GB2450411A

GB2450411A - A rotating surgical cutting device

Info

Publication number: GB2450411A
Application number: GB0811066A
Authority: GB
Inventors: Peter W Bolton
Original assignee: Individual
Current assignee: Individual
Priority date: 2007-06-21
Filing date: 2008-06-17
Publication date: 2008-12-24
Also published as: GB0811066D0; GB0711981D0

Abstract

A surgical device 201, for removing material from a passage in a human or animal body, comprises a shaft 205 and a cutting head 203 with at least one cutting edge 213. The cutting head 203 has a main body portion 209 and a flange 211 supporting the cutting edge 213. The main body 209 of the cutting head 203 is cylindrical in shape and slightly tapered toward a closed first end. A second end is attached to a flexible shaft 205, formed from a spring, which is fitted with an attachment portion 207. This is insertable into the chuck of a surgical drill (not shown). In use, the cutting edge 213 cuts in the direction of rotation. A detachable funnel device (701, figure 7) may be mounted on the shaft to collect any blood or debris during the cutting procedure.

Description

SURGICAL INSTRUMENT

Field of the Invention

The present invention relates to a surgical device configured to remove material from a passage in a human or animal body, the surgical device comprising a shaft and a cutting head and the cutting head comprises at least one cutting edge. Particularly but not exclusively, this disclosure is applicable to the removal of granulated and/or infected tissue from an ano fistula tract.

io Background to the Invention

A fistula is an abnormal passage between two internal organs within a human or animal body or from an internal organ to the surface of the body.

An ano fistula is an abnormal passage from the mucosa muscle region within the anal passage through the lavata muscle to the surface of the skin on the buttocks. Ano fistulas affect one in a thousand people on a global scale and can be very painful affliction which can seriously impact a person's quality of life.

The known method of treating an ano fistula is to use a curette to remove the granulated and/or infected tissue present in the tract of the ano fistula. With reference to figure 1 herein, there is shown a plan view of a known curette in the prior art. Curette 101 comprises a handle portion 103 attached to a first end of a shaft 105. At a second end of the shaft 105 there is disposed a spoon-like *** portion 107 comprising an aperture 109. * **

*****. 25 * *** During use in the treatment of ano fistulas, the curette 101 is inserted into the fistula tract. The user of the curette 101 grips the handle portion 103 and applies pressure thereto, to force the spoon-like portion 107 against a wall of the **** fistula tract. The user must then move the curette 101 backwards and forwards * * * : 30 in order to scrape the spoon-like portion 107 against the walls of the fistula tract ****** * effecting removal of the granulated and/or infected tissue.

P1902.spec A disadvantage of employing a curette to remove the granulated and/or infected tissue in the tract of an ano fistula is that the user of the curette cannot see which portions of the fistula tract have been successfully curetted and which require further curetting and so are unable to determine whether all of the granulated and/or infected tissue has been removed. Furthermore, the user of the curette must work in a 3600 circumference within, on average, a 50 mm tract which further adds to the difficulty in assessing whether all of the tissue has been removed from the fistula tract. If there is even a small amount of the granulated and/or infected tissue remaining in the fistula tract after curetting then the granulated and/or infected tissue will build up once again. Therefore, use of a curette to remove tissue from a fistula tract inevitably leads to recurrence of the symptoms of an ano fistula within around twelve months.

Once the area of the fistula tract has been curetted, a seton is permanently fitted within the fistula tract. A seton is a surgical thread which is passed from one of the fistula tract to the other and is regularly moved in order to keep the tract clear and allow the tract to be drained of any pus which builds up.

Therefore, the patient must wear a dressing at all times which is uncomfortable and can cause embarrassment.

The method of curetting an ano fistula and inserting a seton does not cure the patient of the ano fistula and recurrence is inevitable. A patient who is living with a seton fixed in the fistula tract cannot enjoy a high quality of life and will often experience copious amounts of pain due to the build up of pus in the fistula * .1 **** 25 tract. Furthermore, recurrence is expensive as the patient would need to visit a hospital three to four times a year to be treated, costing the NHS a lot of money. **..

Therefore, the inventor has sought to provide a surgical instrument which aims to remove all granulated and/or infected tissue in a fistula tract, thereby ***S * S S eradicating this condition which will consequentially restore the patient to *.**.S * * normality and enhance their quality of life.

