Patent Abstract:
Surgical bolts are useful for solid visceral wound hemostasis. The devices utilize flexible, variable depth transfixing bolts that penetrate the viscera. These bolts bring the tissue into apposition and hold said tissue in apposition while the wound heals. These bolts, or soft tissue rivets, overcome the limitations of sutures that are currently used for the same purposes. The devices are flexible, bendable, and conformable in their wet or dry state. The bolts include pressure plates that are capable of exerting compressive pressure over broad areas of visceral wounds without causing tearing of the friable parenchyma. The bolts are placed and removed by open surgery or laparoscopic access. The bolts can be placed into tissue where both sides of the bolt are exposed, or they can be placed blindly into tissue where the bolt does not protrude out of the tissue at its distal end.

Full Description:
RELATED APPLICATIONS 
       [0001]    This application is a continuation of U.S. patent application Ser. No. 13/385,170, now U.S. Pat. No. 8,556,933, which is a continuation of U.S. patent application Ser. No. 11/821,323, now U.S. Pat. No. 8,114,124, which is a continuation-in-part of, and claims priority benefit from, U.S. patent application Ser. No. 10/358,735 filed Feb. 4, 2003, now U.S. Pat. No. 7,235,090, entitled “Method and Apparatus for Solid Organ Tissue Approximation”, the entire contents of all of which are hereby incorporated herein by reference. 
     
    
     FIELD OF THE INVENTION 
       [0002]    The field of this invention relates to devices and methods for trauma and general surgery, combat medicine, and emergency medical services. 
       BACKGROUND OF THE INVENTION 
       [0003]    As recently as the early 1990s, surgical operations for trauma were directed at the anatomic repair of all injuries at time of the initial operation. It was observed during these exercises that many patients became hypothermic, acidotic, and coagulopathic. Patients showing these three signs often died. Death often occurred in the operating room due to exsanguination, or postoperatively, due to the complications of prolonged shock and massive transfusion to replace blood lost as a result of the trauma. 
         [0004]    One of the most notable developments in the recent evolution of surgery has been the reintroduction of the concept of staged laparotomy to overcome the deficiencies of the repair all-at-once approach. This new strategy of staged laparotomy employing new tactics that have been termed damage control is now used in 10% to 20% of all trauma laparotomies. 
         [0005]    This strategy opens the way for a variety of new devices and methods for control of hemorrhage from solid organs or viscera. Although there are procedures for controlling these injuries, none of these procedures utilize optimal devices or tactics in their execution. Each area offers technological opportunities to improve the devices and procedures for applying those devices. 
         [0006]    Sources of hemorrhage within the abdomen that are most difficult to manage include major stellate fractures in the thick, solid, parenchymal organs, especially the liver. Such injuries may involve more than one hepatic lobe, involve massive hemorrhage, and may be caused by severe blunt or penetrating trauma. While the control of most liver hemorrhage is simple, these very severe anatomic wounds are difficult to manage and have a high mortality, sometimes exceeding 80%. Standard approaches to control of these wounds involve packing with gauze or omentum, if available, and deep liver sutures. Each of these techniques has serious limitations and often fails. A major technical problem has to do with the depth to which the sutures can be placed within the liver. The limitation of liver sutures to coapt tissue edges or tamponade deep parenchymal wounds is clear for several reasons. Sutures may be attached to or come pre-mounted to needles of limited size and curvature making deep placement difficult or impossible. The sutures tend to tear through the friable parenchyma. Another problem with sutures is that since they need to be tied off to themselves or other sutures, they form a circular configuration around certain tissues and may strangulate the tissues within that circle. This strangulation causes reduced blood flow and potentially damaging ischemia for those tissues. In addition, the suture does not distribute its force adequately to compress tissues outside of a very narrow plane described by the circle of the suture path. Another key problem with the current treatment is the time taken to achieve suture hemostasis. Massive bleeding must be stopped quickly or the patient will exsanguinate and die. Placement of sutures is a time consuming process given the tools available today, the friable nature of parenchymal tissue, and the undesirability of intra-hepatic gauze packing. 
         [0007]    The size and curvature of currently marketed needles is pre-set by the manufacturer. Current needles are not long or big enough to transfix major liver lacerations. Even if the needle was large, the suture method of repair causes inadequate force distribution to create hemostasis and resist progressive wound tearing. 
         [0008]    New devices, procedures and methods are needed to support the strategy of damage control in patients who have experienced massive visceral injury. Such devices and procedures are particularly important in the emergency, military, and trauma care setting. These new devices, specifically parenchymal bolts, rely on the principles of broad force distribution on the tissue, pressure tamponade, ease of placement, ease of locking in place with the pressure pads, the ability to adjust tension to optimize tissue compression, and the lack of progressive tearing of the friable wound due to the high shear caused by the suture. 
