Eccentric rotary cutting tool

Abstract

A surgical tool (10) and method for removing bone in which a working end (20) of the tool rotates eccentrically with one or more cutting edges (24) such that, in a first position, the one or more cutting edges (24) are occluded by one or more surfaces of a distal end portion (14) of a body (11) of the tool, and, in a second position, the one or more cutting edges (24) are occluded by one or more surfaces of a distal end portion (14) of the body (11) of the tool. At least one or more of the one or more cutting edges (24) is exposed for cutting bone in contact with the at least one or more cutting edges. The body (11) has a foot plate (18) that guides the positioning of the working end (20) and protects soft tissue and adjacent structures while removing bone.

Description

Background Technology

[0001] This disclosure generally relates to a handheld surgical device configured to perform one or more surgical procedures, and more specifically, to a device configured to remove small pieces of bone during one or more surgical procedures.

[0002] The Kerrison punch is a commonly used tool in spinal surgery and has been in use for over 100 years. During surgery, the punch involves repeatedly squeezing the handle to dislodge bone. The punching motion of the Kerrison punch can compress and tear unwanted tissue, including nerves, blood vessels, and / or the spinal cord. Furthermore, the repetitive squeezing motion can fatigue the surgeon; therefore, the likelihood of compressing or tearing tissue increases with fatigue and hand spasms.

[0003] Using a punch to remove bone is a slow process. The typical sequence of this process is to insert the footer under the edge of the bone to be removed, squeeze the handle to break off small pieces of bone, remove the tool from the site, wipe the removed bone out of the tool, and rinse and repeat the sequence. Sometimes this sequence is performed hundreds of times until enough bone is removed before that part of the surgery is considered complete. Summary of the Invention

[0004] One aspect of this disclosure relates to a surgical tool for cutting bone, the surgical tool comprising: a body including a proximal end and a distal end, and having a length extending between the proximal end and the distal end, wherein an opening is provided in the distal end and the distal end terminates in a foot plate; a rotatable shaft supported within the body in an operably oriented manner; a working end disposed on the distal end of the rotatable shaft and positioned at least partially together with the opening in the distal end of the body, wherein the working end includes one or more cutting edges; and wherein the working end is eccentrically rotated such that: in a first position, one or more cutting surfaces of the working end are protected by one or more surfaces of the distal end of the body, and in a second position, one or more of the one or more surfaces of the distal end are exposed.

[0005] The footplate is a vertical footplate, positioned at an angle relative to the horizontal axis of the length extending between the proximal and distal ends of the body.

[0006] In one or more embodiments, the footplate is positioned at an angle ranging from about 30 degrees to about 90 degrees or greater.

[0007] In one or more embodiments, the working end includes a plurality of cutting edges that are spaced apart along the length of the working end. The working end includes a plurality of cutting edges at one or more locations along the length of the working end.

[0008] The distal end of the surgical instrument has an arc or bow shape, and an opening spans the top and at least one side of the distal end.

[0009] Another aspect of this disclosure relates to a method for bone removal. Bone removal includes inserting a distal end of a surgical device into a selected space between a portion of the bone to be removed and adjacent tissue, and using angled footplates of the distal end of the surgical device to guide the device into the selected space and / or protect adjacent tissue while removing the bone. The surgical device is actuated and its working end is rotated to periodically expose one or more cutting surfaces to the bone for cutting, and the device is slid along the bone to continue bone removal without removing it from the selected space or adjacent selected spaces.

[0010] When the distal end of the surgical device is inserted into the space, the cutting surface of the working end is present in the distal end of the surgical device, but remains shielded by one or more surfaces of the distal end.

[0011] Another aspect of this disclosure relates to a surgical instrument having a working end, the working end including an opening and one or more shielding surfaces for one or more cutting surfaces, the one or more cutting surfaces being eccentrically rotatable about a longitudinal axis of the working end such that when the one or more cutting surfaces are stationary, the one or more cutting surfaces are shielded by the one or more shielding surfaces, and when the one or more cutting surfaces rotate, the one or more cutting surfaces are periodically exposed at the opening, the working end also including a footplate for performing one or more of the following: guiding the insertion of the surgical instrument, protecting one or more tissues adjacent to the area to be contacted with the one or more cutting surfaces.

[0012] The foot plate is positioned at an angle relative to the longitudinal axis of the working end, with the angle ranging from approximately 30 degrees to approximately 90 degrees.

[0013] In one or more embodiments, the footplate is removable from the working end. In one or more embodiments, the footplate is integral with the working end and cannot be removed from the working end.

[0014] The surgical instrument includes a body that houses a rotatable shaft for operably connecting to one or more cutting surfaces at a working end.

