved blade <NUM> has a semi-circular cross-section such that the curved blade <NUM> is crescent-shaped. The curved blade <NUM> comprises an inner wall <NUM> extending to a base <NUM>. The base <NUM> in the embodiment shown in <FIG> is sloped, extending toward the central longitudinal y - y axis (and elongated shaft <NUM>). Further, the sloped base <NUM> of the curved blade <NUM> extends to and abuts a flat portion <NUM> of the cutting tip <NUM>. In the depicted embodiment, the flat portion <NUM> is circular or semi-circular and extends proximally.

In the embodiment depicted in <FIG>, the base <NUM> of the curved blade <NUM> slopes or extends to the flat portion <NUM> of the curved blade <NUM>. The base <NUM> also extends at least partially around the flat portion <NUM>, as shown in <FIG>. The flat portion <NUM> extends along a plane and a z - z axis, which are substantially parallel to the central longitudinal y - y axis, as shown in <FIG>. The angular configuration and curvature of the cutting tip <NUM> is optimized for use in foot and ankle procedures.

While various embodiments have been described and illustrated herein, those of ordinary skill in the art will readily envision a variety of other means and/or structures for performing the function and/or obtaining the results and/or one or more of the advantages described herein. More generally, those skilled in the art will readily appreciate that all parameters, dimensions, materials, and configurations described herein are meant to be exemplary and that the actual parameters, dimensions, materials, and/or configurations will depend upon the specific application or applications for which the teachings is/are used. Those skilled in the art will recognize, or be able to ascertain using no more than routine experimentation, many equivalents to the specific embodiments described herein. It is, therefore, to be understood that the foregoing embodiments are presented by way of example only and that, within the scope of the appended claims, embodiments may be practiced otherwise than as specifically described and claimed.

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

Claim 1:
A surgical cutting device (<NUM>), comprising:
an elongated shaft (<NUM>) having a proximal portion (<NUM>) and a distal portion (<NUM>) connected between a proximal end (<NUM>) and a distal end (<NUM>);
a central longitudinal axis (y-y) extending through the elongated shaft (<NUM>);
wherein the proximal portion (<NUM>) has a first diameter and the distal portion (<NUM>) has a second diameter, the first diameter being larger than the second diameter;
a cutting tip (<NUM>) at the distal end (<NUM>) of the elongated shaft (<NUM>), extending along a second axis (x-x), at an angle relative to the central longitudinal axis (y-y);
wherein the cutting tip (<NUM>) comprises a curved blade (<NUM>) which is open in a proximal direction;
wherein the curved blade (<NUM>) comprises an inner wall (<NUM>) extending to a base (<NUM>) of the cutting tip (<NUM>),
characterized in that a cross-section of the curved blade (<NUM>) in a plane perpendicular to the second axis (x-x) is crescent-shaped, and the base (<NUM>) is semi-circular.