HK1079678B - System for moving and stretching plastic tissue - Google Patents

Description

System for moving and stretching plastic tissue

Technical Field

The present invention relates generally to movement and stretching of plastic tissue in humans and animals, and more particularly to a system for moving and stretching plastic tissue with dynamic forces.

Background

The present application claims priority from provisional application serial No. 60/202,739, filed 5/10/2000, entitled "wound closure system and method", and provisional application serial No. 60/249,766, filed 2000/11/17, entitled "wound closure system and method".

When the tension is released, the elastic tissue returns to a minimally elastic or relaxed state. In this relaxed state, the tissue cells have a spherical shape, the cell walls are thick and strong, the cell surface tension is minimal and in equilibrium. The cells will remain relaxed in this minimally elastic state, exhibiting behavior similar to that of an inelastic material. The force required to stretch the cell in this state is typically close to the force that breaks or severs the intercellular bonds, causing local damage or tearing. Soft tissue in this minimally elastic state provides minimal surface coverage and has maximum resistance to stretching. It is generally believed that a mild constant force below the maximum force threshold applied to the tissue in combination with sufficient hydration will restore the skin to its original elastic state over a period of time. In addition, this force can be applied to the tissue to stretch it beyond the point of equilibrium (normal elastic range) to the maximum elastic range and create the thinnest possible structure to cover the maximum surface area. If the intercellular pressure in the tissue does not exceed the point at which the intercellular bonds are damaged, the tissue remains in the maximum elastic state of healthy tissue and normal biological processes will generate additional cells to restore normal skin thickness and tension, hereinafter referred to as biological creep.

Plastic tissues, such as skin and muscle, have certain viscous and elastic rheological properties and thus viscoelastic properties. Certain plastic structures are capable of increasing surface area over time, which is referred to as "creep". Mechanical creep refers to the elongation of the skin over time under constant load, while biological creep refers to the creation of new tissue due to long-term tensile forces. Constant and sustained forces applied to body tissue such as skin or muscle may result in both mechanical and biological creep. By re-stretching the skin or soft tissue cells, mechanical creep restores the tension that was originally present but was lost at the incision or wound in the skin, thereby increasing skin coverage. Biological creep occurs more slowly and requires the generation of new tissue. Tissue augmentation has long been part of orthopaedic techniques and has traditionally been achieved with balloon-type tissue expanders that are embedded under the skin and inflated and augmented from the outside for a period of time, creating an expanded pocket on the skin for breast reconstruction procedures, such as after radical mastectomy, and for stretching healthy tissue into a flap for soft tissue closure prior to orthopaedic surgery.

Wound treatment, including the treatment and care of large skin defects and severely constricted incisions, is an increasingly important area in today's medical field. There are many types of wounds and conditions that require treatment, including but not limited to: diabetic ulcers and other chronic ulcers; venous stasis ulcers; decubitus or decubitus ulcers; burns; trauma-post-traumatic injury, such as after joint loss, after debridement, skin gangrene, after colectomy, crush wounds with ischemic necrosis; collagen diseases including rheumatoid arthritis; vasculitis (lesions and ulcers caused by arterial insufficiency); amputation; cutting fascia; abdominal surgery; after sternotomy; necrotizing fasciitis; trauma; wounds exposing external tissue or bone; repairing scars; skin lesions; obesity treatment surgery; blunt abdominal trauma with perforations; pancreatitis; neuropathic ulcers; metabolic syndrome (metabolic syndrome); and other subacute or chronic wounds. The management and care of these defects has been a problem due to the difficulty in closing open wounds.

Metabolic syndrome is a condition in which increased pressure in a confined space compromises circulation and tissue survival in that space. In a closed facial metabolic zone, the increase in interstitial pressure leads to capillary damage and vascular insufficiency in the metabolic zone, reducing blood flow. When distended beyond the elastic capacity of the skin, an encapsulated internal pressure is generated. This condition is often caused by capillary infusion following trauma, inflammation, burns or intense muscle use, etc. As the gap pressure continues to increase in time and extent, soft tissue necrosis eventually results. If left untreated, can result in permanent damage to muscle, nerve and vascular structures, resulting in severe loss of primary function, limbs, and even life. Such permanent injuries lead to amputation prior to intensive treatment.

The therapeutic goal of the metabolic syndrome involves minimizing loss of function by rapidly restoring local blood flow. This can be accomplished by surgical decompression, which is reduced by temporary fasciotomy. In fasciotomy, every possible bounding envelope, including the skin, is incised along the entire length of the metabolic zone. Temporary fasciotomies provide space for tissue expansion, which will create a brief relief in pressure, restore normal vascular function, and minimize tissue death due to restricted circulation. The skin remains open after surgical decompression to prevent it from becoming a bounding envelope for a period of time after the ischemic swelling. This large open incision allows the hyperemic tissue to expand beyond the normal skin limits and return to normal pressure. After a certain time, the fluid is resorbed and the tissue returns to the pre-injury size. In many cases, skin closure is initiated by direct suturing or mesh skin grafting three to five days after surgical decompression. However, the wound edges shrink due to the elasticity of the skin, making closure difficult or impossible. The purpose of closing other wounds and skin defects is similar to that of the closing fasciotomy.

