Patent Application
20090093824
The present technology relates to methods for tissue approximation and fastening devices and fasteners for use therewith.
In the case of skin tissue wounds, whether created through a accidental laceration, surgery or disease, healing of the wound occurs best when the layers of the skin are approximated together. In addition to proper side to side positioning (in a horizontal plane), proper wound edge positioning in the vertical plane is required to optimize healing and minimize scarring. The wound edges must be held in the optimal position for a length of time sufficient to allow for healing. When fastening wounds, the layers of the skin that must be aligned include the epidermis and the dermis. The epidermis is the superficial-most layer of the skin and it must be well aligned during wound closure to seal off the wound. However, closure of the epidermis alone may not provide sufficient strength while the wound is healing. The dermis is the deeper layer of the skin and is particularly important with regard to proper wound approximation. The dermis is the strongest layer of the skin and wound closure techniques that incorporate the dermis into the closure provide the most structural integrity.
Currently, skin staplers are often used to close wounds because they are easy to use and save substantial time in the operating room. These staplers use metal clips/staples that are inserted from the superficial skin surface. Despite efficiency and ease of use, the disadvantages of metal staples include: (1) the need to subsequently remove the staples (which can be painful for the patient) and (2) permanent marks on the surface of the skin at the staple insertion points (leading to prominent scarring which resembles a “railroad track”). To avoid these disadvantages of metal staples, surgeons may use a “layered-closure” approach in which stitches are placed in the deeper dermal layer and in the superficial epidermal layer. The deep dermal stitches are resorbable and provide tensile strength that prevents the scar from widening and becoming more prominent and allows for use of finer superficial stitches (or even glue or tape strips) as needed which leave less surface scarring. The superficial sutures may be resorbable or permanent (non-resorbable). If non-resorbable superficial sutures are used, they can be removed early (which minimizes scarring) because the deep dermal sutures remain in place to provide strength while the wound is healing. This layered closure approach is routinely used by plastic surgeons in order to minimize scarring. The key to this layered closure approach is accurate placement of resorbable sutures in the deep dermal layer.
The current method of manually placing deep dermal sutures is tedious and time consuming. In addition, manual suturing eposes healthcare workers to potential needle-stick injuries which could lead to the transmission of infectious diseases (such as hepatitis C). The ideal solution to these wound closure problems would (1) allow for efficient wound closure (especially relative to hand suturing techniques), (2) eliminate the patient discomfort associated staple removal, (3) reduce the scarring associated with traditional metal staples, and (4) reduce the risk of needlestick injuries. These goals would best be achieved by technology that places resorbable fasteners under the skin surface (in the dermal layer) in an automated fashion. Others have attempted to develop this type of resorbable deep dermal fastening system. In particular, Green et al. (U.S. Pat. Nos. 5,292,326, 5,389,102, 5,423,856, 5,489,287, and 5,573,541) designed a dermal stapler that interdigitated the wound edges in an undulating/serpentine configuration. This device then fired straight resorbable pins across the wound edge interdigitations in order to secure the edges of the wound together. This product (referred to as the AutoSuture SQS 20) was not successful for various reasons, including wound-healing problems which resulted from the undulating/interdigitating wound edge configuration. Others have attempted to create an effective dermal fastening device (U.S. Pat. Nos. 6,726,705, 7,112,214, and D0532107). However, the device of the foregoing applications have significant disadvantages including: (1) difficult/awkward method of use, (2) creation of contour irregularities in the skin (visible “dimpling” effect where the fasteners are inserted), (3) inability to bear any significant tension on the wound, (4) extrusion of the fasteners through the superficial skin surface. Some of the reasons for these shortcomings include the fastener geometry and the method of fastener insertion.