       SUMMARY OF THE INVENTIONS 
       [0009]    This invention relates to an improved haemostatic tissue apposition device for use in trauma care. The present invention is a transfixing trans-parenchymal bolt. Key features of the bolt include column strength, adjustable depth of penetration, flexibility, tissue non-reactivity, quick and simple application, and adjustment of the pressure plates. The trans-parenchymal bolt uses pressure plates that are affixed to the ends of the bolt to distribute the pressure over a wide area of tissue and compress the tissue. Key features of the pressure plates include one-way ratcheting with quick release or a friction lock, ability to quickly and cleanly remove the pressure plate, and the ability to adjust the pressure plate to ensure optimum tissue apposition and compression. The trans-parenchymal bolt generates pressure tamponade to provide for wound hemostasis. The pressure plates are atraumatic structures such as tabs, leafs, solids, meshes, or other structures that distribute force over a wide area of tissue. By contrast, traumatic structures include pointed projections or small thin wires or whiskers that could rip through parenchymal, or other, tissue. The trans-parenchymal bolt may be placed through an open surgical access site or through a laparoscopic access and manipulation system. The trans-parenchymal bolt, or bolt, can act as, perform the function of, or be equivalent to a soft-tissue rivet. The bolt can also be placed blindly into tissue wherein the distal end of the bolt expands to form a pressure plate thus eliminating the need to access the distal end of the bolt to apply the pressure plate. In this embodiment, the distal pressure plate is activated or expanded by control energy or force applied at the proximal end of the bolt, said control energy being transmitted along the length of the bolt by a linkage, coupling, electronic cabling, or the like. The control energy, or force, then expands the distal pressure plate. Release, or re-collapse, of the distal pressure plate can also be accomplished using the same mechanism at the proximal end of the bolt. The distal and proximal pressure plates are not sharp but are blunted and atraumatic and apply distributed pressure to the tissue. 
         [0010]    Once the bolt has been placed, it remains in place either temporarily or permanently. Temporary placement necessitates removal of the bolt. The bolt may be made from materials that permit long-term implantation or it may be fabricated from resorbable materials that obviate the need to remove the bolt in a subsequent surgical procedure. Both the bolt and the pressure plates are fabricated from materials with smooth outer surfaces that do not encourage tissue or clot ingrowth. The bolts and pressure plates are radiopaque and can be visualized on fluoroscopy or X-ray. Thus, the bolts and pressure plates may be removed with minimal re-bleeding. 
         [0011]    The current medical practice of utilizing sutures is not an optimized solution to open visceral wound repair. Sutures were not designed for use in parenchymal tissue. The present invention distinguishes over the current medical practice because the present invention is tailored to the needs of open visceral wound repair. The parenchymal bolts are stiff enough to serve as their own needles, trocars, or stylets. They may be flexed or permanently deformed to achieve the desired tissue compression. They are suited for either open surgical implantation and removal, or they are suited for laparoscopic placement and removal using specialized access, grasping and delivery instruments. When the trans-parenchymal bolts of the present invention are removed from the patient, re-bleeding does not occur because there is minimal penetration of the wound tissues or clot into the interstices of the bolt and pressure plate. 
         [0012]    For purposes of summarizing the invention, certain aspects, advantages and novel features of the invention are described herein. It is to be understood that not necessarily all such advantages may be achieved in accordance with any particular embodiment of the invention. Thus, for example, those skilled in the art will recognize that the invention may be embodied or carried out in a manner that achieves one advantage or group of advantages as taught herein without necessarily achieving other advantages as may be taught or suggested herein. 
         [0013]    These and other objects and advantages of the present invention will be more apparent from the following description taken in conjunction with the accompanying drawings. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0014]    A general architecture that implements the various features of the invention will now be described with reference to the drawings. The drawings and the associated descriptions are provided to illustrate embodiments of the invention and not to limit the scope of the invention. Throughout the drawings, reference numbers are re-used to indicate correspondence between referenced elements. 
           [0015]      FIG. 1A  illustrates a longitudinal cross-sectional view of the parenchymal bolt, according to an embodiment of the invention; 
           [0016]      FIG. 1B  illustrates a lateral cross-sectional view of the parenchymal bolt near one of the ends, according to an embodiment of the invention; 
           [0017]      FIG. 1C  illustrates a lateral cross-sectional view of the parenchymal bolt near the center, according to an embodiment of the invention; 
           [0018]      FIG. 2A  illustrates a side view of the pressure plate and locking nut in cross-section, according to an embodiment of the invention; 
           [0019]      FIG. 2B  illustrates an end view of the pressure plate and locking nut also showing the lock release, according to an embodiment of the invention; 
           [0020]      FIG. 3  illustrates a longitudinal cross-sectional view of the parenchymal bolt, two pressure plates and two locking nuts, according to an embodiment of the invention; 
           [0021]      FIG. 4  illustrates a longitudinal cross-sectional view of the parenchymal bolt, two pressure plates and two locking nuts wherein the parenchymal bolt has been malleably deformed into a right angle bend, according to an embodiment of the invention; 
           [0022]      FIG. 5A  illustrates a typical wound to the liver, according to an embodiment of the invention; 
           [0023]      FIG. 5B  illustrates preparations for open access liver wound hemostasis using three parenchymal bolts, six pressure plates and six ratcheting locks, according to an embodiment of the invention; 
           [0024]      FIG. 5C  illustrates the wound to the liver following temporary repair with three parenchymal bolts, six pressure plates, and six ratcheting locks, according to an embodiment of the invention; 
           [0025]      FIG. 6A  illustrates a wound to the liver being repaired through laparoscopic access by application of a parenchymal bolt, according to an embodiment of the invention; 
           [0026]      FIG. 6B  illustrates application and tightening of a pressure plate and ratcheting lock via laparoscopic instrumentation, according to an embodiment of the invention; 
           [0027]      FIG. 6C  illustrates the wound to the liver following laparoscopic placement of three parenchymal bolts, six pressure plates, and six ratcheting locks, according to an embodiment of the invention; 
           [0028]      FIG. 7A  illustrates a side cross-sectional view of a parenchymal tissue injury with a parenchymal bolt, two pressure plates, and two ratcheting locks prior to tightening, according to an embodiment of the invention; 
           [0029]      FIG. 7B  illustrates a side cross-sectional view of the parenchymal tissue injury during tightening of the ratcheting locks, according to an embodiment of the invention; 
           [0030]      FIG. 8  illustrates a longitudinal cross-sectional view of a parenchymal bolt comprising pressure plates and friction locks, according to an embodiment of the invention; 
           [0031]      FIG. 9A  illustrates a side cross-sectional view of a parenchymal bolt comprising a distal pressure plate that is integral to the bolt and opens to apply pressure to tissue once the bolt has been placed through tissue or released, according to an embodiment of the invention; 
           [0032]      FIG. 9B  illustrates a side cross-sectional view of a parenchymal bolt comprising a distal pressure plate that is integral to the bolt and has opened following partial withdrawal of the sharp trocar, according to an embodiment of the invention; and 
           [0033]      FIG. 10  illustrates a side view of a delivery system for a soft tissue bolt, shown in partial breakaway view, according to an embodiment of the invention. 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0034]    The present invention may be embodied in other specific forms without departing from its spirit or essential characteristics. The described embodiments are to be considered in all respects only as illustrative and not restrictive. The scope of the invention is therefore indicated by the appended claims rather than the foregoing description. All changes that come within the meaning and range of equivalency of the claims are to be embraced within their scope. 