Two common methods of wound and skin defect closure include layered skin grafting (split skin grafting) and gradual closure. Stratified skin grafting involves removing a portion of the skin from a donor site, typically the thigh or thigh, leaving a dermal layer in the donor site for re-epithelialization. In this manner, a viable skin repair patch may be transferred or transplanted to cover the wound area. The graft is typically made in a mesh shape, (including cutting the skin to form a series of longitudinally staggered cuts in staggered rows) which allows the graft to stretch to two or three times the coverage area and also allows drainage of the wound as it heals. Normal biological function of the skin can heal these holes after the graft has been received. This type of mesh graft requires a smaller donor area than conventional non-mesh or full thickness skin grafts. However, these methods do not provide optimal visual cosmetic effect or quality of skin coverage. Other disadvantages of this approach include pain at the donor graft site, the formation of additional damaging wounds, and complications associated with incomplete "removal" of the graft. In addition, skin grafting often requires immobilization of the limbs, which increases the likelihood of limb contracture. In addition, increased handling and delayed detention at the hospital can create additional economic burdens.

Gradual or progressive closure is the second closure method. Such techniques may include sewing a catheter loop to the wound edge and pulling the catheter loop and wound together with large sutures in a manner similar to lacing a shoe. Alternatively, the wound edges may be progressively approximated with sutures or sterile paper tape. This gradual or progressive technique has several advantages: no donor site is needed to obtain the graft, the mobility of the extremities is preserved, and good cosmetic results, more durable skin coverage, optimal protection from full skin thickness, normal skin feel can be achieved.

The prior devices implementing gradual closure have a number of drawbacks. The prior methods and devices use mechanical means, such as screw drives, to draw the wound edges together, which require repeated periodic adjustments because relatively small skin movements largely eliminate the closing force. The widely used prior art closure techniques use relatively inelastic materials such as sutures or surgical tape. Excessive tension may cut the skin or cause necrosis due to concentrated loading of the tissue. Current solutions include suture pillows, suture bridges, the use of staples (staples) as anchors at the wound margins, and the use of ligatures to distribute the load along the wound margins. These solutions rely on static tape or suture material that must be repeatedly readjusted in order to function effectively, and even with such frequent readjustment, it is difficult to maintain an approximately constant tension at all times. The widely used conventional gradual closing method relies on static forces obtained by reducing the fixed distance and does not provide a continuous or dynamic tension.

The current method of reducing open wounds is to use static or non-yielding devices such as sutures or the like which reduce the wound edge spacing and rely on the natural elasticity of the skin to compensate for the movement. One problem with such devices is that when they are at the most effective point and when the skin is at the point of maximum tension, the additional skin tension created by an action such as breathing or walking creates stress points at the location where the mechanical fastener contacts the wound edge, causing tearing and wound edge necrosis. This typically requires that the patient remain motionless during the course of treatment. The existing systems for treating animals do not have to take into account the cosmetic results, since healthy patients usually mask the wound site with fur, but the cosmetic results are a decisive criterion in the measurement of the effectiveness of the system in human use.

One prior device for achieving wound closure uses constant tension with a slight force to draw the wound edges together. Such a device is a Proxiderm^TMThe system comprises a pair of hooks carried by a pair of sliders which are pulled along a path by a pair of springs. This spring mechanism is enclosed in a plastic shell and has four models with different curvatures. The sharp hook used in this system may damage the skin. The constant force used is a specified constant force.

Other closure devices are described in U.S. patent nos. 5,234,462 and 5,649,960 to Pavletic, which disclose the use of elastomeric materials, including rubber bands and other types of compressed and non-compressed materials, to approximate the edges of a wound. One kit disclosed by Pavletic requires adhesive to adhere it to the skin and also requires periodic adjustment to tighten the tie. One of these embodiments employs hooks and elastic loops that must be replaced by smaller elastic loops in order to maintain tension. Another Pavletic embodiment uses a motor power source to provide a tensioning device. The Pavletic patent does not disclose a system that does not require repeated adjustment of the tension, or a system that is self-adjusting.

One currently used device is the secure Closure (Sure-Closure) device, which includes two surgical needles, two U-shaped luxon polycarbonate arms with hooks on the underside, a threaded pull rod and a polycarbonate ruler. The needle is passed along the wound edge with each arm positioned over the needle, piercing the skin with the hook and connecting with the needle. The tie rod is then locked and the tension can be adjusted using the screw.

Existing wound closure methods fail to provide effective closure that restores the original tension of the skin lost across the wound. For example, the Proxiderm^TMThe system had a single tension of 460 grams. In many cases, such as for elderly people or damaged skin, this force is too great and can result in failure to locate, tearing and necrosis. Many existing cumbersome devices limit the mobility of the patient and must also be completely removed for wound covering and cleaning, which can only be used in a relatively limited number of situations due to size limitations. Many also require the surgeon to reinstall after the wound dressing is removed. In summary, the prior art devices cannot be easily used for radial closure of wounds due to their limited ability to pull in a single direction along an overhead beam, thereby limiting them to parallel pulls along the same axisThe use of (1).