Patent Application Publication US 2007/0049969 to Peterson discloses an applicator apparatus that rotatably places non-flexible arcuate fasteners across tissue edges for approximation. Their falcate tissue penetrator “carries” a fastener and pushes the fastener through the tissue to approximate and secure the edges. The cross sectional shape of their falcate tissue penetrator is a right angle. Our drive needle is nothing like that and is instead more like a modification of a traditional suture needle. SHEET 44, FIG. 41: See parts 506a and 506b. These arms in their device serve to position the wound edges externally (i.e. superficial skin surface) which is away from the deep surface where the actual fastener insertion is occurring.
Despite these prior attempts by others, it would be desirable for surgeons and others to provide an effective and automated resorbable dermal closure system.
The present technology describes an effector end capable of driving a fastener between two tissue edges to approximate the tissues in a wound, incision and the like. The effector end can be fitted to any medical fastening device for use in tissue fastening. The effector end comprises: an arcuate needle being moveable from a resting position to an engagement position. The arcuate needle is operable to receive a fastener. The effector end also includes two or more approximator arms each being moveable from a resting position to an engagement position. A top plate and a bottom plate are disposed above the arcuate needle and the two or more approximator arms when the arcuate needle and the two or more approximator arms are in their resting state. The arcuate needle and the two or more approximator arms are disposed between the top plate and the bottom plate when approximating the tissue and inserting the needle through the tissue and releasing the fastener. At the end of the fastening steps the approximator arms and arcuate needle are in an engagement position. The arcuate needle does not penetrate the epidermis of the tissue and releases the leading retention member of the fastener in the deep dermis region of the second tissue approximated.
In a further aspect, a method for approximating or closing the edges of a wound is provided. In some embodiments, the method comprises the steps: (a) approximating a first tissue edge and a second tissue edge, the first and said second tissue edges comprising an epidermal layer, and a dermal layer; (b) driving a fastener through the lower portion of the first tissue dermal layer in an arcuate fashion across the second tissue edge. The fastener comprises a leading retention member and a trailing retention member and a longitudinal member therebetween. During fastening of the tissues the longitudinal member spans across the first and second tissue edges. The leading retention member being placed in the dermal layer of one of the tissues and the trailing retention member being placed in the dermal layer of the other tissue: and
(c) advancing the device to an adjacent position between the tissue edges and repeating steps (a) and (b).
The wound is substantially closed by advancing the device along the wound site and repeating the approximating and fastener insertion steps described above.
The drawings described herein are for illustration purposes only and are not intended to limit the scope of the present technology in any way.
The following description is merely exemplary in nature and is not intended to limit the present technology, application, or uses.
The terminology used herein is for the purpose of describing particular example embodiments only and is not intended to be limiting. As used herein, the singular forms “a”, “an” and “the” may be intended to include the plural forms as well, unless the context clearly indicates otherwise. The terms “comprises,” “comprising,” “including,” and “having,” are inclusive and therefore specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof. The method steps, processes, and operations described herein are not to be construed as necessarily requiring their performance in the particular order discussed or illustrated, unless specifically identified as an order of performance. It is also to be understood that additional or alternative steps may be employed.
When an element or layer is referred to as being “on”, “engaged to”, “connected to” or “coupled to” another element or layer, it may be directly on, engaged, connected or coupled to the other element or layer, or intervening elements or layers may be present. In contrast, when an element is referred to as being “directly on,” “directly engaged to”, “directly connected to” or “directly coupled to” another element or layer, there may be no intervening elements or layers present. Other words used to describe the relationship between elements should be interpreted in a like fashion (e.g., “between” versus “directly between,” “adjacent” versus “directly adjacent,” etc.). As used herein, the term “and/or” includes any and all combinations of one or more of the associated listed items.
Although the terms first, second, third, etc. may be used herein to describe various elements, components, regions, layers and/or sections, these elements, components, regions, layers and/or sections should not be limited by these terms. These terms may be only used to distinguish one element, component, region, layer or section from another region, layer or section. Terms such as “first,” “second,” and other numerical terms when used herein do not imply a sequence or order unless clearly indicated by the context. Thus, a first element, component, region, layer or section discussed below could be termed a second element, component, region, layer or section without departing from the teachings of the example embodiments.