         [0035]      FIG. 1A  illustrates a longitudinal cross-sectional view of a parenchymal bolt  10  of the present invention. The parenchymal bolt  10  comprises an inner core  12 , an outer coating  14 , a central region  16 , a plurality of ends  18 , and a plurality of serrations  20  on one or both ends  18 . The parenchymal bolt  10  further comprises an optional pointed tip or trocar  22 . 
         [0036]    Referring to  FIG. 1A , inner core  12  of the parenchymal bolt  10  is coaxially affixed to interior of the outer coating  14 . The central connecting region  16  is disposed between the ends  18 . One or more of the ends  18  of the parenchymal bolt  10  comprise a plurality of serrations  20  disposed longitudinally, along at least one side of one or more ends  18 . The optional pointed tip or trocar  22  is removably affixed coaxially to one or more of the ends  18 . 
         [0037]    Referring to  FIG. 1A , the inner core  12  of the parenchymal bolt  10  provides column strength and the ability to be malleable or elastomeric, depending on the patient requirements. The preferred configuration of the inner core  12  is that it is malleable and located in the central region  16  only. The ends  18  are, preferably, elastomeric and do not have the malleable inner core  12  disposed therethrough. Another important advantage of having only polymeric material comprise the ends  18  is that the ends can be cut off or trimmed to size once the parenchymal bolt  10  is fully installed or placed in the patient. Column strength is important so that tension may be transmitted through the parenchymal bolt  10 , even when the parenchymal bolt  10  has been bent into an arc. Column strength also permits the parenchymal bolt  10  to be forced through tissue much the same as a suture needle would be forced through tissue. Malleability is important so that the parenchymal bolt  10  can be bent into the correct curvature needed for optimum coaptation of the tissue being repaired. 
         [0038]    The inner core  12  is fabricated from materials such as stainless steel, cobalt-nickel alloys, nitinol, tantalum, titanium, polylactic acid, polyglycolic acid, platinum, and the like. The inner core  12  is preferably radiopaque and visible under fluoroscopy or X-Ray. It is important that the parenchymal bolt  10  be radiopaque. 
         [0039]    The outer coating  14  is fabricated from the same materials as are used to fabricate the inner core  12 . The outer coating  14  may be the same physical structure as the inner core  12 . Preferably, the outer coating  14  is smooth and does not allow tissue ingrowth. The outer coating  14  may be fabricated from polymers such as, but not limited to, polypropylene, polyethylene, polyester, polyurethane, polylactic acid, polyglycolic acid, polyimide or copolymers of these materials. In a preferred embodiment, the bolt  10  comprises radiopaque markers. The markers are fabricated from tantalum, gold, platinum, stainless steel, titanium, nitinol, cobalt nickel alloys and the like. The markers show the extents of the outer coating  14 . The addition of barium, barium compounds, or the like in concentrations of up to about 40% in the polymer provides for radiopacity. 
         [0040]    One or more of the ends  18  comprise an optional sharpened or tapered tip  22  to pierce tissue with minimal resistance. The optional pointed tip or trocar  22  facilitates passage of the parenchymal bolt  10  through tissue. The pointed tip or trocar  22  may be removed to minimize further tissue damage while the parenchymal bolt  10  is in place. In a preferred embodiment, the pointed tip or trocar  22  is removably attached to the ends  18  by a male threaded stub that is mated into a female threaded adapter on the end  18 . A bayonet mount is another suitable method of attaching the pointed tip or trocar  22  to the end  18 . In another embodiment, the pointed tip or trocar  22  may also be longitudinally disposed through the entire core of the parenchymal bolt  10  and is removed by simply withdrawing the trocar  22  from the parenchymal bolt  10 . The removable sharp tip  22 , in a further embodiment, is retractable within the end  18  of the parenchymal bolt  10 . Retraction of the sharp tip  22  is either automatic or manually activated. 