[0015] In one or more embodiments, the working end can be removed from the main body.

[0016] In one or more embodiments, the working end is integrated with the body and / or the rotatable shaft. Attached Figure Description

[0017] Figure 1 A powered rotary cutting tool is shown.

[0018] Figure 2 This is a cross-sectional side view of the cutting tool, with the working end in the parking position.

[0019] Figure 3 It is a 3D view of the cutting tool, in which the working end is in the running position.

[0020] Figure 4 This is a top-down 3D view of the workpiece.

[0021] Figure 5 This is a top-view perspective view of another embodiment of the working end.

[0022] Figure 6 This is a top-view perspective view of another embodiment of the working end.

[0023] Figure 7 It is a bottom-view 3D view of the working end.

[0024] Figure 8 This is a side perspective view of another embodiment of the working end.

[0025] Figure 9 The cutting tool is shown positioned between the bone spur and adjacent tissue. Detailed Implementation

[0026] This disclosure includes a surgical tool. The surgical tool is a powered rotary tool that provides one or more axially eccentric cutting edges. As described herein, the powered rotary tool is designed for bone removal. One or more cutting edges of the tool are rotatable to remove a portion of bone during surgical procedures. Although the device of this disclosure is illustrated by way of bone removal, the device and the concepts associated with it can be used and / or applied to any surgical procedure requiring the cutting and / or removal of tissue or other structures from a patient.

[0027] The device includes a body that allows the device to be held in the hand. The body typically has a first proximal end for gripping and a second distal end, the second distal end having an opening for access to the working end of a rotatable shaft. The distal end also terminates in a foot plate. The foot plate may be positioned at the end of the body to provide an end wall to the opening, which provides a channel for contact with the working end or otherwise exposes the working end.

[0028] The footplate can be angled relative to the body, allowing the device to slide into the space between the bone and adjacent tissue. The footplate can also function as a guide for positioning the bone to contact one or more exposed cutting edges. Furthermore, the device can slide along the bone to remove selected bone areas, eliminating the need to remove and / or clean the device between incisions.

[0029] The body houses a rotatable shaft, and the end of the shaft includes a working end. As described herein, the working end includes one or more cutting edges, also referred to as cutting surfaces. The working end of the shaft rotates within the distal end of the device, but as the working end rotates, the cutting edges of the working end are exposed at one or more openings in the distal end of the body of the device for cutting bone. The openings in the distal end may be located in the upper surface of the distal end and / or along one or more sides of the distal end.

[0030] More specifically, the working end can be an axially eccentric working end. When the device is powered off, the working end is precisely positioned such that one or more cutting edges are positioned in a predetermined resting position. In this resting position, the working end is substantially enclosed or otherwise concealed within the distal end of the body, and one or more cutting edges are not exposed. The distal end can be tubular, as the working end is at least partially housed within it. The distal end can be rounded or arcuate on at least one outer surface. For example, the distal end can have an arcuate cross-sectional shape along at least a portion (e.g., the bottom). This allows the device to be positioned within a wound or surgical site and / or otherwise slid to a position close to the bone for cutting without damaging adjacent structures. Upon actuation, one or more cutting edges rotate, and during rotation, one or more cutting edges are periodically exposed at the opening and / or extend through the opening. This allows one or more cutting edges to be exposed and allows direct contact between one or more cutting edges and the bone being cut. The working end does not retract into the length of the body to conceal itself.

[0031] In one or more embodiments, the distal end of the body includes a thin foot plate with a reduced thickness compared to a manual punching tool. The foot plate is thin enough to slide into place with minimal interference to adjacent structures, yet thick enough to accommodate cutting edges and protect adjacent structures from damage. The thickness of the foot plate can vary and / or be proportional to the diameter of one or more cutting edges and / or the working end. The thickness can vary relative to the varying diameter or size of one or more cutting edges and / or can be varied to achieve fitting into space while withstanding the manual force applied for positioning and / or cutting. The distal end may terminate in the vertical foot plate, with or without sidewalls along the distal end. The foot plate may also be angled relative to an axis along the length of the body of the device.