It is therefore desirable to provide a system that provides manipulation and control of tissue tension on a living human or animal body, utilizing tension and creep to restore and move plastic tissue. There is also a need for a method and apparatus for moving and stretching plastic tissue that is simple, easy to use, relatively inexpensive, has a very large number of uses, and is capable of automatically adjusting and applying relatively constant tension at a distance and at various angles of intersection in a wound of complex geometry.

Disclosure of Invention

The methods, systems and devices of the present invention can move and stretch any plastic tissue. For example, the present invention is used in the dynamic closure of large and small skin wounds, incisions or lesions associated with various conditions, as well as for stretching healthy skin in preparation for skin grafting or other procedures. The present invention includes the use of an elastomeric driving member, which may be in the form of a strip, tape, ring, sheet, mesh, wire, tube, or other structure that can be stretched over a relatively large distance and produce a relatively uniform contractive force, and a fastener for securing the elastomer to plastic tissue. In the simplest use, closure such as fasciotomy, the invention can be used to restore the contracted skin to its original position.

The invention may also be used to stretch the skin to cover an area where a portion of the original skin is missing, such as may be a local burn, ulcer or contracture, and to stretch the skin prior to skin grafting, skin patches or other plastic surgical procedures. Most skin can be stretched by about 20% depending on age, general health, skin condition, degree of skin hydration, and other factors. Under ideal conditions, the skin can be stretched 60% in a few weeks. In rare cases, a stretch of 100% is also possible. Viscoelastic properties of skin are described in Creep v. stretch of Wilhelmi et al: a Review of the Viscoelastic Properties of Skin, 215 optics of Plastic Surgery 41 (8 months 1998), which is incorporated herein by reference.

By introducing an adjustable gradual but continuous tension, the present invention has many advantages over existing methods for moving and stretching plastic tissue. The system according to the invention can be varied substantially steplessly in tension or closure force and can be used in some other restricted areas where skin closure systems are not suitable, including in the lower part of the breast, at the neck and shoulder junction and other such areas, and can be enlarged or reduced as required, using small anchors for ulcer closure and large anchors for abdominal closure. The thickness and cross section of the elastomeric material can be varied to achieve a nearly infinitely adjustable tension as desired.

The present invention shows several important advantages over prior art systems. Human skin varies greatly in elasticity and thickness depending on age and health. Unhealthy patients, such as oncology patients, often exhibit mixed diseases such as presenting thin, fragile and ischemic skin at the constricted wound created in procedures such as mastectomy, where the constricted incision is further stimulated by radiation therapy, which greatly weakens the skin. According to one embodiment of the present invention, various skin anchoring elements match the skin's bond strength to the movement and stretching forces required to minimize necrosis and scarring. In addition, a wide range of movement and tension forces can be generated by a variety of methods by a variety of elastomers that match the tension forces that occur against traction in multiple planes at different locations. Unlike existing devices such as Proxiderm^TMThe present invention, which does not require elevated cross-members, is therefore capable of providing both linear and radial forces applied at multiple points.

According to one embodiment of the invention, dynamic forces are used to move and stretch plastic tissue, providing and maintaining a maximum safe pulling pressure or force on a wound edge. The pressure is maintained below a pressure level that would cause local damage at the wound edge. In this manner, a controlled constant and sustained tension is generated, achieving maximum mechanical and biological yield to move and stretch plastic tissue, including closure of large areas of constricted skin defects.

Dynamic forces are used to pull the wound edges together for a period of time by using controlled and continuous opposing traction forces. In one embodiment, the dynamic forces generated using an elastomer tied to the wound can allow for rapid disassembly for dressing changes and uninterrupted exposure of the wound bed during routine cleaning. This process can be accomplished quickly when tension adjustment is required, and the elastomer can include a readable indicator. Thus, the caregiver can replace the wound dressing and can easily reapply the force prescribed by the surgeon. Utilizing dynamic forces to move and stretch tissue provides the advantage of continuous resistance to traction while allowing expansion and contraction of the wound site, which greatly increases the patient's mobility and accommodates the patient's respiratory motion. In addition, an increased range of pulling forces beyond the elasticity of the skin itself is provided. For example, the average closure rate that can be achieved during treatment ranges from 1.25 to 1.75 centimeters per day, which is much greater (approximately twice as fast) than that achieved using the static pull-off force method of the prior art. The present invention accelerates the reduction of swelling by providing a controlled radial pressure, which promotes the movement of edema fluid through the cell wall, enabling faster lymphatic system uptake. Thus, when applied to fasciotomies, the device according to the invention accelerates the reduction of swelling. The traditional fasciotomy procedure provides for the release of pressure within the metabolic region, but this release is an irreversible process. The methods and devices of the present invention provide controlled pressure relief that, when applied to fasciotomies, enables controlled pressure resorption within swollen tissue below a threshold level that would compromise circulation. The contraction of the skin is controlled, which reduces the amount of rejoining (healing) required to close the wound after the swelling is reduced and after the metabolic zone pressure is normalized.