P1 902.spec

Summary of the Invention

An object of the present invention is to provide an improved surgical device that successfully removes all granulated and/or infected tissue from a fistula tract such that the problems associated with fistulas will not recur.

The invention achieves the object for an improved surgical device of the above type by providing a surgical device configured to remove material from a passage in a human or animal body, said surgical device comprising a shaft and a cutting head, said cutting head comprising at least one cutting edge, said surgical device characterised in that said cutting head is configured to rotate and said at least one cutting edge is configured to cut in the direction of rotation of said cutting head.

The rotational motion of the cutting head enables the cutting edge to contact the full circumference of the fistula tract in order to remove the granulated and/or infected tissue to reveal the healthy tissue below. Furthermore, the shaft of the surgical device enables the user of the device to pull the cutting head through the fistula tract thereby efficiently removing all of the granulated and/or infected tissue therein. In this way, recurrence of the problems associated with fistulas is prevented, dispensing with the need for repetitive treatment and so reducing the cost to the NHS.

Preferably the cutting edge is in the form of at least one tooth that projects * *.

25 from a surface of said head. Furthermore, the cutting edge is preferably curved.

The inventors have found that it is optimum to have a curved cutting edge in the form of at least one tooth as this is the most effective shape of cutting edge at ripping the tissue requiring removal from the fistula tract, exposing the healthy tissue below. * *** * * *

***S.. * *

P1902.spec The tooth may comprise a body in the form of a helix. In this embodiment it is preferable for the tooth to extend helically substantially in the linear direction defined by the longitudinal axis of said shaft.

Preferably the at least one cutting edge is provided for culling when said culling head rotates in a clockwise direction.

The combination of the helically shaped teeth comprising curved cutting edges and the clockwise motion of the cutting head enables the cutting edge to positively contact the walls of the fistula tract. Therefore, the cutting edge will efficiently remove all granulated and/or infected tissue present in the fistula tract.

In a most preferred embodiment of the present invention the cutting edge is in the form of four teeth and these are positioned equidistant from adjacent teeth.

Four is the optimum number of teeth disposed on the cutting head of the surgical device given the required shape and size of the teeth. This is because they efficiently rip and disperse tissue away from the cutting edges so the surgical device can operate effectively without the threat of clogging of the teeth.

Preferably the cutting head is disposed at a first end of said shaft.

In a preferred embodiment of the present invention the culling edge is * ** configured to extend substantially in the direction defined by the longitudinal axis of said shaft. **..

::::. Preferably the cutting head comprises a substantially cylindrically shaped main body portion with said at least one culling edge being located substantially towards the point of attachment of said shaft. * * 30 *

*S. s** * * The cutting head may have a diameter of from 3 to 7 millimetres. It is not possible to produce a cutting head having a diameter of less than 3 millimetres as P1902.spec it would be impossible to dispose four cutting teeth of the optimum size and shape on the circumference of the head. The preferred diameters of the cutting head are 3 millimetres and 5 millimetres.

Preferably the substantially cylindrically shaped main body portion is tapered.

Preferably the cutting head further comprises a flange and the cutting edge is configured to extend from said flange.

It is advantageous for the substantially cylindrically shaped main body portion to be tapered in order to reduce the resistance of the trailing body portion of the cutting head as the surgical device moves through the fistula tract.

Furthermore, it is advantageous for the cutting head to further comprise a flange from which the cutting edge extends as this flange will have a greater diameter than the main body portion of the cutting head and so resistance of the trailing main body portion will be effectively reduced to zero.

In a preferred embodiment the cutting edge, the flange and the substantially cylindrically shaped main body portion of the cutting head are formed integrally.

Preferably the shaft has a diameter of from 2 to 3 millimetres, and a length of from 70 to 90 millimetres. It is further preferable that the shaft is capable of adapting to the fit the contours of said passage in a human or animal body. * *.

*.. 25 The length of the shaft is important as the shaft is formed of a flexible :.:::. material in order for it to stretch along the fistula tract. Therefore, a shaft with a longer length than the above range would be prone to sagging and during use, may begin to whip around causing damage the patient's body.