Spatially relative terms, such as “inner,” “outer,” “beneath”, “below”, “lower”, “above”, “upper” “top” and “bottom” and the like, may be used herein for ease of description to describe one element or feature's relationship to another element(s) or feature(s) as illustrated in the figures. Spatially relative terms may be intended to encompass different orientations of the device in use or operation in addition to the orientation depicted in the figures. For example, if the device in the figures is turned over, elements described as “below” or “beneath” other elements or features would then be oriented “above” the other elements or features. Thus, the example term “below” can encompass both an orientation of above and below. The device may be otherwise oriented (rotated 90 degrees or at other orientations) and the spatially relative descriptors used herein interpreted accordingly.
The present technology provides a tissue fastening effector end that can be used in medical fastening devices that enable automated and efficient closure of surgical incisions, wounds and approximation and attachment of surgical devices and materials to tissue. The present technology overcomes the deficiencies of the prior art by enabling approximation and fastener driving steps sequentially and by reversing the drive needle followed by tissue release in a manner that yields superior and secure tissue alignment which provides more favorable results. Moreover, wound alignment in the proper X, Y and Z axes in relation to the wound skin surface is provided using the approximation and fastening device of the present technology.
The present technology also provides a method for precisely inserting fasteners from the underside of the wound surface and into at least a portion of the dermal layers of the skin (without violating the external or superficial skin surface). The effector end generally comprises an effector end for use in a medical fastening device comprising: an arcuate needle being moveable from a resting position to an engagement position, the arcuate needle operable to receive a fastener; two or more approximator arms each being moveable from a resting position to an engagement position; and a top plate and a bottom plate disposed above the arcuate needle and the two or more approximator arms when the arcuate needle and the two or more approximator arms are in said resting state. The arcuate needle and the two or more approximator arms are disposed between the top plate and said bottom plate when in said engagement position.
For ease of illustration, the tissue approximation and fastening system comprising a tissue fastening device 10. The system and fasteners of the present technology will first be described, this will be followed by a description of the methods of using the tissue fastening device to approximate the edges of wounds and for laparoscopic use to approximate tissues to other tissues or to other substrates including prosthetic meshes, scaffolds and other materials.
As illustrated in
In some embodiments, the tissue fastening device 10 can comprise a handle 30, a device body member 20 that is part of handle 30, a trigger 32 and an effector end 12. As shown in
An exemplary embodiment of a tissue fastening device 10 of the present technology is illustrated in
A top plate 22 and a bottom plate 24 of effector end 12 are aligned in a parallel fashion. The top and bottom plates 22 and 24 each have a central apex. The angle of each half of a horizontal plane is approximately 5°-45° best illustrated in
The effector end 12 includes components that provide the general fastening mechanism at the site of tissue approximation. Once the tissue fastening device 10 has been placed into position within the tissue wound or incision as illustrated in
Upon compression of the trigger 32 by the operator (a surgeon, surgical assistant, nurse or other medical practitioner) moving the trigger 32 towards the handle 30 initiates the first stage of approximation. The actuator channel pins 94 biases the actuator in a downward movement as the actuator channel pins 94 exerts a force against the actuator channel plateau 130. In response of this downward movement of the actuator 110, the actuator gear rack 126 disposed on the lateral side 124 of the actuator 110 also moves in a downwards direction and rotates the approximator arm gears 70 to cause the gear rack 73 to rotate clockwise and gear rack 72 to rotate counter clockwise. Rotation of the approximator arm gears 70 concomitantly rotates the approximator arm axles 46 and 47 which are mated with their respective gears 70. The rotation of the approximator arm axles 46 and 47 translates into the rotation of their attached approximator arms 48 in a similar clockwise and counterclockwise fashion respectively. The rotation of the approximator arms 48 results in the piercing of the dermal tissue and insertion of the approximator arms into the dermal tissue thereby bringing the two tissue edges into closer contact with the center partition 26 and each other. Although there are at least two approximator arms 48 per approximator arm axle 46 and 47, the approximator arm axle 46 and 47 may comprise 2 or more approximator arms 48 per approximator arm axle. The compression of trigger 32 also induces a movement in a downward direction of the trigger gear rack 92. Since the trigger gear rack 92 is enmeshingly engaged with the arcuate needle gear 80, movement of the trigger gear rack 92 in a downward fashion causes the arcuate needle gear 80 to rotate in a clockwise fashion (when the viewer is looking from distally towards the effector end of the device). The clockwise rotation of the arcuate needle gear 80 translates to the clockwise rotation of the arcuate needle axle 60 which is mated to the rotation of the arcuate needle gear 80 as depicted in