Drawings

FIG. 1 is a perspective view illustrating a system according to one embodiment of the present invention.

Fig. 2 is a perspective view showing the system depicted in fig. 1 in the process of being fixedly connected.

Fig. 3 is a perspective view illustrating a system according to another embodiment of the present invention.

Fig. 4 is an enlarged view of one of the holders of the system shown in fig. 1-3.

Fig. 5 is a side view of the holder of fig. 4.

Fig. 6 is a top plan view of the holder of fig. 4.

Fig. 7-9 show a fastener and elastomer of the present invention at successive stages in the elastomer joining process.

Fig. 10-13 are some perspective views of alternative embodiments of a holder according to the present invention.

Fig. 14 is a perspective view of an unstretched elastomer according to the present invention.

Fig. 15 is a perspective view showing the elastomer of fig. 14 attached to a holder and stretched in accordance with the present invention.

Fig. 16 is a perspective view of a wound closure system according to another alternative embodiment of the present invention.

Fig. 17 is a perspective view showing the attachment of a holder according to still another embodiment of the present invention.

FIG. 18 is an example of a tension application table for use with one embodiment of the present invention.

Detailed Description

The methods, systems and devices of the present invention provide a number of components and techniques for moving and stretching plastic tissue. More specifically, the members are anchors and a force applying member, specifically including a resilient member, typically connected between two or more anchors. The methods, systems and devices of the present invention use dynamic resistance forces that are equal to or greater than the elastomeric traction force of the plastic tissue. One system of the present invention comprises: at least one tissue fixation device and at least one resilient member. The tissue fixation device is an element that clamps the tissue using, for example, sutures, staples (staples), barbs or thorns (flukes or strokes), adhesives, including surgical glue, and other suitable methods. In one embodiment, the holder is a staple. In an exemplary embodiment, a plurality of anchors are attached to the tissue near the edges of an open wound. An elastic member engages the anchor providing a force that moves and stretches the tissue. In addition to the anchor and elastomer, the system may include a measurement insertion tool and a surgical staple. The system may be applied to the patient during or after the fasciotomy procedure or any time it is desired to move or stretch the tissue.

Figures 1-3 illustrate a wound closure system according to one embodiment of the present invention. As shown in fig. 4-6, the barbed tissue anchor 20 has a generally flat body 22 and a hook 26, the flat body 22 resting against the skin 24, and as shown in fig. 1-3, an elastomer 28 may be positioned around the hook 26. The hook 26 of the barbed retainer 20 is pierced by an eyelet 30 at the front end, through which eyelet 30 the elastomer 28 may optionally pass. The ears 32 extend from the base 33 into openings 34, the openings 34 being located forward of the clips 36 and slots 38. The ears 32 form a staple platform that serves to further stabilize the anterior portion of the anchor when desired.

The elastomer 28 may be retained by clips 36, as shown in fig. 7-9. The frame 40 surrounds a window 42, and the elastomer 28 may selectively pass through the window 42. The elastomer 28 may be attached to the clip 36 from the eyelet 30 or subcutaneously through the central aperture 34 of the anchor 20. The clips 36 may engage the elastomer 28 when the elastomer 28 is stretched and lock the elastomer 28 in place when one end of the elastomer 28 is relaxed. The clip 36 may also permit the elastomer 28 to slide when the applied load exceeds a safe working tension, the limits of which are defined by the size of the clip, the elastomer size, and the elastomer material hardness. The frame 40 may provide a second fail-safe release by dimensional bending of the frame 40 when a specified force is applied that exceeds the workload limit of the clips 36. The deformation of the frame 40 causes the clip 36 to tilt toward the direction of pulling and releasing of the elastomer 28, thereby releasing at safe operating loads and providing a reliable safe operating margin before any traumatic injury to the barb 44 occurs.

The barbed tissue anchor 20 provides a relatively wide contact area with the skin 24, allowing maximum resistance to pulling forces to be applied while minimizing local tissue damage. The barbed tissue anchor 20 may be mounted to the skin 24 by at least one staple 46 or by sutures 35, which sutures 35 may pass at least partially through one or both sides of the slot 38 and around one or both bases 33, or by surgical skin glue or other adhesive. The staple may be installed using a surgical stapler and the provision of the slot 38 allows access to the staple 46 to facilitate removal of the staple 46. Adjacent to slot 38 is a step 48, which step 48 blocks the movement of staple 46 at the rear end of staple travel path 50 between step 48 and logo 52. The logo 52 may be a half-thickness score that is used for part identification and as a visual target for the surgeon to locate the subsequent staple. The logo 52 may be chemically formed on the body 22 or may be formed thereon in any other suitable manner. The path of travel 50 provides unrestricted movement of the staple 46 for distributed and differential stretching of the skin between the barb 44 and the anchor body 22, which occurs at the portion of the skin directly beneath the anchor body 22. The step 48 limits the rearward movement of the staple 46. Securing the fixator with staples in this manner counteracts upwarp forces at high stress pull points under high loads. The path of travel 50 allows the body 22 of the holder 20 to slide in a direction generally perpendicular to the wound, but holds the holder 20 firmly against the skin 24.