[0032] The thickness of the footplate can range from about 0.025 inches (about 0.65 mm) to about 0.075 inches (about 2.1 mm), and / or otherwise sufficiently to reduce the likelihood of inadvertently gripping soft tissue or compressing underlying structures during use of the device. In another embodiment, the thickness of the footplate is less than about 0.075 inches. The thickness can also vary to withstand the forces applied when the distal end is fitted into the space near the bone to be cut and / or vary in combination with the dimensions of one or more cutting surfaces. The distal end of the device does not include a hemispherical bowl-shaped portion, nor does the sleeve of the device terminate in such a bowl-shaped portion. Instead, the device includes a distal end that terminates in an angled footplate and may have an upper opening and one or more side openings. In one or more embodiments, the distal end includes a base plate and a footplate. The base plate may have an arcuate length portion. In some embodiments, the distal end includes a base plate, a footplate, and one or two opposing sidewalls. The footplate may be angled relative to an axis extending along the length portion of the device, such that the footplate can be positioned at approximately a 45-degree angle to the long axis of the sleeve. However, the footplate can be configured to have different angles relative to the long axis from 0 degrees to 90 degrees, including but not limited to 90 degrees or 30 degrees.

[0033] The footplate can also be integrally formed with or removably attached to the distal end of the device. For example, the footplate can be removable because the device can be configured as a system with multiple footplates, which can have the same or different constructions or sizes. Therefore, if a footplate is damaged, it can be easily replaced. Alternatively or additionally, footplates of different thicknesses and / or angles can be interchanged for customized cutting and / or matching of patient anatomy. Mechanical devices for removably securing the footplate to the distal end include, but are not limited to, friction joints, sliding channels with mating dimensions, clips, screws, etc.

[0034] The handle portion of the device includes a motor operably connected to a shaft having a working end. The motor is powered to rotate the shaft and the working end, causing an offset opening to expose a rotating cutting surface to the bone and remove it. The motor can be electrically driven, such as AC / DC driven, pneumatically driven, or vacuum driven. The motor can be housed within the handle or otherwise operably connected to the shaft housed within the handle.

[0035] In one or more embodiments, the device may be a battery-powered device, wherein the handheld device includes a motor and control software for actuating the motor. The battery may also be disposed within the handheld component or otherwise operably coupled to the handheld component. The handheld device is battery-powered, and the working end of the device can be attached to a rotating shaft for use. Then, in one or more embodiments, the working end may have one or more interchangeable cutting surfaces.

[0036] The device is typically configured to accommodate the typical rotational speed of the shaft and thus the typical rotational speed of the working end, which may vary but is generally in the range of approximately 60,000 to 75,000 RPM. The device is also configured to "park" the working end in a selected mating or parking position that does not expose one or more cutting edges outside the body of the device, allowing the footplate to be positioned as needed under, for example, bone or other structures to be cut. Once actuated and the working end is rotating or spinning, one or more cutting edges are subsequently exposed at or through one or more openings in the distal end and thus rotate to contact the bone to scrape or cut it.

[0037] More specifically, the working end of the device may include one, two, three, or more cutting edges or cutting surfaces. Typically, the working end and / or cutting edges are made of medical-grade materials, such as stainless steel. One or more cutting edges may be configured to rotate eccentrically.

[0038] The working end may include a small amount of metal that is ground off on the side opposite to the cutting or grinding end to allow for shaft balance.

[0039] The rear stop can also be set on the working end to provide rigidity to the position on the foot plate, thereby allowing for a reduction in the thickness of the foot plate.

[0040] In use, for example, the device can be used to laterally cut bone or bone spurs. Additionally, bone can be delivered to the top and / or side of the distal end to contact the rotating working end, thereby removing the bone. A footplate can facilitate this sliding placement. The device can be inserted beneath the tissue to be removed (e.g., a bone spur) and positioned between the bone spur and adjacent structures (e.g., a compressive nerve beneath the bone spur). As the working end rotates, the bone spur is removed, and the nerve beneath the bone spur is protected by at least a portion of the distal end of the device.

[0041] Bone fragments from the cutting action, also known as "shavings," resemble sawdust in appearance and can be extracted from the bone when using the device described herein. Unlike prior art devices where the device must be removed and cleaned for each bone spur, the device described herein allows the working end to gently slide into the subsequent area for bone removal without removing the tool from the wound or surgical site. This eliminates the constant feed and withdrawal of the cutting tool and significantly reduces surgical time. The device disclosed herein is designed to generally increase surgical safety.

[0042] Figures 1 to 4 The image shows a handheld surgical device 10 and its working end 20. The handheld surgical device 10 has a body 11 with a proximal end 12 and a distal end 14. The proximal end 12 includes a handle 16 configured to be held comfortably by the operator's hand when using the handheld surgical device 10. The distal end 14 terminates in a foot plate 18 and includes the working end 20. At least a portion of the working end 20 is configured for insertion into a wound or anatomical region to perform functions such as cutting bone during surgery.