** 30

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P1902.spec The shaft may comprise a multicore cable or alternatively, the shaft may comprise a spring as these materials retain the strength of the shaft whilst allowing it to stretch and form to the contours of the fistula tract.

In a prefered embodiment of the present invention the surgical device further comprises an attachment portion disposed at a second end of said shaft.

This attachment portion may be configured to enable attachment of said surgical device to a rotary device, which rotates the surgical device at a speed of from 15000 to 19000 revolutions per minute.

The range of speed of rotation is important to the operation of the surgical device as the inventors have found that a rotary device effecting rotation at a speed outside of this range does not enable the surgical device to efficiently remove the granulated and/or infected tissue from the fistula tract.

Preferably the surgical device is made of hardened surgical stainless steel.

In particular the surgical device is made from 416 surgical stainless steel.

This type of surgical stainless steel has a hardening quality which is ideal for the cutting teeth of the present invention as it will provide optimum cutting of the patent's tissue.

The surgical device may further comprise a detachable funnel device formed from a plastics material, It is advantageous for the surgical device to be * ** *.. 25 fitted with a detachable funnel device, prior to the cutting head exiting the *S..

passage of the human or animal body, in order to collect the blood and/or debris :.:::. ejected from the passage. This prevents a messy climax to the procedure.

I *..

I

The surgical device may be configured for single use.

*IlS.I * * Preferably the surgical device is configured to remove granulated tissue from a fistula tract. In the most preferred embodiment of the present invention, P1902.spec the surgical device is configured to remove granulated tissue from an ano fistula tract.

According to a second aspect of the present invention, there is provided a method for the treatment a fistula comprising the steps of: removing granulated tissue from the fistula tract using the surgical device of the present invention; applying a stitch to a first end portion of said fistula tract; injecting acellular porcine collagen into the fistula tract; and applying a stitch to a second end portion of said fistula tract.

The combination of use of the surgical device of the present invention to remove granulated tissue from a fistula tract and then injecting the tract with acellular porcine collagen provides a permanent cure to the problems suffered by the patient as a result of fistulas. The acelluar porcine collagen enables the tissue in the fistula tract to rapidly heal and so prevent any further infection.

Preferably the acellular porcine collagen is combined with a harvested sample of the recipient's DNA prior to its injection into said fistula tract to prevent rejection of the collagen by the recipients body and aid rapid healing. * ** * * * *. 25 **..

The surgical device may be attached to a rotary device effecting rotation of : ** the surgical device at a speed of from 15000 to 19000 revolutions per minutes. **.*

S ***

Preferably the surgical device is pulled through the tract of said fistula as it *:::: 30 is revolved by said rotary device in order to ensure the cutting head of the device * * contacts the whole area of the fistula tract.

P1 902.spec The method may also comprises a further step of attaching a funnel portion to said shaft adjacent to the second end portion of the tract of the fistula immediately prior to the emergence of said cutting edge from said fistula tract.

According to a further aspect of the present invention there is provided a reamer configured to remove material from a passage in a human or animal body, said reamer comprising a shaft and a cutting head, said cutting head comprising at least one cutting edge, said reamer characterised in that said cutting head is configured to rotate and said at least one cutting edge is configured to cut in the direction of rotation of said culling head.

Brief Description of the Drawincis

For a better understanding of the invention and to show how the same may be carried into effect, there will now be described by way of example only, specific embodiments, methods and processes according to the present invention with reference to the accompanying drawings in which: Figure 1 shows a prior art curette used to remove material from a passage in a human or animal body; Figure 2 shows a plan view of the surgical device configured to remove material from a passage in a human or animal body in accordance with a first * ** *... 25 embodiment of the invention; * * **..

:.:::. Figure 3 shows a plan view of a surgical device configured to remove *. material from a passage in a human or animal body in accordance with a second *:. embodiment to the present invention; 30 ****** * S P1902.spec Figure 4 shows a plan view of a surgical device configured to remove material from a passage in a human or animal body in accordance with a third embodiment of the present invention; Figure 5 shows the cutting head of the surgical device of figure 2; Figure 6 shows the cutting head of the surgical device of figure 4; Figure 7 shows a detachable funnel device in accordance with a further embodiment of the present invention; and Figure 8 shows a surgical device in accordance with one embodiment of the present invention in use.