         [0041]    One or more of the ends  18  comprise the plurality of serrations  20  that permit locking with devices that are attached to the parenchymal bolt  10  in a later process. The serrations  20  are, preferably, triangular in shape and project outward from the longitudinal axis of ends  18 . In the preferred embodiment, the serrations  20  comprise triangular projections. One side of the triangular projection is perpendicular to the longitudinal axis of the end  18 . The perpendicular side of the triangle may also be undercut. Another side is tapered away from the end  18  and forms a ramp moving inward from the end  18  toward the center  16  of the parenchymal bolt  10 . 
         [0042]      FIG. 1B  illustrates a cross-section of the parenchymal bolt  10  taken near one of the ends  18 . The cross-sectional view of the end  18  further comprises one or more optional tracking grooves  24  and one or more optional longitudinal ratchet slots  25 . 
         [0043]    Referring to  FIG. 1B , the tracking groove  24  is a slot and is disposed longitudinally along the length of ends  18 . The longitudinal ratchet slot  25  is disposed longitudinally along the length of ends  18 . 
         [0044]    Referring to  FIGS. 1A and 1B , the serrations  20  are disposed within the ratchet slot  25 . The ratchet slot  25  holds and hides the serrations from the tissue as the parenchymal bolt  10  is advanced through the tissue to minimize trauma. The tracking groove  24  is used to provide alignment for parts that will be mated to the parenchymal bolt  10 . By having two sets of tracking grooves  24 , bilateral symmetry is achieved and parts can be mated in two orientations, rather than just one, thus facilitating the mating process. One ratchet slot  25  is required for each set of serrations and two ratchet slots  25  permit orientation of mating parts in more than one orientation. When more than one ratchet slot  25  and tracking groove  24  are used on each end, the second slot  25  or groove  24  is disposed 180 degrees around the end  18  circumference from the first slot  25  or groove  24 . 
         [0045]      FIG. 1C  illustrates a cross-section of the central region  16  of the parenchymal bolt  10 . The central region  16  comprises the core  12  and the outer coating  14 . The outer coating  14  is disposed coaxially around the core  12 . The optional tracking grooves  25  are not shown in this cross-section. 
         [0046]      FIG. 2A  illustrates a cross-sectional view of a pressure plate  26  and a ratcheting lock  28 . The pressure plate  26  further comprises one or more pass through holes  30 . The ratcheting lock  28  further comprises a plurality of locking tabs  32 , a tracking protrusion  34 , and a central hole  36 . 
         [0047]    The ratcheting lock  28  is disposed coaxially with the pass through hole  30  on the pressure plate  26 . The ratcheting lock  28  is either affixed to the pressure plate  26 , is integral to said pressure plate  26 , or is mounted separately outside the pass through hole  30  of said pressure plate  26 . The locking tabs  32  are flexibly affixed to the ratcheting lock  28  and project inward with a vertical edge toward the pressure plate  26  and a ramped edge sloping away from the pressure plate  26 . The tracking protrusion  34  is one or more small projections into the central hole  36  of the ratcheting lock  28 . 
         [0048]    The pressure plate  26  may have a single pass through hole  30  or it may have the plurality of pass through holes  30 . With the plurality of pass through holes  30 , one pressure plate  26  can be used with multiple parenchymal bolts  10 . 
         [0049]    Referring to  FIGS. 1A ,  1 B, and  2 A, the end  18  is configured to mate with the ratcheting lock  28  and the pressure plate  26 . When the ratcheting lock  28  is advanced over one of the ends  18 , through the central hole  36 , the flexible locking tab  32  on the ratcheting lock  28  is bent aside by the ramp formed on the outside of serrations  20  and allows advancement of the ratcheting lock  28  to continue. Pulling backward on the ratcheting lock  28  or pressure plate  26  causes the vertical edge of the locking tab  32  to dig into the perpendicular sides described by the inner edges of the serrations  20  on the ends  18  so the ratcheting lock  28  will not slip backwards. The tracking protrusion  34  slideably mates with the alignment groove  24  on the end  18  to prevent the locking tabs  32  from becoming misaligned with the serrations  20  and inadvertently disengaging. 
         [0050]      FIG. 2B  illustrates an end view of the pressure plate  26  and the ratcheting lock  28 . As seen in this view, the ratcheting lock  28  further comprises a lock release  38 . 
         [0051]    Referring to  FIGS. 2A and 2B , the locking tabs  32  project inward toward the center of the central hole  36  in the ratcheting lock  28 . The lock release  38  is activated by manual pressure or by a laparoscopic instrument to bend back and release the locking tab  32  from the serrations  20  so that the ratcheting lock  28  and pressure plate  26  may be removed from the end  18 . The lock release  38  allows for quick release of the ratcheting lock  28  and pressure plate  26 . In another embodiment, the lock release  38  retracts the tracking protrusions  34  so that the ratcheting lock  28  can be rotated to disengage the locking tabs  32  from the serrations  20  and enable removal of the ratcheting lock  28  and the pressure plate  26  from the parenchymal bolt  10 . 
         [0052]    The pressure plate  26 , the ratcheting lock  28  and the lock release  38  are fabricated from the same materials as are used in fabrication of the parenchymal bolt  10 . All parts are designed with smooth outer surfaces to minimize the opportunity for tissue or thrombus ingrowth. The pressure plate  26  is stiff enough to distribute pressure to gently hold the tissue together while it heals. In a preferred embodiment, the pressure plate  26  and the ratcheting lock  28  are radiopaque. Materials such as barium, barium compounds, or radiopaque metals or the like, comprise at least part of the pressure plate  26  or lock  28 . 
