System for repairing biological tissues

Abstract

The present invention relates to a system for repairing biological tissues comprising a coupling device comprising at least a first element couplable to a second element, the system further comprising at least two insertion elements each comprising a proximal end connected or connectable to either said first element or said second element of the coupling device, and a pointed distal end, wherein said at least two insertion elements, when in operational configuration, are arranged with a 180° rotational symmetry, and wherein, when the first element is coupled with the second element, the coupling device is adapted to ensure a stable but reversible connection between said at least two insertion elements.

Description

[0001] System for repairing biological tissues

[0002] Field of the invention

[0003] The present invention relates to a system for repairing biological tissues and to an applicator for the insertion and / or removal of said system into and / or from an injured biological tissue in order to repair it.

[0004] Prior art

[0005] Suture (from the Latin sutura, “sewing”) refers to the surgical procedure that allows for the stable approximation of the edges of a wound, promoting its healing. It consists of the application of one or more stitches with traditional instruments such as needles and suture threads, tightened and secured with special knots, or with mechanical means such as the more modem automatic suturing devices. In laparoscopic and robotic surgery, metallic staples, the so-called clips, are mostly used. Clips and staples are also employed in cutaneous sutures, for which the use of special plasters, steri strips, is increasingly widespread, particularly appreciated by patients as they can be applied without invasive manoeuvres. Great interest has recently been aroused by synthetic glues (cyanoacrylates) or biological glues (fibrin glue) tested in various situations ranging from the suture of skin wounds to the treatment of haemorrhagic lesions of certain parenchymal organs such as the liver and spleen, to the reinforcement and protection of traditional anastomoses.

[0006] Traditional sutures, however, have certain limitations in the surgical treatment of soft tissues. In particular, the failure of tissue healing after surgical repair still has a very high incidence, from 5 to 40%, with very serious consequences from a clinical, health, and economic point of view. The causes of failed surgical healing have been known and described for over one hundred years and are primarily identified in three factors: a) reduced vascularisation, b) tension of the edges, c) lack of congruency in the approximation of the edges. Traditional sutures physically contradict these principles since the tightening of the threads reduces or even blocks blood circulation, and resistance to divergent forces is obtained precisely by increasing the tension of the threads acting on the edges, consequently distorting the profile. It is known that the best scars are those obtained, when possible, by mere approximation with simple plasters that do not block circulation and leave minimal or no evidence. Conversely, scars obtained with large stitches, which are nevertheless necessary for addressing tissues subject to movement and acting forces, leave visible outcomes such as keloids, atrophic skin, dyschromia, and blemishes, superficial signs of incorrect healing. To this must also be added the ability to perform the most correct possible suture, a factor that also depends on the experience of the operator and the use of the proposed materials. This variability, combined with the technical difficulty of performing a correct suture in difficult anatomical sites, is a further element of failure.

[0007] To date, the problem has been addressed by attempting to improve the traditional suture technique.

[0008] Separate stitches rather than “continuous” ones have been proposed, non-absorbable threads, absorbable threads with medium or long-term resorption.

[0009] Recommendations have been made regarding the spacing to be maintained in the placement of the stitches and their number in relation to the length of the wound; all of this, however, has not solved the underlying problem.

[0010] As confirmation of this, some proposals aim to address the problem of tension on the edges by reducing the forces applied thereto, but without improving the mode of approximation of the tissues. The current employed solutions aim to reduce excessive tension on the edges by resorting to two methods:

[0011] ^Component separation-, consists in the partial sectioning of the aponeuroses that bind the rectus abdominis muscle to the lateral muscles, in this way, the rectus muscle is distanced from the latter and a relatively easier closure along the midline is achieved. The reduced lateral tension obtained through the definitive sectioning of the aponeuroses improves the chances of healing success. This intervention is indicated only in the case of repair of large incisional hernias or “abdominal wall disasters”; it is not used in the primary closure of wounds and still creates further damage on a wall that has already undergone previous surgical injuries. Finally, it should be noted that it is not technically simple to perform and is not free from possible complications; b) Temporary paralysis of the lateral abdominal muscles with Botox (botulinum toxin): follows the same operating principle as the previous technique and offers the advantage of being reversible, an advantage that, however, becomes a limitation when its action ceases, restoring tensions to their maximum values. The indications are limited as above, and the costs and relative manageability have not promoted its diffusion to date.

[0012] These proposals are extreme, expensive and not applicable in all situations.

[0013] Other innovations concern surgical robots: their use has been proposed to facilitate the surgeon’s work. In particular, the surgical robot allows one to address issues related to the making of a valid suture, thus facilitating laparoscopic sutures, which are even more difficult to perform. However, in addition to not addressing the underlying problem, the use of the robot involves extremely high costs and limited possibility of diffusion for such applications.

[0014] In conclusion, the market currently lacks an innovative proposal that is easy to use, low in cost, and widely applicable to overcome the aforementioned problem.