Detailed Description

There will now be described by way of example a specific mode contemplated by the inventors. In the following description numerous specific details are set forth in order to provide a thorough understanding. It will be apparent however, to one skilled in the art, that the present invention may be practiced without limitation to these specific details. In other instances, well known methods and structures have not been described in detail so as not to

unnecessarily obscure the description.

With reference to figure 2 herein, there is provided a surgical device 201 * *.

configured to remove material from a passage in a human or animal body in * * **** accordance with a first embodiment of the present invention. The surgical device :.:. 201 comprises a cutting head 203, a shaft 205 and an attachment portion 207.

Cutting head 203 has a main body portion 209, a flange 211 and a cutting edge 213. *S.. * * *

**.*.S * The main body portion 209 of the cutting head 203 of the surgical device 201 is substantially cylindrical and is slightly tapered, being closed at a first end of P1902.spec the cutting head 203. Flange 211 is disposed at a second end of the main body portion 209 of the cutting head 203 with the cutting edge 213 extending therefrom.

Cutting edge 213 comprises four teeth (two of which are shown) which are disposed around the circumference of the flange 211 of the cutting head 203.

Cutting head 203 is disposed at a first end of the shaft 205 and is positioned such that the first closed end of the main body portion 209 of the cutting head 203, is at a position furthest from the shaft 205. Shaft 205 projects into the internal area of the cutting head 203 and is fixed therein by a suitable fixing means, for example a screw fix.

Attachment point 207 is disposed at a second end of the shaft 205.

Attachment portion 207 is bullet-shaped and has a smaller diameter of the cutting head 203. Attachment portion 207 comprises an aperture 215 disposed at the end of the attachment device 207 furthest from the shaft 205.

The main body 209, flange 211 and cutting edge 213 of the cutting head 203 are formed integrally from 416 surgical stainless steel. The flange 211 of the cutting head 203 has a diameter of 5 mm. Shaft 205 is formed from a spring having a diameter of around 2 mm and a length of 80 mm. The spring is also made of 416 surgical stainless steel. Furthermore, attachment device 207 is formed from 416 surgical stainless steel. * *.

**. 25 When in use, the aperture 215 of the attachment portion 207 is threaded :*:::. with a seton. The seton and surgical device 201 are then pulled through a fistula * tract via the opening located on the internal surface of the human or animal body and out of the opening of the fistula tract located on the surface of the skin of the **S. * * *

animal or human. Shaft 215 stretches and forms itself to the contours of the *S***.

* fistula tract such that the cutting head 203 is located at the opening of the fistula tract on the internal opening within the human or animal body and the attachment P1902.spec portion 207 is located at the external opening of the fistula tract. The seton is removed from the aperture 215 and the attachment portion 207 is then inserted into the mounting portion of a surgical drill (not shown) and is secured in place by insertion of a chuck through the aperture 215 of the attachment device 207. The surgical device 201 is then rotated by the surgical drill at a speed of around 15,000 to 19,000 revolutions per minute in a clockwise direction. Therefore, the cutting edge 213 of the cutting head 203 positively contacts the material to be removed from the fistula tract.

Figure 3 herein shows a surgical device 301 configured to remove material from a passage in a human or animal body in accordance with a second embodiment of the present invention. Surgical device 301 comprises a cutting head 303, a shaft 305 and a attachment portion 307. Cutting head 303 comprises a main body portion 309, a flange 311 and cutting edge 313.

is Attachment portion 317 comprises an aperture 315.

The arrangement and use of the components of the surgical device 301, the cutting head 303 and the attachment portion 307 in figure 3 are identical to the arrangement and use as described for figure 2. Furthermore, the materials used to form the different components of the surgical device 301 are identical to those employed in relation to the surgical device 201 of figure 2. However, the diameter of the flange 311 of the cutting head 303 is 4 mm.

With reference to figure 4 herein, there is shown a surgical device 401 * ** *,.. 25 configured to remove material from a passage in a human or animal body in accordance with a third embodiment of the present invention. Surgical device :.:::. 401 comprises a culling head 403, a shaft 405 and an attachment portion 407.