The marker 54 shown in fig. 2 is used to mark the skin 24 prior to attachment of the holder 20. As shown in FIGS. 1 and 2, the barbs or barbs 44, having legs 56 and feet 58, penetrate into and through the epidermis of the skin 24 to firmly secure the barbed tissue fastener 20 in place. Thus, the barbs 44 act as catches, attach to the skin 24 due to their shape and angle, and maintain this attachment under tension. The feet 58 assist in this grappling function, preventing the barbed anchor 20 from backing out of the skin, and provide safety against further entry of the barbs 44 into the tissue when directed pressure is applied to the anchor 20. The barbs 44 can be disengaged from the skin 24 by releasing the tension applied by the elastomer 28 and retracting the barbs 44 at an angle opposite the angle of engagement.

The barb 44 shown in the figures is merely exemplary and may have other cross-sections and longitudinal shapes and it is envisioned that the barb may be bent during installation. For example, one variation of barbs 44 could have wider and longer legs and feet. The barbs 44 may be circular in cross-section rather than square or rectangular. In another embodiment, the anchor also functions as a staple such that the anchor includes barbs that bend and lock against the skin similar to barbs located on a staple. Thus, the fixator has the functions of both the fixator and the staple.

Marker 54 is designed to be mounted on a standard scalpel handle to provide a visual reference for the surgeon to penetrate the skin 24 for insertion of the barbs 44 of the barbed tissue anchor 20. The marker 54 may use surgical ink or form a small indentation mark on the skin that serves as a guide for the surgeon to create a pair of small puncture wounds with an 11-gauge blade or other suitable blade or tool. This allows the barbs 44 of the barbed tissue anchor 20 to be inserted through the epidermis of the skin 24.

In one embodiment of the present invention, as shown in fig. 1-6, each pair of skin fixation devices provides a controllable dynamic stretching or closing force of between about 0 and 1000 grams. In an alternative embodiment, the components of the present invention are scaled down and exert less force, while another embodiment includes a greater proportion of components and therefore exerts greater force. Thus, the barbed tissue fastener 20 and all of the fastener configurations described herein can be made in a variety of sizes. The anchor typically has a body length of about 5 mm to 60 mm and a body width of about 2 mm to 50 mm. The smallest holders for good tissue closure typically have a body width of about 2 mm to 10 mm and a body length of about 5 mm to 15 mm. The body width of a typical fixator for general surgical use is about 10 mm to 25 mm, and the body length is about 20 mm to 30 mm. In one embodiment for treating larger abdominal injuries, the anchor typically has a body width of about 20 mm to 50 mm and a body length of about 25 mm to 60 mm.

Also shown in fig. 1 and 2 is unbarbed tissue anchor 60 having a separate hook 62, which hook 62 may act as a hook around which elastomer 28 is positioned, as well as a clip into which elastomer 28 is gripped. The unbarbed anchor 60 has at least one slot 64 for receiving a staple or suture. The unbarbed anchor 60 may be secured by surgical glue and other adhesives, either alone or in combination. An unbarbed anchor 60 may be used when it must be placed in the vicinity of the anchor or in close proximity to the wound. The term "vicinity" refers to an area within 2 cm of the incision or wound edge and comes from the phrase "vicinity of the surgical field. "unbarbed anchors 60 are most often used on wound margins or incision ends, and are often used in opposing pairs. One advantage of the unbarbed anchor 60 is that no puncture is required for the barbs. Thus, an unbarbed anchor 60 may also be used when less invasive procedures are required.

For example, the methods and devices of the present invention may be used on one or more moving and stretching facial plastic tissues. In one embodiment, smaller unbarbed retainers are used to heal facial lesions. Because no penetrating indicia are required, or the indicia are limited to only those formed by staples, facial lesions can be treated in a less invasive manner. In this embodiment, the reduced size unbarbed anchor may be secured to the skin with adhesive, surgical glue, or other suitable means.

In one embodiment, unbarbed tissue holder 60 is attached to a viscoelastic suture, such as silastic^TMOr sutures made of latex material. Typically, the viscoelastic suture is inserted outside the wound margins and extends across the wound, leaving the skin outside the other margin of the wound. Unbarbed tissue fixation device 60 may be used to grip the suture as it exits the skin, connecting the system to the suture. In this embodiment, the unbarbed tissue holder 60 acts as a grommet, eliminating point loads from the suture exit orifice to reduce the incidence of positioning failure and allowing adjustment of the tension across the wound. Reducing the failure of the positioning also reduces scarring. This combination of viscoelastic sutures and anchors creates a linear plane of tension whereby the skin is moved and stretched, allowing the wound to be reduced across the shortest possible distance without following the contours of the body cavity. This is important in situations such as in severely debilitating patients with contracted abdominal wounds, and in situations where a large cavity remains after removal of the tumor. In another embodiment, such a suture is used with at least one barbed tissue fastener. One example of a suitable suture is disclosed in U.S. patent No. 5,895,413 to Nordstrom, which is incorporated herein by reference in its entirety.