Upon further compression of the trigger 32, the channel pins 94 biases the actuator in a downward movement as the channel pins 92 exert a force against the actuator channel plateau 130 until the actuator cannot travel any further in a downward direction. As a result, the approximator arms 48 connected to approximator arm axles 47 and 46 have fully rotated in their respective direction within the dermis of the tissue. This action generally results in the full approximation of the tissue contained within the tissue insertion site 23. This engagement position is illustrated in
The next stage in the fastening process takes advantage of the fact that the approximator arms 48 are fully approximating the tissue edges and are being held stationary while the next stage of fastening proceeds. In order to continue the movement of the arcuate needle 62 in its arcuate path without over rotating the approximator arms 48, the trigger 32 is further compressed towards the handle 30. The trigger 32 continues to move towards the handle and advantageously compresses against the actuator ensuring that the actuator remains stationary as the actuator channel pins 94 starts to descend down the actuator channel 128. The commencement of this stage is illustrated in
Although the tissue fastening device 10 has been described with reference to
Returning back to
Once the fastener has been inserted, the arcuate needle 62 needs to be de-rotated back out of the two tissue edges 502 and 504. The arcuate needle 62 is retracted along the same path as was used for inserting the leading retention member 230. If the approximator arms 48 were to release the wound edges prior to de-rotation of the drive needle, the smooth path that the drive needle created on its way in would be altered. This alteration in the tissue configuration would make it difficult for the arcuate needle 62 to rotate back out of the wound. In other words, the arcuate needle 62 would bind up on the surrounding tissue. To prevent this problem, the approximator arms 48 keep the wound edges firmly approximated until after the fastener insertion needle has rotated out of the wound. This sequence is accomplished by reversing the triggering mechanism described above. Essentially, as the trigger 32 is being released and commences to move away from the handle 30, the movement of the trigger away from the handle causes the trigger gear rack 92 to start moving up and this motion induces the enmeshingly engaged arcuate gear rack 82 to rotate the arcuate needle gear 80 and cause the arcuate needle to retract to its resting position. This rotation of the arcuate needle gear 80 then rotates the arcuate needle axle and causes the arcuate needle 62 to rotate in an arcuate fashion, exactly the opposite form the way in which the arcuate needle 62 was originally inserted. As the trigger 32 continues to move to its original resting position, the actuator channel pins 94 begin to move up along the actuator channel 128. When the trigger 32 is approximately released half-way, the actuator channel pins 94 begin biasing the actuator to move upwards towards the actuator head barrier 144. Once the actuator 110 starts to move upwards, the actuator gear racks 126 also begin to move in an upward direction. When the actuator gear rack 126 disposed on the lateral side 124 of the actuator 110 move in an upwards direction, the enmeshingly engaged approximator arm gears 70 connected to approximator arm axles 46 and 47 rotate away from an engaged position towards a resting position. Rotation of the approximator arm gears 70 concomitantly rotates the approximator arm axles 46 and 47 which are mated with their respective gears 70. The rotation of the approximator arm axles 46 and 47 translates into the rotation of their attached approximator arms 48 in a similar fashion The rotation of the approximator arms 48 on approximator arm axle 46 and the opposite rotation of the approximator arms 48 on the approximator arm axle 47, results in the retraction of the approximator arms 48 from the dermal tissue back towards its resting position as shown in
Hence, the present device advantageously retracts the arcuate needle 62 first and approximator arms 48 second in a coordinated fashion that minimizes the displacement of the inserted fastener and prevents binding of the arcuate needle 62 on the surrounding tissue upon retraction of the arcuate needle 62 and approximator arms 48.
