Patent Application
20070055294
The present invention relates to surgical instruments used when closing an incision or wound in body tissue and to instruments in general that are used for the purpose of sewing fabric or suturing patients. In particular, the present invention relates to an instrument that magnetically assists the positioning of a needle when released from the grip of a user or surgeon. The device provides a means to pre-position the needle for easy grasping subsequent to disengagement from a tool or fingers. Likely applications include conventional surgery, minimally invasive surgical procedures such as laparoscopic and other developing image guided endoscopic techniques that are performed within the body in areas of limited access, and general sewing using a curved needle such as in upholstery or carpeting.
Surgery has been long in development and the relentless advance in techniques and equipment has led to the miracles of our more modern era. Every day thousands of surgeries are performed in the United States alone. Some are emergencies, others elective, but all require the suturing or sewing together of the wounded organs in both repair and closing procedures.
Today, most surgeries are performed by opening up the body cavity through the various layers of muscle and fat. Subsequent to the repair, removal or replacement of the involved organ, this suturing process is an elemental component of the surgical process. Suturing of the wound is a fundamental skill learned early in the career of a surgeon and each develops his own style. Throughout the suturing procedure the surgeon has to release and re-grasp the needle a number of times. Each time the needle is re-grasped, the surgeon must ensure that the needle is positioned and oriented correctly within the jaws of the instrument holding the needle so that the needle can then be re-inserted into and through the tissue to make another stitch.
Accordingly, the surgeon must first determine the position and orientation of the needle in the jaws. This is difficult because the surgeon's view of the needle and the instrument is not always unobstructed, and in the case of non-invasive surgery is via a two-dimensional image transmitted by the camera. Next, the needle may need to be adjusted within the jaws, as necessary, which is difficult because the jaws only open and close.
Further, the surgeon must ensure that the needle is not dropped since the needle is likely to be difficult to locate within the cavity in the person or in the transmitted image. Once located, the re-acquisition of a dropped needle, particularly with the suturing instrument, is a challenge. Often a special instrument and another hand to manipulate the instrument are required, especially in non-invasive surgical applications.
Naturally, failure to locate the needle could pose fatal consequences for the patient and litigation for the physicians. The adequate control of the needle(s) during and after the suturing process noted above is a key issue addressed during surgery. Recently since the 1990's new medical endoscopic procedures have been developed which do not require the body part being repaired to be completely opened and these procedures are being performed with ever increasing frequency.
These minimally invasive medical procedures are defined as those that are carried out by entering the body through the skin or through a body cavity or anatomical opening with the smallest damage possible to these structures. Generally, these procedures also involve the extensive use of remote imaging devices that are utilized by both the primary and attending physicians and staff to coordinate their efforts during the operation. Because the entry wounds that are used to access the surgery area are very small, the cutting and separating of various tissue layers to expose intra-abdominal organs is not required.
One of the most useful benefits from this type of procedure is that patient rehabilitation periods are considerably shorter in comparison with traditional fully invasive surgery. The importance of needle control in this two-dimensional operating environment cannot be over emphasized with regard to both loss and prevention of inadvertent “sticking.”
As has been previously indicated, all of these procedures, be they invasive or non-invasive, require a plurality of incisions which will require later repair through suturing. In practical surgical applications, any simplification of the basic suturing process, especially that of control of the needle, is desirable and is beneficial to the recovery of the patient. Today's cost conscious environment also places a priority on minimal implementation costs in materials and re-training. Much effort has been spent toward achieving those goals and as shall be seen related prior art has examples that propose in several ways to resolve some or all of these issues. None is perfectly satisfactory with regard to results.
U.S. Pat. No 5,201,744 (Jones) describes a method and device for suturing using a rod with a needle holder. The primary goal of this device is providing a surgical knot tying tool that is useful in surgery procedures for centering a suture knot on a wound in body tissue of limited accessibility and that can be manipulated from an area of accessibility outside the body. The device contains and controls the suture thread and needle and is used in conjunction with other tools to position the suture knots during surgery. While in one embodiment the device employs a magnetized component to retain the needle internally, implementation of the methodology requires the presence of another function specific surgical tool in the surgeon's inventory.
U.S. Pat. No. 5,417,701 (Holmes) defines a suturing instrument that uses a magnet to properly position, orient and hold a suturing needle within its jaws. The magnet is embedded in one of the jaws and when the jaws are near the needle, the magnet attracts the needle to it, causing the needle to move to a predetermined position on the jaw containing the magnet. Numerous mechanical internal components grasp, release and position the needle as required. Specialty needles may also be indicated as noted in the proposal. Beyond the additional expense likely to result from manufacture of this contraption, general use would require that another, procedure-specific tool, be readily available to the operator and tool specific training is implied.