S *.S

S

* Cutting head 403 comprises a main body portion 409, and a cutting edge 411. The main body portion 409 of the cutting head 403 is bullet-shaped being *S**.* * closed at a first end portion. Cutting edge 411 extends from the circumference of P1902.spec an open portion of the main body portion 409 located at a second end portion of the main body portion 409.

Cutting head 403 is disposed at a first end of the shaft 405 such that the closed portion of the main body 409 of the cutting head 403 is furthest from the shaft 405. Attachment portion 407 is located at a second end of the shaft 405.

Attachment portion 407 is also bullet-shaped and comprises an aperture 413 located at the closed end of the attachment device 407 furthest from the shaft 405. Aperture 413 allows attachment of the surgical device 401 to a seton in order to insert the surgical device 401 into a fistula tract for use. Furthermore, when the attachment portion 407 of the surgical device 401 is inserted into the mounting portion of a surgical drill (not shown) a chuck may be passed through the aperture 413 of the attachment portion 407 in order to secure the surgical is device 401 in the surgical drill. The surgical drill rotates the surgical device 401 in a clockwise direction at a speed of 15,000 to 19,000 revolutions per minute in order for the cutting edge 411 of the cutting head 403 to positively contact the material which requires removal within the passage of the human or animal body.

The main body 409 and cutting edge 411 of the cutting head 403 are formed integrally from 416 surgical stainless steel. The shaft 405 of the surgical instrument 401 is formed from a multi-core cable such as Boden spring cable having a diameter of 1 mm. This multi-core cable is formed from hardened * *. surgical stainless steel. The attachment portion 407 is also formed from 416 surgical stainless steel. The diameter of the cutting head 403 is 3 mm.

This embodiment of the present invention does not comprise a flange portion due to the reduced size of the cutting head 403. * * S

Surgical devices 201, 301 and 401 as described above are cofigured for Se....

* single use such that they are disposed after the first use.

P1902.spec With reference to figure 5 herein there is shown an enlarged side view of the cutting head 203 of the surgical device 201 in accordance with the first embodiment of the present invention.

Cutting head 203 comprises a main body portion 209, a flange 211 and a cutting edge 213.

The main body 209 is cylindrical having a closed portion 401 at a first end thereof. The flange 611 is disposed at a second end of the cylindrical main body portion 209. The diameter of the cylindrical main body portion 209 is less than 5mm, which is the diameter of the flange 211 of the cutting head 203.

Cutting edge 213 comprises four teeth 403, 405 and 407 (one of which is not shown as it is hidden by the shaft 205) which extend from and are equally spaced around the circumference of the flange 211 of the cutting head 203. The cutting edge 213 is provided in the form of a curve 409, 411 and 413 disposed upon the uppermost surface of the teeth 403, 405 and 407. Teeth 403, 405 and 407 comprise a body in the form of a helix which extends helically from the flange 211 substantially in the linear direction defined by the longitudinal axis of the shaft 205.

Shaft 205 extends into the main body portion 209 of the cutting head 203 and is secured therein. * *b ** . * **

The curved cutting edges 409, 411 and 413 of teeth 403, 405 and 409 S...

extend in a clockwise direction from the flange 211, therefore when the surgical device is rotated in a clockwise direction upon attachment to a surgical drill, the *j. curved cutting edges 409, 411, 413 are the first portion of the device to contact the walls of the fistula tract, tearing and removing the granulated and/or infected tissue in order to expose healthy tissue. Furthermore, the shape of the teeth * prevent the device clogging during use as they efficiently rip and disperse tissue P1902.spec away from the cuthng edge 213 so that it can continue cutting the tissue effectively.

The flange 211 of the cutting head 203 reduces the resistance of the trailing main body portion 209 to a minimum as it is dragged through the fistula tract. This is because, only the flange 211 and the cutting edge 213 are indirect contact with the wall of the fistula tract and so the surgical device travels through the fistula tract experiencing the least possible resistance to its motion.

The arrangement for a surgical instrument having a 4mm cutting head is identical to that shown for the 5mm cutting head 203 described with reference to figure 5.

With reference to figure 6 herein there is shown an enlarged side view of the cutting head 403 of the third embodiment of the present invention. Cutting head 403 comprises a main body portion 409 and a cutting edge 411.