         [0053]    Referring to  FIGS. 1A ,  1 B,  1 C,  2 A and  2 B, the length of the parenchymal bolt  10  ranges from 0.5 cm to 500 cm depending on the tissue being compressed. More preferably, the length of the parenchymal bolt  10  ranges from 2 cm to 50 cm. The diameter of the parenchymal bolt  10  varies and is in proportion to the length of the bolt  10 . Diameter ranges of between 0.5 mm and 10 mm are appropriate for the parenchymal bolt  10 . The pressure plate  26  is sized to the organ being compressed. The pressure plate  26  has roughly rectangular dimensions ranging from a minimum of 0.5 cm to a maximum of 100 cm. The preferred range of sizes for the pressure plate  26  is 1 cm to 20 cm. The pressure plate  26  thickness ranges from 0.5 mm to 30 mm. 
         [0054]      FIG. 3  illustrates a longitudinal cross-sectional view of the parenchymal bolt  10  with two pressure plates  26  and two ratcheting locks  28 . The pointed tip or trocar  22  has been removed in this view. The pressure plates  26  and ratcheting locks  28  have been pushed over the ends  18  of the parenchymal bolt so that the locking tabs  32  have engaged the serrations  20 . 
         [0055]      FIG. 4  illustrates a longitudinal cross-sectional view of the parenchymal bolt  10  with two pressure plates  26  and two ratcheting locks  28 . The parenchymal bolt  10  has been malleably deformed in its central region  16  and maintains that shape because the core  12  has sufficient strength to overcome the elastic forces generated by the outer covering  14 . 
         [0056]      FIG. 5A  illustrates a wound  42  in a liver tissue  40 . The liver is a prime example of parenchymal tissue that often receives damage during abdominal trauma. Note that the parenchymal tissue of the liver  40  is friable and unable to sustain high stresses without fracturing or tearing. 
         [0057]      FIG. 5B  illustrates open surgical preparation for repair of the liver wound  42  according to the methods of the present invention. In this case, three parenchymal bolts  10 , six pressure plates  26  and six ratcheting locks  28  are prepared for the procedure while the liver  40  apposition is accomplished with manual pressure. 
         [0058]      FIG. 5C  illustrates completion of the repair of the wound  42  to the liver  40  using the parenchymal bolts  10 , pressure plates  26  and ratcheting locks  28 . The ratcheting locks  28  are tightened sufficiently to hold the pressure plates  26  firmly against the tissue causing complete wound  42  closure and hemostasis. 
         [0059]      FIG. 6A  illustrates the wound  42  to the liver  40  with the parenchymal bolt  10  being applied by a laparoscopic instrument  44 . In this embodiment, the laparoscopic instrument  44  is a grasper or set of jaws, placed through an axially elongate hollow structure  48 , that may be manipulated by the surgeon from the outside of the patient. 
         [0060]      FIG. 6B  illustrates the wound  42  to the liver  40  following placement of the first parenchymal bolt  10 , two pressure plates  26  and two ratcheting locks  28  using the first laparoscopic instrument  44  and a second laparoscopic instrument  46 . Again, the laparoscopic instruments  44  and  46  are placed through an axially elongate hollow structure  48  that provides access to the internal organs of the patient. The laparoscopic grasping device  46  is placed around the ratcheting lock  28  and is used to advance the ratcheting lock  28  and pressure plate  26  inward against the liver tissue  40 . The laparoscopic grasping device  44  applies tension to the parenchymal bolt  10  so that the pressure plate  26  and the ratcheting lock  28  move relative to the parenchymal bolt  10 . The laparoscopic grasping instruments  44  and  46 , which may be similar to very long nosed pliers, may be replaced by a single instrument that performs both functions of stabilizing the parenchymal bolt  10  and advancing the ratcheting lock  28 . This type of procedure is generally performed under direct vision through a lens and illuminator placed laparoscopically within the surgical field. 
         [0061]      FIG. 6C  illustrates the wound  42  to the liver  40  following laparoscopic repair with three parenchymal bolts  10 , six pressure plates  26  and six ratcheting locks  28 . 
         [0062]      FIG. 7A  illustrates a side cross-sectional view of the wound  42  to parenchymal tissue  40 , in this case the liver  40 , following initial repair with the parenchymal bolt  10  of the present invention. The repair of the wound  42  comprises placement of the parenchymal bolt  10  followed by placement of two pressure plates  26  and two ratcheting locks  28 . 
         [0063]    Referring to  FIG. 7A ,  FIG. 1A  and  FIG. 2A , the pointed tip or trocar  22  has been removed or retracted following full tissue  40  penetration by the parenchymal bolt  10 . Two pressure plates  26  have been applied to the ends  18  of the parenchymal bolt  10  to transfix the tissue  40 . Two ratcheting locks  28  are in the process of being tightened over the pressure plates  26  and the wound  42  is still open. 
         [0064]      FIG. 7B  illustrates the wound  42  in the parenchymal tissue  40  at a point where the ratcheting locks are nearly tightened against the tissue  40 . The wound  42  has achieved nearly complete closure. Additional inward tightening of the ratcheting locks  28  will compress the pressure plates  26  and achieve full wound  42  closure and hemostasis. The parenchymal bolt  10  flexes to accommodate the change in wound geometry as the ratcheting locks  28  are tightened. 
         [0065]      FIG. 8  illustrates another embodiment of the parenchymal bolt  10 , shown in longitudinal cross-section. The parenchymal bolt  10  further comprises an axially elongate shaft  14 , a malleable central component  12 , a sharpened tip  22 , one or more pressure plates  26 , and one or more friction locks  50 . The friction lock  50  further comprises a friction generator  52  and a housing  54 , which further comprises a grasping bump  56 . 