U.S. Pat. No. 5,431,670 (Holmes) depicts a suturing instrument that uses an electromagnet to position, orient and hold a needle at the end of an elongated barrel, thereby eliminating the mechanical jaws which are otherwise required. As indicated in the description, this elegant solution to the simple problem of controlling the positioning of the suture needle involves switches, power supplies, electromagnets, multiple controls, special needle holders, and potentially, specialty suture needles with special coatings. Only the largest hospitals could likely afford to provide this complex device which as described would require significant additional training of the physician, calibration and maintenance procedures.
U.S. Pat. Application No. 2003/0105474 (Bonutti) portrays a mechanism and method intended to provide the capability of passing a medical implement through tissue with magnetic or electromagnetic forces. Several versions are envisioned some with multiple magnets and multiple required instruments. Though this invention eliminates the need to accurately position a separate standard suture needle, it does necessitate development of new as yet to be developed surgical technique and requires a specialized device in addition to those that might normally be found in, say, third world countries.
With respect to the above description, before explaining at least one preferred embodiment of the invention in detail, it is to be understood that the invention is not limited in its application to the details of construction and to the arrangement of the components or steps set forth in the following description or illustrated in the drawings. The various apparatus and methods of the invention are capable of other embodiments and of being practiced and carried out in various ways which will be obvious to those skilled in the art once they review this disclosure. Also, it is to be understood that the phraseology and terminology employed herein are for the purpose of description and should not be regarded as limiting.
As such, those skilled in the art will appreciate that the conception upon which this disclosure is based may readily be utilized as a basis for designing of other devices, methods and systems for carrying out the several purposes of the present disclosed device. It is important, therefore, that the objects and claims be regarded as including such equivalent construction and methodology insofar as they do not depart from the spirit and scope of the present invention.
Further objectives of this invention will be brought out in the following part of the specification, wherein detailed description is for the purpose of fully disclosing the invention without placing limitations thereon.
There exists in medicine today a need for a simple method and mechanism to effect control and positioning of the suture needle during surgery that is inexpensive, does not require specialized equipment other than that which might be present in a nominally equipped hospital surgery, and does not imply additional training and specialization on the part of the physician.
It is thus the object of the present invention to provide a simple to use, inexpensive device that is readily incorporated into a previously learned surgical procedure such as suturing and that provides substantially improved control of the surgical needle during and after the process. An additional object of the present invention is to provide enhanced protection against needle sticks. These and other objects are accomplished by a method and apparatus for controlling and manipulating the position of surgical needles during surgery through magnetic interaction with the invented device.
The disclosed device employs a permanent magnet sufficiently powerful for the task at hand, which can be employed in various possible configurations and materials. In a particularly preferred embodiment of the device a toroid or “donut” shaped magnet imbedded within or below the stand or base would be used to attract the suture needle into a final resting in an upright position upon the top surface of the device. Using the magnetic field from the magnet, a needle dropped onto the top surface moves in such a way that the needle starts upright with the needle tip on the top surface and exposing the proximal end upright at preferably approximately one third (⅓) or more of the total length.
In all embodiments of the device disclosed herein and anticipated, a magnet or means to generate a magnetic field is positioned on a base to thereby generate a magnetic field through the top surface of the base. This magnetic field is sufficient to hold a needle deposited on the top surface upright when released from a tool or the hand in cases of a curved or ramped top surface. In the case of a flat top surface the magnetic field is sufficient to urge a needle deposited on the top surface upward and hold it in an upright position.
In physics, a magnetic field is an entity produced by moving electric charges (electric currents) that exerts a force on other moving charges. The quantum-mechanical spin of a particle produces magnetic fields and is acted on by them as though it were a current; this accounts for the fields produced by “permanent” ferro magnets.
A magnetic field is a vector which associates with every point in space, a vector that may vary in time. The direction of the field is the equilibrium direction of a compass needle or other ferrous member placed in the field. In mathematics a vector field is a construction in vector calculus which associates a vector to every point in a Euclidean space. Vector fields are often used in physics to model, for example, the speed and direction of a moving fluid throughout space, or the strength and direction of some force, such as the magnetic or gravitational force, as it changes from point to point. Like the electric field, the magnetic field can be defined by the force it produces. The magnetic force exerted on a moving charge takes the form of a vector product or force vector.
Fmagnetic=q{right arrow over (v)}×{right arrow over (B)}=qvB sin θ
The right hand rule is a useful mnemonic for visualizing the direction of a magnetic force as given by the Lorentz force law that calculates the force vector of a moving charge in the equation:
As calculated, the force vector is thus perpendicular to both the velocity v of the charge q and the magnetic field B. The direction of the force is more easily understood as what is conventionally termed in physics as the “right hand rule”. The force relationship above is in the form of a vector product or the force vector of a given magnetic field.