In an alternative embodiment, the system is used with a transfixion suture which is a suture that passes through all layers including: skin, subcutaneous tissue, fascia, muscle, and peritoneum. In this embodiment, the through sutures are secured to a retainer to distribute the load.

As shown in fig. 1-3, the elastomer 28 may be threaded through the eyelet 30 of the hook 26 of the barbed tissue anchor 20, wrapped through the hook 26 of the barbed tissue anchor 20 or wrapped through the breakaway hook 62 of the unbarbed anchor 60, or may be clamped by the clip 36 or breakaway hook 62. As shown in fig. 1, the elastomer 28 may be "tied" through a series of fixation hooks by wrapping through each fixation element hook located on the wound boundary or edge. The elastomer 28 may engage the clip 36 (first through the window 42) or disengage the hook 62 to terminate the tie-through. As shown in fig. 3, the elastomer 28 may be used with a number of pairs of anchors. The ends of the elastomer 28 pass through the eyelets 30 of the hooks 26 of the barbed retainer 20 and then through the windows 42 and clips 36. This approach can allow for control of unbalanced wound tension, which is desirable in situations requiring different closure forces or in situations requiring alternating pulls on the wound. The use of the elastomer 28 with the anchor as described above allows the device to operate in a biaxial plane to treat wounds on curved body surfaces, such as the surface of the foot.

Elastomer 28 may be made of virtually any elastomeric material that may be received for use in the vicinity of an open wound, including, but not limited to, latex or silicone rubber, natural rubber, American standard styrene-butadiene rubber, neoprene, nitrile butyl polysulfide, ethylene polyurethane, or any other suitable material that generates a restoring force when held in an extended state. The elastomer 28 provides a dynamic resistance force that is equal to or greater than the natural elastic drag force of the skin. The elastomers of the present invention may generally be formed into a tubular shape having an outer dimension of about 0.125 inches, although other shapes, sizes, and forces may be suitable in some circumstances. The elastomers of the present invention are generally not endless loops but are in the form of a single strand of one length, sometimes referred to as a "single strand," which may be solid or hollow. In some cases, multiple strands or endless loops or bands may be used. Notably, the elastomer used in the present invention may be secured to a retainer member at almost any point along the elastomer, providing variable tension within the elastic limits of the elastomer.

Fig. 10 illustrates another embodiment of a barbed tissue fastener. This barbed tissue anchor 66 has a hook 68 with an eyelet 70 threaded through the hook 68. The clip 72 extends from the main body 74 and a tail stabilizer 76 extends from the main body 74 in the same plane and carries a keyhole clip 78. The body 74 also has a bayonet hole 80. Fig. 10 shows that one end of the elastomer 28 ends with a clip 72 and is positioned by the eye 70 of the hook 68. The other elastomer end is secured in a keyhole clip 78. The staple 46 is received in the staple hole 80 and assists the barb 82 in positioning the barbed retainer 66. Stabilizing staple 83 is inserted across tail stabilizer 76 to counteract the lifting force under high loads at high stress pull points. Stabilizing staples 83 can allow tail stabilizer 76 to slide in a direction generally perpendicular to the wound, but hold barbed anchors 66 firmly against the skin. The elastomer 28 is locked in the keyhole clip 78 of the barbed retainer 66, which allows the elastomer 28 to wrap around an object or limb and allows one end of the elastomer 28 to be clipped in the clip 72 and the other end of the elastomer 28 to be clipped in the keyhole clip 78. In this manner, radial tension may be provided by a single anchor and one elastomer.

Figure 11 illustrates another alternative embodiment of the barbed tissue fastener of the present invention. This barbed retainer 84 has a generally flat body 86 which rests on the skin. The hook 88 of the barbed tissue anchor 84 is threaded with an eyelet 90 through which the elastomer 28 may be selectively passed, the hook 88 also being split to form a clip 92, the clip 92 being capable of gripping the elastomer 28. The elastomer 28 may pass through the eyelet 90 and be held by the clip 92. This alternative barbed anchor 84 also has barbs 94, each comprising a leg 96 and a foot 98. The optional barbed fasteners 84 may be secured to the skin with at least one staple or suture passing through the slot 100, or surgical skin glue or other adhesive.

Fig. 12 shows yet another embodiment of the fixator of the present invention. The pulling fixture 102 has a generally flat body 104 with alternating slots 106 and holes 108 in the edge. The space of slot 106 and hole 108 accommodates all standard skin staples. A staple may be placed across the narrowed arm 110 through a slot with the protrusions 112 preventing the staple from sliding past the narrowed arm 110. The pulling anchor 102 has barbs 114, including legs 116 and feet 118.