         [0066]    The key enhancement to this embodiment of the parenchymal bolt  10  is the friction lock  50 . The friction lock  50  may be separate or integral to the pressure plate  26 . The friction lock  50  is fabricated from biocompatible polymeric materials such as, but not limited to polyethylene, polypropylene, ABS, PVC, stainless steel, PTFE, titanium, polylactic acid (PLA), polyglycolic acid (PGA), and the like. The PLA or PGA fall under a class of materials that are bioresorbable. These bioresorbable, or resorbable, materials will absorb when implanted in body tissue, over a period of time extending from 1 day to 6 months, preferably in the range of 1 week to 3 months. The formulation of the bioresorbable materials can be modified to adjust the resorption time. Other bioresorbable materials include those fabricated with sugars, collagen, protein, or the like. In the preferred embodiment, the friction lock  50  comprises a friction generator  52 , which is a disc with a hole in the center. The hole is smaller in diameter than the outside diameter of the axially elongate shaft  14  of the parenchymal bolt  10 . The friction generator  52  comprises elastomeric materials that exert an inward pressure and generate friction against the outside diameter of the axially elongate shaft  14 . Such elastomeric materials include, but are not limited to, polyurethane, silicone elastomer, latex rubber, and the like. The friction exerted by the friction lock  50  against the axially elongate shaft  14  is sufficient to resist the force of the tissue resilience once engaged in contact but insufficient to prevent manual movement generated by the surgeon either applying or removing the friction lock  50  from the axially elongate shaft  14 . The housing  54  further comprises a grasping surface  56 , which is a bump or other feature that allows for easy grasping by the surgeon in a wet or slick environment so that the friction lock  50  may be removed retrograde from the shaft  14  of the parenchymal bolt  10 . Other embodiments of the friction lock  50  include those that comprise a jam cleat, an over-center cam, a spring-loaded friction member, and the like. The friction lock  50  preferably does not comprise a release mechanism but in certain configurations, a button or latch to release the friction is required. 
         [0067]      FIG. 9A  illustrates another embodiment of a parenchymal bolt  100  with a distal pressure plate  90  that is pre-affixed to the bolt  100  prior to use in a patient. The bolt  100  comprises a shaft  14 , a trocar  80  further comprising a sharp tip  82  and a trocar handle  84 , at least one distal pressure plate  90 , a connection region  86 , a proximal pressure plate  26 , a lock  50 , and an actuation lever  100 . 
         [0068]    The distal pressure plate  90  is configured to fold against the shaft  14  of the bolt  100  when the bolt  100  is being inserted distally through tissue. When the bolt  100  distal end, which carries the distal pressure plate  90 , has been advanced through the tissue and is released, the distal pressure plate  90  opens, at least partially due to spring force applied, and can exert pressure on the tissue when pulled proximally. The distal pressure plate  90  is affixed to the shaft  14  by the connection region  86 , which can be bendable, can comprise a spring, can comprise an actuator, can comprise releasable locks, or can comprise a hinge. The shaft  14  can be malleable, elastomeric, rigid, pre-bent, shape-memory such that it takes a curved configuration upon exposure to body temperature or a temperature above body temperature generated by Ohmic heating, or the like. 
         [0069]    The distal pressure plate  90 , in this embodiment, comprises narrow plates or arms that are separated from the shaft  14  by slots or gaps that allow for expansion of all but the distal region of the pressure plate  90  where it is affixed to the shaft  14  at the connection region  86 . In an embodiment, the distal pressure plate  90  can be integral to the shaft  14  and be created by slits or slots in the shaft  14  to form the distal pressure plate  90  elements. The distal pressure plate  90  expandable elements can be held against the side of the shaft  14  by releasable locks, such as those that release or are activated when the tip  82  is withdrawn proximally. The proximal pressure plate  26  and lock  50  are applied in the same way as that of other embodiments of the parenchymal bolt  10 . In the preferred embodiment, the proximal pressure plate  26  and lock  50 , which can be a friction lock, are pre-positioned on the shaft  14  of the parenchymal bolt  100  or applier and is advanced by the bolt applier, laparoscopic instrument, or manually by the surgeon. In an embodiment the parenchymal bolt  100  can be applied by an instrument such as a bolt applier, laparoscopic instrument, or the like ( FIG. 10 ). This embodiment can be useful when the distal side of the tissue is not easily accessed by the surgical approach and placement of the distal pressure plate  90  would be difficult or impossible. In an embodiment, the sharp pointed tip  82  is retractable or is withdrawn proximally by the user by pulling on the trocar handle  84  affixed to shaft  80  and further affixed to tip  82  once the tissue has been penetrated. The length of the bolt  100  can be adjusted by trimming with the bolt applier or other instrument such as a cutter or pair of scissors. In another embodiment, the length of bolt  100  can also be adjusted using a telescoping, locking configuration in the shaft  14 . The telescoping shaft  14  eliminates the need for length trimming. This type of bolt  100  can be used to affix prosthetic devices to soft tissue. The actuator lever  100  is affixed near the proximal end of the shaft  14  and can be moved, either by hand or by an instrument, to force the distal pressure plates  90  outward to engage the tissue. 