In addition to exerting a force vector which imparts force and direction on ferrous material placed in the field, the magnetic field can can cause a piece of magnetic material placed in the field, to rotate. Consequently, an object which possesses a magnetic dipole moment such as a compass needle or in the device herein, a curved sewing needle, will rotate in response to a magnetic field. Such rotation is ascribed to the effect to a magnetic torque. For a given field the strength of the magnetic torque on an object placed therein is taken as a measure of the magnetic moment of the object.
Using these principles to explain the function of the device herein which was discovered by experimentation and numerous configurations, a curved sewing needle placed in a generally upright position on top of a deport surface of a base can be held in a position substantially normal to the top surface of the base by the force vector of the magnetic field properly generated above the surface. The magnetic field generated above the top surface of the base must be such that the force vector of the field generally aligns with the plane through both ends and the center section of a curved needle and thus exerts the force to hold it upright and normal to the top surface.
Further, it has been found through experimentation that if the needle is magnetized itself, the resulting magnetic torque will cause a curved needle to actually rotate to an upright position if placed on the surface at an angle or parallel to the surface. Still further, it has been found that the needle may be provided magnetized, or once left in the magnetic field generated above the top surface of the base for a short period of time, it will become magnitzed to provide this utility to the user who may simply drop the needle on the top surface at any angle and have it rotate to a vertical position.
The device features an upper surface which may be planar or may have the curvature of the suture needle or may be dimensioned with a depression to mechanically aid positioning and rotation of the deposited needle. The surface of the device may also be coated for sterility or manufactured of an inert biologic or magnetic material or some permutation of all. Preferably the resting surface for the deposited needle is made of material that has a low coefficient of friction to allow the needle to move freely.
The device itself and/or the landing area for the needle is not limited in shape to a circle but can be rectangular, oval, curved or angled or any shape that suits the purpose and anticipated area of use. In the more useful embodiments of the device, the final resting place of the needle on the top surface of the device is preceded by a “landing area” into which the needle is dropped when released from the needle-holding tool or the fingers. The falling needle is then drawn to the magnetic field above the top surface traveling in a pre-defined path. This path has a gradual curve or slant and a needle guide on the sides of the path. The combination of the magnetic field, the force vector and or magnetic torque, act to influence the needle along with the congruence of the gradually curved or slanted path and the embedded needle guide. The end result is that a needle deposited generally upright in the simplest embodiment of the device will be held substantially normal to the top surface of the base. In modes of the device with one or both of magnetized needles or shaped top surfaces to mechanically aid positioning of the needle the result is the needle assuming an upright position no matter at what angle it lands on the top surface of the base. Even more dimensioning of the top surface to move the needle as it is acted on by gravity and the magnetic field will cause it to stand on its distal end next to the tip which leaves the proximal end upright and exposed to be easily re-grasped by the needle holder in a “loading position.” If configured correctly, the top surface of the base acting in concert with the magnetic field will position the needle such that at least ⅓ of the needle is elevated above the top surface for gripping by a tool or the hand.
An object of this invention is to provide a device which pre-positions a needle for stitching and suturing to be easily grasped by a tool or fingers.
Another object of this invention is to provide such a needle positioning device which employs a magnetic force to coax a needle deposited thereon to maintain a generally upright position for grasping.
An additional object of this invention is the provision of such a needle positioning device which will coax a deposited needle upright when deposited on a planar top surface using magnetic force or a combination of magnetic force and mechanical urging.
A still further object of this invention is the provision of such a needle positioning device which additionally dimensions the shape of the top surface to combine with and aid the magnetic field coaxing a needle deposited thereon to an upright position.
Yet another object of this invention is the provision of such a needle positioning device that is sufficiently flexible to be rolled or otherwise compressed through a small opening and subsequently returned to full size for use.
Another object of this invention is the provision of such a flexible needle positioner that may be used in surgery inside of the patient's body and inserted and removed through a very small opening.
These together with other objects and advantages which become subsequently apparent reside in the details of the construction and operation as more fully hereinafter described and claimed, reference being had to the accompanying drawings forming a part thereof, wherein like numerals refer to like parts throughout.
a-d depict top and cross sectional views of possible embodiments of the device 10.
a are views of a flexible embodiment of the device which may be rolled or folded for insertion into a cavity.
Referring now to the drawings,
Such magnetic fields are produced by electric currents, which can be macroscopic currents in wires, or microscopic currents associated with electrons in atomic orbits. The magnetic field is defined in terms of force on moving charge in the Lorentz force law. Magnetic field sources are essentially dipolar in nature, having a north and south magnetic pole.