In some embodiments, the fastener 64 can be modified to adjust to the form of the arcuate needle 62 and arcuate needle fastener slot 246. With reference to
In some embodiments, a variation on the arcuate needle 62 is illustrated in
In some embodiments, a tissue fastening device 10 is illustrated in
As illustrated in
The longitudinal member 222 can also include one or more barbs along the surface as shown in
In some embodiments, the leading and trailing retention members 230 and 220 respectively can be shaped to be the same or be different. In some embodiments, the second end of the leading retention member 240 can include a cone (as shown in
In some embodiments, the arcuate needle 62 shown in
In some embodiments, the fasteners of the present technology can be non-resorbable, or absorbable. In some embodiments, the fastener 64 includes a generally bioabsorbable polymer selected to maintain effective retention strength for a period of at least 5 to 21 days within the body, and optimally at least 14 days before eventually being fully absorbed within the human body. General criteria for the materials to be selected in the manufacturing of the fasteners of the present technology can include biocompatibility and fastener deformability. The fasteners 64 of the present technology are easily deformable when the leading and transverse members are displaced along a vertical axis (i.e. bending of the longitudinal member to either side of its long axis). However, the fasteners 64 are very resistant to any stretching or elastic deformation when the leading and transverse members are displaced along a horizontal axis (i.e. high tensile strength along the long axis of the longitudinal member). Such selection of H-fasteners described herein offer several advantages over the preexisting field, for example, the curved solid fasteners of the preexisting field rely on resistance to tissue stretching when the curved fasteners are placed either horizontally or vertically in relation to the surface of the skin. Such resistance is mediated by the bending strength of the fastener. In contrast, the fasteners 64 used in the present technology are very flexible (in a direction lateral to the long axis of the longitudinal member but not along the long axis of the longitudinal member), have a lower profile, and can accommodate any arcuate needle design. The fasteners 64 are not bulky and have a lower profile and therefore require less force to extend them across the tissue edges. In addition, the lower profile of the longitudinal member 222 of the fasteners 64 translates to less material being present in the wound edge interface, which will result in less inflammatory response. The fasteners 64 of the present technology rely on tensile strength to keep the tissue edges approximated and fastened even days and weeks after placement. The fasteners of the present technology offer the convenience of staples but function more like suture material than staples or solid arcuate fasteners of the prior art.
Examples of the non-absorbable biocompatible materials which can be used in the manufacture of the fasteners 64 include polypropylene, nylon, polyethylene, polyester polyolefin and the like and equivalents thereof. Exemplary absorbable and resorbable biocompatible polymeric materials that can be used to manufacture the H-fasteners of the present technology can include polydioxanone, polygalactic acid, polylactic acid, polycaprolactone, lactide/glycolide copolymer, a poly(dl-lactide), a poly(l-lactide), a polyglycolide, a poly(dioxanone), a poly(glycolide-co-trimethylene carbonate), a poly(l-lactide-co-glycolide), a poly(dl-lactide-co-glycolide), a poly(l-lactide-co-di-lactide), a poly(glycolide-co-trimethylene carbonate-co-dioxanone), collagen, and elastin, either individually, in blends or as copolymers as well as equivalents thereof. The polymers can be mixed with tissue growth enhancing materials such as calcium ceramics; such as calcium phosphates, calcium sulfates, calcium phosphate apatites; antibiotics, e.g. aminoglycosides, ansamycins, carbacephem, carbapenems, cephalosporins, glycopeptides, macrolides, monobactams, penicillins, polypeptides, quinolones, sulfonamides, and tetracyclines; anti-inflammatory agents, e.g. non-steroidal anti-inflammatory drugs, naproxen, ibuprofen, aspirin; collagen and tissue growth factors involved in wound healing, for example, TGF-β, PDGF, VEGF, EGF, fibronectin and mixtures thereof and the like. In some embodiments, the H-fasteners of the present technology can be manufactured from other conventional types of biocompatible materials including metals such as stainless steel, spring steel and nickel-titanium alloys (e.g., Nitinol), ceramics, composites, and the like and equivalents thereof.