[0043] A switch is supported at the proximal end 12 of the handheld surgical device 10, and the switch is located at or near the handle 16. Although not shown, the switch may be located in different positions, such as along the length of the device 10 or at the distal end 14. The switch is connected to a control unit in the handle 16, which is connected to a motor, which in turn is connected to a rotation shaft 30 inside the length or neck portion of the device 10. The working end 20 may include a small amount of metal 32 that is ground off on the side opposite to the cutting or grinding end to allow for shaft balance.

[0044] When the switch is activated, the control unit supplies power to the motor to rotate the shaft 30. When the shaft terminates at or is otherwise coupled to the working end 20, the working end 20 rotates together with the rotatable shaft 30.

[0045] The distal end portion 14 includes a foot plate 18, and the distal end portion 14 may terminate at the foot plate 18, the foot plate 18 being angled relative to an axis 19 extending along the length of the body 11. One or more openings 22 in the distal end portion 14 expose the working end 20 of the device 10, and when the working end 20 is rotated, one or more openings 22 in the distal end portion 14 expose one or more cutting edges 24 of the working end 20. The working end 20 includes one, two, three or more cutting edges 24.

[0046] In such Figure 1 and Figure 2In the first parking position shown, one or more cutting edges 24 are contained within or otherwise not exposed by or through the opening 22. One or more cutting edges 24 are protected by the sides of the distal end 14, thereby preventing contact between the cutting edges 24 and bone or other internal tissues due to the sides 24 of the distal end 14 and the footplate 18. Figure 3 In the second drive position shown, the working end 20 rotates, and thus, as the working end 20 rotates, one or more cutting edges 24 are periodically exposed at or through the opening 22. The one or more cutting edges 24 are rotated to be exposed at or along the opening 22 in the distal end 14 of the device 10, and as the one or more cutting edges are exposed and rotated, bone or structures in contact with the one or more cutting edges are removed.

[0047] More specifically, the working portion 20 is located at or near the distal end of the rotating shaft 30, or is otherwise connected to the distal end of the shaft 30. In some embodiments, the working portion 20 is attached to the shaft in a removable manner, such that the working portion 20 can be replaced.

[0048] The working end 20 has a proximal end 34, which is opposite to the distal end 36 of the working end 20 itself. The working end 20 may have one, two, three, or more cutting edges or cutting surfaces 24, and these cutting edges or cutting surfaces 24 may be positioned at or near the distal end 36 of the working end 20, and / or along the length 38 of the working end 20. The length 38 of the working end 20 may taper away from the proximal end 34 and the axis of rotation 30 at a shoulder 40. This allows one or more cutting edges or cutting surfaces 24 to rotate eccentrically because the cross-section of the length 38 is smaller than the cross-section of the shoulder 40 and the axis of rotation 30 at one or more locations. The cross-section of the length 38 may be symmetrical or may be asymmetrical.

[0049] like Figure 4 As further described in detail, the working end 20 may have a generally flat length portion 138, wherein the distal end portion 136 of the working end 20 is arc-shaped to provide a grinding surface 24, which serves as a cutting end during rotation. Similarly, when the working end 20 is rotated for cutting, the side edges 140 of the flat length portion 138 are exposed. Figure 1 and Figure 2 In the middle, the working end is in a parked, unexposed position, and... Figure 3 In this process, the cutting edges are rotated to expose one or more cutting edges 24. For example... Figure 4 As shown in further detail, the distal end 136 may terminate at a tapered edge 137 to set the cutting edge 24 at the protruding edge or forward edge 137.

[0050] like Figure 5 As further described in detail, in one or more embodiments, the working end 120 may also include a lip portion 140 that extends outward along one side of the length portion 138. The width of the channel 140 is smaller than the width of the length portion 138, and it may be positioned on one side or at the center of the length portion 138, and extends partially or substantially along the length portion 138. When the working end 120 rotates, the channel 140 is also exposed as a cutting edge 24.

[0051] Another embodiment of the working terminal is in Figure 6 and Figure 7 The working end 220 is shown at point 220. Alternatively, the working end 220 may have a concave length portion 238, which has an arcuate region near the end of the working end 20. Along the length portion 238, the concave segment may be smooth and arcuate, or, as shown, the concave segment may have angled inclined sides to provide a “V”-shaped channel 240 along the length portion 238, such that a cutting edge or cutting surface 24 is provided on the peripheral sides and bottom apex 242 of the length portion 238, which are exposed when the working end 220 rotates.

[0052] Channel 240 includes an inclined surface that provides a cutting edge 24, which is formed by abutting the inclined surface at an angle of 10 degrees, 20 degrees, or greater. Working end 220 can be considered biplanar, having a central ridge at its highest point. The leading edge 236 of working end 220 can be arc-shaped.