As noted, in the device 10 herein disclosed the magnets 16 or other means to generate the magnetic field 30 are shaped and/or positioned as a means to generate the magnetic field 30 sufficient to, and with the proper field lines, to yield a magnetic force vector sufficient to hold the needle 12 upright and in equilibrium between the lines of the field in relation to the top surface 15 of the base 18. Preferably of course, the magnetic field 30 generated and force and torque vectors therefrom will also rotate a non-upright needle 12 which is magnetized or becomes magnetized by the magnetic field and is deposited on the top surface 15 to the upright position, much like the needle of a rotationally engaged compass is rotated to north by force and direction of the lines in the earth's magnetic field. While this can be done on a planar version of the base 18, dimensioning the top surface 15 of the base 18 with a shaped portion such as a ramp or a concave top surface or other mechanical means to urge the needle upright works especially well.
In addition to the magnetic field 30, additional means to coax the needle 12 to rotate upright when dropped on the top surface 15 may be provided by forming a shaped portion of the top surface 15 by adjusting the dimensional and shape characteristics. To that end, the top surface 15 can be shaped in bowl or inverted hemispherical shape such as shown in
a is a top view of another dimensioning of the top surface 15 of the base 18 wherein the top surface 15 has been dimensioned to an oval shaped cavity. A plurality of magnets 16 are positioned to generate the lines forming the magnetic field 30 and are engaged to the base 18 along the correct axis to urge and hold the needle upright and preferably substantially perpendicular to the top surface 15.
b is a top view of another configuration of the top surface 15 of the device 10 in which top surface 15 is dimensioned into the base 18 in the form of a rhombic shaped cavity. Means to generate the magnetic field 30 is provided by a plurality of magnets 16 which are positioned to generate the magnetic field 30 lines along the correct axis and at the proper force to both urge and hold the needle upright and in relation to the top surface 15 thereby allowing easy deposit on the top surface 15 and re-grasping.
Also shown in
a depicts a foldable or rollable embodiment of the device 10 wherein the base 18 is formed of flexible material as is the magnet 16. Any embodiment of the device 10 is capable of folding if the base 18 is made flexible and the magnet 16 is either flexible or sufficiently sized to allow folding or rolling of the base 18. In the case of a flexible magnet 16, such are used widely on novelty items mounted on refrigerators and for signage. The base 18 is depicted in a shape similar to that of a contact lens and provides a hemispherical or curved shaped top surface 15 when the base is unrolled. This configuration of the device 10 is especially well adapted for use inside of a closed area such as inside the body of a patient during endoscopic surgery.
In use in such a procedure, the base 18 would be rolled up and guided through an incision in the body to the inside of the body. Generally, a temporary cavity is formed in the body of the patient by the injection of carbon dioxide gas into the body to distend surrounding tissues and form a cavity of higher pressure. The device 10 would deposited in the formed cavity through an incision such as shown in
In
Finally, it is envisioned that the device 10 in all embodiments and modes herein described may be widely used in surgery where a sterile environment is required. As such, the device 10 including a base 18 with the appropriate magnetic field and top surface 15 can be packaged in a sterile kit along with a curved needle 12 which is magnetized or non-magnetized as the use may require. In such a packaged kit, the user would tear open the sterile packaging and remove the base 18 and needle 12 and thereafter suture the patient using the appropriate method. In such a method, the needle 12 with appropriate thread or suturing material engaged would be gripped by a tool or the fingers for a stitch and then deposited on the top surface 15 where it would remain upright or be tilted upright in the aforementioned fashions. Thereafter the tool would be re-gripped by the fingers or a tool and the process would repeat. Of course the base 18 with the appropriate top surface 15 and magnetic field thereabove could be used with a separate needle 12; however, a sterile kit would be most convenient and allow for a throw away device 10.
Although the invention has been described with respect to particular embodiments thereof, it should be realized that various changes and modifications may be made therein without departing from the spirit and scope of the invention. While the invention as shown in the drawings and described in detail herein discloses arrangements of elements of particular construction and configuration for illustrating preferred embodiments of structure and method of operation of the present invention for rendering a needle upright on a surface using a magnetic field, it is to be understood, however, that elements of different construction and configuration and other arrangements thereof other than those illustrated and described may be employed in accordance with the spirit of this invention. Any and all such changes, alternations and modifications as would occur to those skilled in the art are considered to be within the scope of this invention as broadly defined in the appended claims.
Further, the purpose of the attached abstract is to enable the U.S. Patent and Trademark Office and the public generally, and especially the scientists, engineers and practitioners in the art who are not familiar with patent or legal terms or phraseology to determine quickly from a cursory inspection the nature and essence of the technical disclosure of the application. The abstract is neither intended to define the invention of the application, which is measured by the claims, nor is it intended to be limiting as to the scope of the invention in any way.