The drag holder 102 also has two clips: a front hook 120 and a rear clip projection 122. The front hook 120 is pierced with an eyelet 124 through which the elastic body 28 can selectively pass, and has a clip 126 that can grip the elastic body 28. The rear clip projections 122 are pierced by rear apertures 128 and split to form clips 130, the resilient bodies 28 being selectively insertable through the rear apertures 128, the clips 130 being adapted to grip the resilient bodies 28. This dual clip design can allow for the use of two rows of fasteners on each wound edge, as one or more elastomers can be secured to the front hook and rear clip. In this embodiment, the pull anchor 102 is located at the edge of the wound, while the other anchor, including one pull anchor or any of the anchors described herein, is located at a greater distance from the wound, thus forming two rows of anchors. This alternative embodiment further distributes the load across the holder. FIG. 13 shows yet another alternative embodiment of a barbed tissue fastener including a clip and a hook with an eyelet therethrough.

Holder 20, and any other holders described and illustrated herein, may be made of metal, plastic, or other suitable material. For example, the holder may be formed by chemically etching a 0.015 inch sheet of 304 stainless steel using a texture mating double-sided photo-chemical resistant etching process to form a suitably shaped holder blank, which is then bent into the final shape. Such holders are formed by unmarked free etching, while the logo and identifier are formed by half etching in a single process. The light-resistant facing is stripped and the holder is finished in abrasive media to provide good flash removal prior to final cleaning and processing.

In one embodiment, the holder is formed of plastic or other suitable material. In another embodiment, the holder is disposable. In another embodiment, the disposable anchor is attached to the skin using a pressure sensitive adhesive with a release backing attached to the bottom surface of the anchor member.

Fig. 14 and 15 show an elastomeric body of the present invention having an integral tension indicating member. A mark 132 on the elastomer 28 is used to indicate tension, the mark 132 may be marked (e.g., with a colorant such as ink, paint, stain, dye or other colorant) on the elastomer, or may be a raised ring or annular indentation or any other suitable structure. In one embodiment, the markers 132 are spaced apart by a distance of one centimeter. In other methods of placing markings on elastomeric body 28, equally spaced markings may be marked on elastomeric body 28 by using a pen or other writing instrument to mark on elastomeric body 28 with reference to a ruler or inserted through a slot in a marking ruler or other device having spaced holes in INCA. The markers 132 are spaced apart a distance L1 when the elastomer is in a resting state. As the elastomer is stretched, the distance between adjacent markings 132 increases to L2. When the appropriate amount of tension to be applied is determined, the distance L2 between the elastics is measured and recorded so as to be accurately reproducible after the system has been dressed for any reason, such as dressing changes. Measuring the difference in distance, L1/L2, allows the surgeon to determine how much tension is now being applied by reference to the earlier determined forces generated by stretching similar elastomers (of the same type and size) the same distance. This information can be written in a table, as shown in fig. 18, which the surgeon can refer to convert the measured distance into the amount of tension.

In yet another embodiment of the invention, as shown in fig. 16, a dynamic wound closure force is applied to the wound by attaching a loop of suture 134 to the wound edge 136 with a small holder or clip 138. By applying force to the suture 134 along the length of the wound, the wound edges 136 are drawn together, as shown in fig. 16. This embodiment is shown in fig. 16 using a medical tape 140, which is described below, but may be accomplished using any of the fastening methods described herein. The application of force is accomplished by connecting sutures 134 to the ends of an arch 142, which arch 142 may be wood, plastic, steel or other suitable material that can be deformed into an arch and straightened to separate arch ends 144 and 146.

The invention can be applied to clinical settings where local anesthetics are used. The surgeon determines in which direction the skin needs to be retracted to assist closure. The wound length is measured to estimate the number of anchors required. The spacing of the appropriate holders will depend on the location and nature of the wound and other factors. For example, a fixator used on a long wound on a person's forearm is placed one every approximately three centimeters. A skin marker is used to mark a line one centimeter from the limits or edges of the wound and then anchors are installed, typically in opposing pairs, generally from the center of the wound. The surgeon may choose to use a tissue fixation device without barbs near the incision. Unbarbed tissue fixation devices may be installed using a single surgical staple for light loads or using multiple staples or sutures for higher loads.

In addition, the surgeon may choose to install barbed tissue fixation devices, which are typically used at distances greater than two centimeters from the incision boundary or edge, and in situations where the pulling force to be applied exceeds the fixation range of one unbarbed tissue fixation device or one of the other fixation devices described above. Barbed tissue fixation devices may be used when they are needed to prevent eversion of the wound edges, which would prevent healing. The marker instrument 54 is used to provide instructional indicia to the surgeon for inserting the barbs 44 of the barbed fastener 20 into the skin 24, the penetrating wound being formed by a suitable blade such as a #11 blade. The barbed tissue fastener 20 is then stapled, sutured, or secured in place with glue. If at least one staple is used for fixation, one staple 46 is installed across the line of travel 50 to allow movement of the anchor 20 and thus prevent the barbs 44 from penetrating the dermal layers of the skin, which may be caused by high back pull loads from off-axis thrust exceeding the back torque force provided by the hypodermis layer. If additional stability is desired in the anterior portion of the barbed tissue anchor 20, a second staple may be installed across the ears 32.