Main body portion 409 is of a bullet-shape having a closed portion 601 at a first end thereof. Cutting edge 401 is disposed at and extends from a second open end 603 of the bullet-shaped main body portion 409.

As in figure 5, the cutting edge 411 comprises four teeth 605, 607, 609 and 611. Teeth 605, 607, 609 and 611 extend from and are equally spaced . around the circumference of the second end portion 603. Each tooth has a * S. curved cutting edge 613, 615, 617 and 619 disposed upon the uppermost surface of the teeth 605, 607, 609 and 611. Teeth 605, 607, 609 and 611 :.:::. comprise a body in the form of a helix and extend helically from the second end . portion 603 of the main body portion 409 of the cutting head 403, substantially in a linear direction defined by the longitudinal axis of the shaft 405. *S.. * * 30

*....: * * Shaft 405 extends into the main body portion 409 of the cutting head 403 and is secured therein.

P1902.spec As in the previous figure, the curved cutting edges 613, 615, 617 and 619 of the teeth 605, 607, 609 and 611 extend in a clockwise direction from the second end portion 603 of the main body portion 409 such that when the surgical device is rotated in a clockwise direction the curved cutting edges 613, 615, 617 and 619 positively contact the walls of a fistula tract ripping and dispersing the granulated and/or infected tissue which requires removal.

The diameter of the cutting edge 403 illustrated in figure 6 is 3mm. Due to the size of this cutting head 403 it is not possible to form a flange at the second portion 603 of the main body portion 409. However, as this cutting head will not be required to cut as much tissue away as would be required by a cutting head having a larger diameter, it will not be as effected by resistance to the motion of the surgical device within the fistula tract.

Figure 7 illustrates a detachable funnel device 701 in accordance with one embodiment of the present invention. The detachable funnel device 701 comprises a main body portion 703 having a first open end section 705 and a second open end section 707.

The main body portion 703 of the detachable funnel devices 701 is tapered such that the circumference of first open end section 705 is much greater than that of the second end section 707.

The detachable funnel device 701 is illustrated in use, wherein it is mounted on a shaft 709 of a surgical instrument of the present invention. The *:*:* shaft 709 passes through the first open end portion 705 of the detachable funnel device 701 through the main body portion 703 and out of the second open end * ** portion 707. ***

* The detachable funnel device 701 is mounted onto the shaft 709 of a *:::: surgical device according to the present invention towards the end of the cutting P1902.spec procedure, when the cutting head of the surgical device is about to exit the fistula tract. In order to mount the attachable funnel device 701 onto the shaft 709 of the surgical device, the attachment portion of the surgical device is removed from the rotary device such as a surgical drill. The attachment portion is then fed through the first open end section 705 of the detachable funnel device 701 and out of the second open end. section 707. The detachable funnel device701 is then moved towards the fistula opening on the surface of the skin of the patient in order to collect any blood and/or debris emerging from the fistula tract as the cutting head makes its exit from the fistula tract. This detachable funnel portion 701 thereby collects all the blood and/or debris accumulated during the cutting procedure and prevents it being sprayed across the operating room when the cutting head of the surgical device makes its exit from the fistula tract.

The detachable funnel device 701 is formed of a disposable plastics material.

With reference to figure 8 herein there is shown a surgical device 801 of the present invention in use removing granulated and/or infected tissue from the fistula tract of an ano fistula. Surgical device 801 comprises a cutting head 803 a shaft 805 and an attachment portion 807.

The cutting head 803 comprises a cylindrical main body portion 809 having a first closed end portion and a flange 811 disposed at a second end thereof. Flange 811 has four cutting teeth extending helically therefrom having curved cutting edges disposed on the uppermost region of the teeth.

Cutting head 803 is disposed at a first end of the shaft 805 of the surgical *..... device 801, which is attached at a second end to the attachment portion 807.

* *, Shaft 805 comprises a spring which stretches and forms itself through the fistula tract 813 such that the cutting head 803 is held at one end of the fistula tract 801 * and the attachment portion 813 remains at the opposite end of the fistula tract **** * S * S. S * *.*. P1902.spec * In this example, the fistula tract 813 has formed within the lavata muscle 815 extending from the mucosa muscle region 817 within the anal passage 819 to the surface of the skin of the buttocks 821. The cutting head 803 of the surgical device is located adjacent to the mucosa muscle region 817 of the anal passage 819 at the opening of the fistula tract 813. The attachment portion 817 is located adjacent to the surface of the skin on the buttocks 821.