[0053] Another embodiment of the working terminal is in Figure 8 Shown at 320. The working end 320 may include an arcuate rear edge 322 and an angled front edge 324, the angled front edge 324 providing a cutting surface 24 when rotated in the distal end 14 of the body of the device 10. The front edge 326 may be tapered and arcuate to provide another cutting edge 24 as the working end 320 rotates. As the length portion 338 extends from the rotation axis 30, the length portion 338 of the working end 320 may be off-center in positioning, such that when the working end 320 is in the parked position in the device 10, the distal end 14 has one or more surfaces that obscure the cutting edges 24, and as... Figure 9 As shown, when the working end 320 rotates, the edge 24 is exposed for cutting the material in contact with the edge 24.

[0054] Figure 9A method is shown for positioning a device 10 having working ends 20, 120, 220, 320 between a material to be cut (e.g., a bone spur 50) and an adjacent structure (e.g., a nerve 52). As the working ends 20, 120, 220, 320 rotate, the distal end 14 slides along the bone spur 50 to remove excess bone and exposes one or more cutting edges 24 to remove bone in contact with one or more cutting edges 24.

[0055] Although this disclosure has been described with reference to preferred embodiments, those skilled in the art will recognize that changes in form and detail may be made without departing from the spirit and scope of this disclosure.

Claims

1. A surgical device for cutting bone, comprising: The body includes a proximal end and a distal end, and has a length portion extending between the proximal end and the distal end, wherein the distal end has an opening disposed therein and terminates in a foot plate; A rotatable shaft, which is operably supported within the body; A working end, disposed on the distal end of the rotatable shaft and positioned at least partially together with the opening in the distal end of the body, wherein the working end includes one or more cutting edges; and The working end is rotated eccentrically such that: in a first position, the one or more cutting surfaces of the working end are protected by one or more surfaces of the distal end of the body, and in a second position, one or more of the one or more surfaces of the distal end are exposed.

2. The surgical device according to claim 1, wherein, The foot plate is a vertical foot plate, which is positioned at an angle relative to the horizontal axis of the length portion extending between the proximal and distal ends of the body.

3. The surgical device according to claim 2, wherein, The footplate is set at an angle of about 30 degrees to about 90 degrees or greater.

4. The surgical device according to claim 1, wherein, The foot plate has a thickness of less than about 0.075 inches.

5. The surgical device according to claim 1, wherein, The working end includes multiple cutting edges that are spaced apart along the length of the working end.

6. The surgical device according to claim 1, wherein, The working end includes multiple cutting edges at one or more locations along the length of the working end.

7. The surgical device according to claim 1, wherein, The distal end of the body has an arcuate shape, and the opening spans the top and at least one side of the distal end.

8. The surgical device according to claim 1, wherein, The footplate is detachable from the main body.

9. A method for removing bone, comprising: Insert the distal end of the surgical device into a selected space between a portion of the bone to be removed and adjacent tissue; When removing bone, the angled footplate at the distal end of the surgical device is used to guide the surgical device into the selected space and / or protect the adjacent tissue; The surgical device is actuated and its working end is rotated to periodically expose one or more cutting surfaces to the bone for cutting the bone; as well as Without removing the surgical device from the selected space or an adjacent selected space, the surgical device is slid along the bone to continue removing the bone.

10. The method according to claim 9, wherein, When the distal end of the surgical device is inserted into the space, the cutting surface of the working end is present in the distal end of the surgical device, but remains obscured by one or more surfaces of the distal end.

11. A surgical instrument having a working end, the working end including an opening and one or more shielding surfaces for one or more cutting surfaces, the one or more cutting surfaces being eccentrically rotatable about a longitudinal axis of the working end such that when the one or more cutting surfaces are stationary, the one or more cutting surfaces are shielded by the one or more shielding surfaces, and when the one or more cutting surfaces rotate, the one or more cutting surfaces are periodically exposed at the opening, the working end further including a foot plate for performing one or more of the following: guiding insertion of the surgical instrument, protecting one or more structures adjacent to the area to be contacted with the one or more cutting surfaces.

12. The surgical instrument according to claim 11, wherein, The foot plate is positioned at an angle relative to the longitudinal axis of the working end, the angle being in the range of about 30 degrees to about 90 degrees.

13. The surgical instrument according to claim 11, wherein, The foot plate can be removed from the working end.

14. The surgical instrument according to claim 11, wherein, The surgical tool also includes a body that houses a rotatable shaft for operably connecting to the one or more cutting surfaces of the working end.

15. The surgical instrument according to claim 14, wherein, The working end can be removed from the main body.

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