         [0070]      FIG. 9B  illustrates a cross-section of the bolt  100  of  FIG. 9A  with the distal pressure plate  90  expanded or released. The bolt  100  comprises the shaft  14 , the trocar  80 , the sharp tip  82 , the proximal pressure plate  26 , the lock  50 , the distal pressure plates  90 , the connection region  86 , the actuation lever  150 , an actuation linkage  102 , a linkage lumen  104 , one or more lever arms  106 , a lever arm hinge  108 , an optional distal pressure plate hinge  110 , and one or more shaft windows  112 . 
         [0071]    Referring to  FIG. 9B , the distal pressure plate  90 , in this embodiment, will appear as a series of radial projections or fingers. Integral or separate leaf springs  86  bias the expandable elements of the distal pressure plate  90  to expand outward. The pointed distal tip  82  and its shaft  80  are slidably movable within the shaft  14 . In a preferred embodiment, one or more detents in the shaft  14  mate with protrusions in the shaft  14  to provide a positive positioning index that may be overcome by manual force. In one embodiment, when the distal pressure plate  90  passes beyond tissue, the spring biased pressure plate elements open. In another embodiment, the pressure plate  90  is released when the pointed distal tip  82  and its shaft  80 , which are affixed to each other, are withdrawn proximally. The connection region  86  can comprise a spring, an actuator, releasable locks to keep the pressure plates  90  open, or a hinge. 
         [0072]    In another embodiment, when the control, or actuation, lever  150  is advanced forward, it forces the actuation linkage  102  to slide distally within the linkage lumen  104  and advance the proximal end of the actuation levers  150 . Distal motion of the actuation levers  150  forces the distal pressure plates  90  to open outward around the distal pressure plate hinge  110 . Friction in the system or a lever lock  86 , which can be releasable and controllable from the proximal end of the bolt  10 , or non-releasable, keeps the distal pressure plates  90  open such that they project laterally away from the shaft  14 . Backup reinforcements, such as the lever arms  106  prevent the leafs of the distal pressure plate  90  from rotating substantially beyond a plane perpendicular to the axis of the bolt  100 . 
         [0073]    The distal pressure plates  90  can be configured as wings as shown, or they can be bendable or hinged in the middle such that they open radially or laterally when force is applied at the proximal end of the distal pressure plates  90 . In this embodiment, the proximal end of the pressure plate  90 , which is constrained not to expand radially is moved distally causing the center of the distal pressure plates  90  to bend, bow, or hinge. This arrangement, similar in configuration to a Moly-bolt, for example, can provide for distal fixation and a pressure-plate effect. Transmission of power from the actuation lumen  104  to the lever arms  106  or distal pressure plates  90 , which do not use the lever arm  106 , can occur through a window  112  cut in the side of the shaft  14 . In yet another embodiment, the distal pressure plates  90  comprise shape memory nitinol that is shape-set during heat-treating to expand radially at body temperature. The nitinol-actuated pressure plates  90  can also be configured to expand radially with the application of electrical energy to the pressure plates  90  causing Ohmic or resistive heating of the nitinol elements above body temperature past a transition temperature, such as the austenite start temperature or austenite finish temperature. The nitinol-actuated pressure plates  90  can be heated using adjunctive heaters such as a nickel chromium wire routed around or near the nitinol actuator. Hysteresis effects can keep the nitinol open even when the bolt  100  or pressure plates  90  are exposed to body temperatures or slightly below. The pressure plates  90  in this embodiment can take the shape of ribbons or wings that are longitudinally disposed along the shaft  14  but bend outward radially or laterally to cause the pressure plate effect. The pressure plates  90  can also take the form of a coil of wire that expands to form a ball or other three-dimensional mesh which can serve the function of a pressure plate. 
         [0074]    In an embodiment, the proximal pressure plate  26  can be configured as the mirror image of the distal pressure plate  90 . In this embodiment, the proximal pressure plate  26  is actuable, rather than being pre-attached to the shaft  14  with the lock  50 . The proximal pressure plate  26  of this embodiment can be a Moly-bolt, a balloon, an expanding wire structure or other configuration similar to that described for the distal pressure plate  90  using the same or similar actuation mechanisms or means. In another embodiment, the bolt  100  can be configured to bend in response to shape memory actuators affixed thereto. The actuation of the shape memory actuators can be performed using electrical energy delivered through a delivery system such as that shown in  FIG. 10 . 
         [0075]    Another aspect of the inventions includes the method of use of the bolt  10 . In an embodiment, the bolt  100  is inserted into a patient through the tissue using the fingers or with the aid of an instrument which is axially elongated to provide additional reach into small, narrow spaces unreachable except through undesirable open surgery. The bolt  100  is advanced with its sharp tip  82  exposed through tissue until it has achieved the desired penetration. The sharp tip  82  is then retracted and optionally completely withdrawn from the bolt  100 . The distal pressure plates  90  are expanded by actuation from the proximal end, by automatic means such as shape memory expansion, or by proximal pullback or removal of the core, sharp trocar  80 . Proximal end pressure plates  26  are either applied, actuated, or expanded using the same or similar means as the distal pressure plates  90 . The plates can be adjusted for tightness by causing the proximal pressure plate  26  to slide axially along the shaft  14  and then lock in place with the lock  50 . The instrument or hand is then decoupled from the bolt  100  and removed. The bolt  100  is either left permanently, removed by surgery, or left to resorb into the tissue. The bolt  100  can be used to repair damaged parenchymal tissue, or it can be used to repair damaged muscle such as smooth muscle or striated muscle. The use of soft tissue rivets, such as the bolt  100 , can be used to speed closure of wounds that result from trauma or surgery. The application of a rapid-fire bolt  100  by means of an installation tool (not shown) can result in placement of multiple bolts  100  in a very short period of time. For example, it is possible to place 5 to 20 bolts  100  in one minute or up to one rivet or bolt  10  every 5 seconds using this type of system. 