In order to treat an ano fistula of the type illustrated in figure 8 the surgeon must first identify the site of the fistula and assess the diameter thereof. A surgical device is selected having a cutting head with a larger diameter than that of the fistula tract in order to ensure all the granulated and/or infected tissue is removed from the fistula tract 813. This is to prevent recurrence of the ano fistula as any granulated and/or infected tissue left behind after the procedure will build up once again and cause problems from the patient.

A seton is attached to the attachment portion 807 of the surgical device 801 via the aperture (not shown). The seton is then pushed through the fistula tract 813 from the mucosa muscle region 817 of the anal passage 819 and out of the lavata muscle region on the surface of the skin of the buttocks 821. As the seton is pulled through the fistula tract 813, the surgical device 801 is carried with it. The shaft 815 of the surgical device 801 stretches in order to form itself to the contours of the fistula tract 813.

The attachment portion 807 is then attached to a surgical drill which is set at a speed of around 15,000 to 19,000 revolutions per minute. The surgical drill * ** is then turned on and rotates the surgical device 801 in a clockwise direction such ** that the cutting edge of the teeth of the cutting head 803 rip into the tissue * ** surrounding the ano fistula tract 813. The user of the surgical drill slowly pulls the surgical device 801 through the fistula tract 813 such that all of the granulated * and/or infected tissue is removed from the walls of the fistula tract 813, exposing *:::: healthy tissue of the lavata muscle 815.

P1902.spec Optionally, towards the end of the culling process and immediately prior to the cutting head 803 making its exit from the fistula tract 813, the detachable funnel device (as described in figure 7) may be attached to the shaft 805 of the surgical instrument 801 via the attachment portion 807 in order to collect all of the blood and/or debris which may be ejected at this time.

The fistula tract is then flushed to remove any residual blood and/or debris present in the tract. A stitch is applied to the mucosa muscle region 817 of the anal passage 819 and the fistula tract 813 is injected with acellular porcine collegan, for example Permacol surgical implant, which is previously combined with a harvested sample of the patient's DNA. The acellular porcine collegan is injected into the fistula tract 813 until it starts to flow out of the opening on the surface of the skin of the buttocks 821. A stitch is then applied to the lavata region of the ano fistula.

The site of the ano fistula 813 heals within around 2 to 3 weeks and will not reccur as a result of all of the granulated and/or infected tissue being successfully removed by the surgical device 801 of the present invention.

The above method for use of the surgical instrument has been described in relation to anal fistula. However, the surgical instrument of the present invention is suitable for use on any fistulas which occur between an easily accessible internal organ of a human or animal body and the surface of the skin of the human or animal. * ** * * S * 55 55* * S **** * 5. * S * S..

S *.* * * S S. *

P1902.spec

Claims

Claims: 1. A surgical device configured to remove material from a

passage in a human or animal body, said surgical device comprising a shaft and a cutting head, said cutting head comprising at least one cutting edge, said surgical device characterised in that said cutting head is configured to rotate and said at least one cutting edge is configured to cut in the direction of rotation of said culling head.
2. A surgical device according to claim 1 wherein said culling edge is in the form of at least one tooth that projects form a surface of said head.
3. A surgical device according to claim 1 or claim 2 wherein said cutting edge is curved.
4. A surgical device according to claim 2 or claim 3 wherein said tooth comprises a body in the form of a helix.
5. A surgical device according to claim 4 wherein said tooth extends helically substantially in the linear direction defined by the longitudinal axis of said shaft.
6. A surgical device according to claim 4 or claim 5 wherein said at least one cutting edge is provided for cutting when said culling head rotates in a clockwise direction. * *** * S **.*

* *.
7. A surgical device according to any one of claims 2 to 6 wherein said 0: 30 cutting edge is in the form of four teeth.
S.. S... * SS *5 S