Methods of Using the Tissue Approximation System
The tissue fastening device 10 can be utilized by surgeons, physicians, nurses, surgical assistants and other medical personnel to accomplish a variety of skin closures including intentional, surgical incisions as well as accidental lacerations. Generally, a first step in effectuating wound closure with tissue fastening device 10 is to position the effector end 12 in the wound as illustrated in
As illustrated in
As illustrated in
In some embodiments, a laparoscopic device is provided wherein fasteners 64 can be used to anchor materials such as prosthetic mesh or other substrates and materials to tissue during operations such as laparoscopic hernia repair (rather than using the fasteners 64 to close surgical wounds). The fastening device 10 disclosed in the present technology can also be used in any type of anchoring/fastening application during laparoscopic surgery (i.e. not just for fastening mesh to tissue). This technology could also be used in any situation where access to the fastening site is difficult (i.e. not just during laparoscopic operations).
In some embodiments in accordance with the present technology, a laparoscopic fastening device is provided that comprises an elongate tubular member having a distal potion and a proximal portion. A distal portion of the laparoscopic device can be inserted into a wound or laparoscopic port site wherein the distal portion has a drive/fastener means as illustrated for the tissue fastening device 10. The laparoscopic tissue approximation device has a proximal portion that can be connected to an actuator comprising a triggering mechanism as described above for the tissue approximation system. The triggering mechanism can be operably coupled to the drive/fastener mechanism; and the fastening of one or more fasteners. The triggering means upon actuation engages said drive/fastener mechanism; and the drive/fastener means can comprise a rotatable slotted arcuate needle 62 and one or more approximator arms 48 operable rotationally as described above for the tissue fastening device 10.
Various laparoscopic fastening methods exist, including variations of the traditional H-fastener such as the I-Clip™ Tissue Fixation System by Autosuture (Covidien Ltd., Mansfield, Mass., USA) The current methods of H-fastener insertion involve linear penetration of the tissue followed by advancement of the H-fastener. This linear insertion is sub-optimal because of the following reasons: 1. The linear insertion is performed in a “blind fashion” (i.e. the needle is inserted linearly into the adjacent tissues, creating the potential for damage of critical structures). 2. The linear fastener insertion is performed at the tip of the device, in line with the longitudinal axis of the body of the device. This configuration makes it difficult to position the device for fastener insertion in certain situations. 3. The leading end of the fastener is inserted in a “buried” fashion in the adjacent/underlying tissue. That method makes fastener insertion (i.e. secure anchoring) more difficult.
In some embodiments, the method of rotatably inserting the fasteners via an arcuate needle 62 solves the problems described herein in the following ways. Arcuate insertion of the fastener results in an almost tangential “bite” of the underlying tissue which provides the needed support without requiring deep penetration. The result is a diminished potential for damage of the underlying tissue structures. The arcuate insertion of the fastener allows the effector end 12 of the tissue fastening device 10 to be positioned against the site where fastening is required, which makes fastener application easier. In some embodiments, where laparoscopic use of a tissue fastener is required, both the leading and trailing ends of the fasteners lie on the same side of the mesh while the longitudinal portion of the fastener crosses the mesh to lie in an essentially horizontal course in the adjacent tissue. This configuration results in improved fastener holding strength and reliable insertion because the leading end of the fastener does not lie in a “buried” position.
This application claims the benefit of U.S. Provisional Application No. 60/997,736 filed on Oct. 4, 2007. The entire disclosure of the above application is incorporated herein by reference.
| Number | Date | Country | |
|---|---|---|---|
| 60997736 | Oct 2007 | US |