The wound bed may be covered with a wet, dry or other suitable dressing 37 (as shown in fig. 1). One such suitable dressing is Duoderm ®, available from Smith & Nephew company, or Tegaderm ®, available from 3M company. The elastomer 28 may be used in a lacing fashion as shown in fig. 1 or by connecting two opposing anchors with a length of elastomer as shown in fig. 3. Additionally, the length of elastomer may also be wrapped around the body member. The elastomer 28 exerts a relatively constant force over a relatively large distance. The lacing pattern of the elastomer 28 is used when a uniform amount of tension is desired along a shear plane, such as is typically required in a long straight cut. When an irregularly shaped lesion requires varying forces along more than one strike-face, the elastomer segments between opposing anchors are used individually or in multiple simultaneous applications. This is usually the case with Z-plasty, L-flap incisions or an incision that does not lie in a plane through the skin. A single elastomer 28 may also be used to encircle an object or wound to create radial tension. The elastomer 28 may be unclamped or released from the grip multiple times, allowing for easy dressing change, repositioning, and re-stretching.

In one embodiment of the invention for fasciotomy closure, this method of gradual wound closure eliminates the need for subsequent suturing, as the device draws the wound edges together so that the wound closure is as if sutures were present. Eliminating delayed closure can provide treatment in only one surgical procedure.

In another embodiment of the present invention, including any of the anchors described herein, the anchor is mounted on a medical tape, such as a tape backed with a pressure sensitive adhesive, as shown in fig. 17, which in this embodiment is attached to the patient at the wound edge. In another embodiment, the clips are made as a unitary strap retaining structure such that they are sandwiched between two layers of medical strap. Such an integral strap retaining structure may be a structure having a large surface area and having a plurality of through holes such as honeycomb cells, or circles, or other suitable structures.

The system and method for moving and stretching plastic tissue according to the present invention is not limited to the embodiments described herein, but includes various changes and modifications within the scope and spirit of the foregoing description and drawings. For example, the proportions of the components of the invention may vary widely depending on the location and nature of the body tissue in which the invention is used. The structure of the holder may also vary for the same reasons as well as for aesthetic reasons. Although most of the elements of the exemplary embodiments of the fixation devices of the present invention depicted in the drawings are functional, the shape and appearance aspects of these exemplary embodiments are non-functional and decorative.

The materials used to make the components used in the practice of the present invention may be those described above, as well as other materials, including materials that have not yet been developed with suitable strength, elasticity, etc., as will be apparent to those skilled in the art in view of the foregoing. For example, the materials used must generally be sterile or sterilizable and hypoallergenic. The components shown by way of example herein are generally intended to be reusable, but the invention may also be used with disposable components, such as, for example, metal or plastic fasteners supplied in a sterile package, the fasteners optionally having a pressure sensitive adhesive on one surface of the fastener covered by a release film for protecting the adhesive prior to use of the fastener.

Claims (17)

1. A system for stretching plastic tissue, comprising:

(a) at least one elastomer (28); and

(b) at least one holder (20);

wherein the elastomer (28) is removably secured to the anchor (20), the anchor (20) being adapted to be attached to tissue, wherein the system provides adjustable tension, characterized in that the anchor (20) further comprises a clip having two diverging arms (36) separated by a slot and adapted to secure the elastomer (28).

2. The system of claim 1, wherein the elastomer (28) has two ends, one of which is secured to the anchor (20) and the other of which is secured to a second anchor (20).

3. The system of claim 1 or 2, wherein the elastomer (28) comprises one or more single strand elastomers.

4. The system of claim 1 or 2, wherein the anchor (20) further comprises at least one barb (44) adapted to penetrate tissue.

5. System according to claim 1 or 2, wherein the holder (20) further comprises at least one hook (26) adapted to engage with the elastomer (28).

6. System according to claim 1 or 2, wherein the holder (20) further comprises at least one eyelet (30).

7. A system according to claim 1 or 2, wherein the holder (20) is deformable upon application of a predetermined force to release the resilient body (28).

8. The system of claim 1 or 2, wherein the anchor (20) is adapted to be attached to the tissue with at least one staple (46).

9. The system of claim 8, wherein the anchor (20) includes a path of travel adapted to receive the staple (46) to allow lateral movement of the anchor (20) relative to the tissue.

10. The system according to claim 1 or 2, wherein the holder (20) is adapted to be connected to the tissue with at least one suture (134).

11. The system of claim 1 or 2, wherein the holder (20) further comprises a base (33) adapted to receive at least one suture (134).

12. The system according to claim 1 or 2, wherein the holder (20) is adapted to be attached to the tissue with a surgical adhesive.

13. The system of claim 12, wherein the surgical adhesive is a pressure sensitive adhesive.

14. A system according to claim 1 or 2, wherein the resilient body (28) further comprises a tension indicating member.

15. The system of claim 14, wherein the tension indicating member is at least two markings (132) comprising a colorant or structure on the elastomer (28).

16. A system according to claim 1 or 2, wherein at least two anchors (20) are adapted to be attached to tissue on opposite sides of a wound or incision.

17. The system of claim 1 or 2, wherein the tissue is healthy tissue.