P1902.spec 8. A surgical device according to claim 7 wherein said four teeth are positioned equidistant from adjacent teeth.
9. A surgical device according to any one of the preceding claims wherein said cutting head is disposed at a first end of said shaft.
10. A surgical device according to any one of the preceding claims wherein said cutting edge is configured to extend substantially in the direction defined by the longitudinal axis of said shaft.
II. A surgical device according to any one of the preceding claims wherein said cutting head comprises a substantially cylindrically shaped main body portion with said at least one cutting edge being located substantially towards the point of attachment of said shaft.
12. A surgical device according to any one of the preceding claims wherein said cutting head has a diameter of from 3 to 7 millimetres.
13. A surgical device according to claim 11 wherein said substantially cylindrically shaped main body portion is tapered.
14. A surgical device according to any one of the preceding claims wherein said cutting head further comprises a flange.
15. A surgical device according to claim 14 wherein said cutting edge is configured to extend from said flange. * ** * S * * S. * SS*
16. A surgical device according to claim 14 wherein said cutting edge, * *. said flange and said substantially cylindrically shaped main body portion of said cutting head are formed integrally. *

I sIll

II 5. *

P1902.spec
17. A surgical device according to any one of the preceding claims wherein said shaft has a diameter of from 2 to 3 millimetres.
18. A surgical device according to any of the preceding claims wherein said shaft has a length of from 70 to 90 millimetres.
19. A surgical device according to any one of the preceding claims wherein said shaft is capable of adapting to the fit the contours of said passage in a human or animal body.
20. A surgical device according to any of the preceding claims wherein said shaft comprises a multicore cable.
21. A surgical device according to any one of claims I to 19 wherein said shaft comprises a spring.
22. A surgical device according to any one of the preceding claims wherein said surgical device further comprises an attachment portion disposed at a second end of said shaft.
23. A surgical device according to claim 22 wherein said attachment portion is configured to enable attachment of said surgical device to a rotary device.
24. A surgical device according to claim 23 wherein said rotary device rotates said surgical device at a speed of from 15000 to 19000 revolutions per *:*::* minute. * *** * * *..*

* **
25. A surgical device according to any one of the preceding claims wherein said surgical device is made of hardened surgical stainless steel. *** * * * ** *

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26. A surgical device according to any one of the preceding claims wherein said surgical device is made from 416 surgical stainless steel.
27. A surgical device according to wherein said surgical device further comprises a detachable funnel device.
28. A surgical device according to claim 27 wherein said detachable funnel device is formed from a plastics material.
29. A surgical device according to any one of the preceding claims wherein said surgical device is configured for single use.
30. A surgical device according to any one of the preceding claims wherein said surgical device is configured to remove granulated tissue from a fistula tract.
31. A surgical device according to any one of the preceding claims wherein said surgical device is configured to remove granulated tissue from an ano fistula tract.
32. A method for the treatment a fistula comprising the steps of: removing granulated tissue from the fistula tract using the surgical device as claimed in claims 1 to 31; applying a stitch to a first end portion of said fistula tract; * *S * * * injecting acellular porcine collagen into the fistula tract; and * *** " 30 applying a stitch to a second end portion of said fistula tract. *** * * * S ** .

P1902.spec
33. A method for the treatment of a fistula according to claim 32 wherein said acellular porcine collagen is combined with a harvested sample of the recipient's DNA prior to its injection into said fistula tract.
34. A method for the treatment of a fistula according to claim 32 or claim 33 wherein said surgical device is attached to a rotary device.
35. A method for the treatment of a fistula according to claim 34 wherein said rotary device rotates said surgical device at a speed of from 15000 to 19000 revolutions per minutes.
36. A method for the treatment of a fistula according to claim 34 or claim 35 wherein said surgical device is pulled through the tract of said fistula as it is revolved by said rotary device.
37. A method for the treatment of a fistula according to any one of claims 32 to 36 wherein said method comprises a further step of attaching a funnel portion to said shaft adjacent to the second end portion of the tract of the fistula immediately prior to the emergence of said cuthng edge from said fistula tract.
38. A reamer configured to remove material from a passage in a human or animal body, said reamer comprising a shaft and a cutting head, said cutting head comprising at least one cutting edge, said reamer characterised in that said cutting head is configured to rotate and said at least one cutting edge is configured to cut in the direction of rotation * *** of said cutting head. * ** * * * **** * 30

I * .II * * * ** I

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