         [0076]      FIG. 10  illustrates a delivery system  1000  for a soft tissue bolt  100  comprising a main shaft  1002 , a pushrod  1004 , a distal engagement tab  1006 , a grabber control handle  1008 , a pushrod control handle  1010 , an actuator control lever  1012 , a main handle  1014 , one or more grasper tabs  1018 , a grasper hinge  1020 , one or more grasper linkages  1022 , one or more grasper linkage connectors  1024 , one or more electrical input jack  1026 , and one or more grasper electrode  1028 . 
         [0077]    Referring to  FIG. 10 , the main handle  1014  is affixed to the main shaft  1002  near the proximal end of the main shaft  1002 . The pushrod  1004  is affixed, at or near its proximal end to the pushrod control handle  1010  and at or near its distal end, to the distal engagement tab  1006 . The pushrod  1004  is slidably disposed within or near the main shaft  1002 , with respect to which it is oriented generally parallel. The grasper tabs  1018  are rotatably affixed about the grasper hinge  1020 , which is affixed near the distal end of either the main shaft  1002  or the pushrod  1004 . The grasper linkages  1022  are affixed to the grasper tabs  1018  at linkage connectors  1024 . Electrical input jack  1026  is affixed to the main handle  1014 , the pushrod control handle  1010 , or near the proximal end of the main shaft  1002 . The grasper electrodes  1028  are affixed to either the grasper tabs  1018  or the distal engagement tab  1006  and are operably connected to the electrical input jacks  1026  by an electrical bus, which can be, in the illustrated embodiment the grasper linkages  1022 . 
         [0078]    The delivery system  1000  can be used in conjunction with a laparoscopic or thoracoscopic trocar, for example, or through an open surgical port to deliver the soft tissue bolt  100  to a surgical target site. Referring to  FIGS. 9A and 9B , the operator grasps the delivery system  1000  by the main handle  1014  with the distal engagement tab  1006  releasably engaging the distal pressure plate  90  expansion control lever  150  on the bolt  100 . In another embodiment, the distal graspers can be used to releasably engage the distal pressure plate  90  control lever  150  on the bolt  100 . In this embodiment, the distal engagement tab  1006  can be used to withdraw the obturator, shaft  80 , or sharpened point of the bolt either partially or fully proximal and out of the bolt  100 . In this embodiment, the grasper electrodes  1028  can be used to deliver electrical energy to either bend the bolt  100  or to radially expand the distal pressure plates  90  by shape memory effects using nitinol, or the like in one or both applications. The distal engagement tab  1006  or the grasper tabs  1018  can be configured, in one or more embodiments, to provide cutting action to cut off excess length of the soft tissue rivet, or bolt,  100  during or after the implantation and securing process has been completed. Alternatively, an additional cutter  1030  can be affixed near the distal end of the delivery system  1000  to cut the bolt  100  to length. This is facilitated by removal of any metallic core materials leaving primarily polymeric bolt  100  shaft materials, which can more easily be severed. Control over the cutting action is applied at or near the proximal end of the delivery system  1000  and the control is transmitted to the cutting mechanism by linkages such as the grasper linkages  1022  or the pushrod  1004 . 
         [0079]    The components of the delivery system  1000  can be fabricated from polymeric materials such as, but not limited to, polycarbonate, polypropylene, polyethylene, PEEK, polyvinyl chloride, acrilonitrile butadiene styrene, polysulfone, or the like. The components can also be fabricated in part, or in whole from metals such as, but not limited to, stainless steel, cobalt nickel alloy, titanium, nickel titanium, tantalum, or the like. The length of the main shaft can range from 2 cm to 50 cm and the diameter of the main shaft can range from 1 mm (3 French) to 25 mm (75 French). The delivery system  1000  can be releasably affixed to the bolt  100  in singles. In another embodiment, multiple bolts  100  can be loaded into the delivery system to permit rapid fire, multiple applications. The delivery system  1000  can control the expansion of the distal, or second, pressure plate. The delivery system  1000  can control retraction of the obturator. The delivery system  1000  can control bending of the bolt  100 . 
         [0080]    Application of the parenchymal bolt system provides improved speed of solid organ trauma repair and minimizes the chance of tissue tearing or fracture, relative to the use of sutures for said repair. The parenchymal bolt system provides pressure tamponade to the injured tissue to provide for hemostasis and maximize the recovery process while minimizing complications common to suture-based approaches. 
         [0081]    The present invention may be embodied in other specific forms without departing from its spirit or essential characteristics. For example, the ratcheting locks could be replaced by simple threaded nuts that engage threads on the parenchymal bolt. The distal pressure plate can comprise one or more radially expandable wings such as are found in a hollow wall anchor, or the distal pressure plate can comprise a fluid-filled balloon such as a non-elastomeric balloon or an elastomeric, Foley-type balloon, or they can be of a radially different shape such as a three-dimensional wire mesh or a solid such as when a hydrogel, constrained within a water permeable membrane, expands due to fluid uptake to swell into a flexible volume. The described embodiments are to be considered in all respects only as illustrative and not restrictive. The scope of the invention is therefore indicated by the appended claims rather than the foregoing description. All changes that come within the meaning and range of equivalency of the claims are to be embraced within their scope.

Technology Classification (CPC): 0