[0015] The possibility of having a system for the repair (the suture) of biological tissues that is easy to use, that allows to facilitate the recruitment of muscle bands, that gives the tissue-system assembly a solid structural stability, that eliminates the problems caused by suture knots, that distributes the loads evenly along the tissue lesion and that ensures the vascularisation of the tissue is therefore a felt need in the market.

[0016] Summary of the invention

[0017] The objective of the present invention is therefore to provide a system for the repair (the suture) of biological tissues (and its applicator) that is easy to use, that allows to facilitate the recruitment of muscle bands, that gives the tissue-system assembly a solid structural stability, that eliminates the problems caused by suture knots, that distributes the loads evenly along the tissue lesion and that ensures the vascularisation of the tissue.

[0018] This objective is achieved by a system for repairing biological tissues and by an applicator for the insertion and / or removal of said system into and / or from an injured biological tissue in order to repair it, as outlined in the accompanying claims, the definitions of which form an integral part of the present description.

[0019] Brief description of the figures

[0020] The invention will be better understood from the following detailed description of its preferred embodiments, provided by way of example and therefore not limiting, with reference to the accompanying figures, in which:

[0021] - Figure 1A shows an embodiment of the system 10 according to the present invention;

[0022] - Figure IB shows an alternative embodiment of the system 10 according to the present invention;

[0023] - Figures 2A, 2B, 2C, and 2D show embodiments of insertion elements 18 of the system 10 according to the present invention;

[0024] - Figures 3A to 12 show embodiments of coupling devices 12 of the system 10 according to the present invention;

[0025] - Figure 13 shows an embodiment of the applicator 100 according to the present invention;

[0026] - Figures 14 to 17B show sectional views of details of the applicator of Fig. 13;

[0027] - Figure 18 shows an alternative embodiment of the applicator 100 according to the present invention;

[0028] - Figures 19A and 19B show sectional views of details of the applicator of Fig. 18;

[0029] - Figure 20 shows one of the insertion tests of insertion elements 18 according to the present invention;

[0030] - Figure 21 shows prototypes of insertion elements 18, according to the present invention, tested and the meat samples used for the analysis;

[0031] - Figure 22 shows the load-displacement curves of the prototypes of Fig. 21; - Figure 23 shows images of insertion elements 18 and some coupling devices 12 according to the present invention printed using a 3D printer.

[0032] In the accompanying figures, identical or similar elements will be denoted by the same reference numerals.

[0033] Detailed description of the invention

[0034] With reference to Figures 1 to 12, a first object of the present invention is shown, namely a system 10 for repairing biological tissues comprising a coupling device 12 comprising at least a first element 14 couplable to a second element 16, the system 10 further comprising at least two insertion elements 18 each comprising a proximal end 20 connected or connectable to either said first element 14 or to said second element 16 of the coupling device 12 and an acuminate distal end 22, wherein said at least two insertion elements 18, when in operative configuration, are positioned with 180° rotational symmetry to each other, wherein when the first element 14 is coupled with the second element 16, the coupling device 12 is adapted to ensure a stable but reversible connection between said at least two insertion elements 18. In Figure 1A a first preferred embodiment of the system 10 according to the present invention is shown, whereas in Figure IB a second preferred embodiment of the system 10 according to the present invention is shown.

[0035] Preferably, said at least two insertion elements 18 have the same shape. Alternatively, said at least two insertion elements 18 preferably have different shapes.

[0036] According to a preferred embodiment of the system 10 according to the present invention, at least one of said at least two insertion elements 18 preferably has a spiral shape.

[0037] According to a preferred embodiment of the system 10 according to the present invention, at least one of said at least two insertion elements 18 comprises a through cavity 24 positioned longitudinally along part or all of the length of the insertion element 18. Preferably, said cavity 24 is an internal cavity within each insertion element 18 or is a surface groove positioned longitudinally along part or all of the length of the insertion element 18. With particular reference to Figures 3 to 12, according to a preferred embodiment of the system 10 according to the present invention, the coupling device 12 is preferably selected from: interlocking coupling device 26, screwing coupling device 28, counter-rotating motion coupling device 30, adjustable closure coupling device 32, T-closure coupling device 34, bar-closure coupling device 36, suture wire-assisted coupling device 38, adjustable and reversible closing coupling device with guide 40, adjustable, reversible and external closing coupling device 42, adjustable, reversible, and comprised in the insertion elements, closing coupling device 44.

[0038] According to a preferred embodiment of the system 10 according to the present invention, both the coupling device 12 and the insertion elements 18 may preferably be made of biocompatible and biodegradable material, or of non-biodegradable material. In particular, both the coupling device 12 and the insertion elements 18 may preferably be made of biocompatible and non-biodegradable materials such as nylon or polypropylene. Preferably, both the coupling device 12 and the insertion elements 18 may be made using different production techniques, such as injection moulding or additive manufacturing techniques, such as selective laser sintering (SLS), for example.

[0039] In particular, according to a preferred embodiment of the system 10 according to the present invention, the insertion elements 18 preferably have a helical shape (however, alternative embodiments provide for other shapes, therefore not helical), and when they are introduced perpendicularly at the two adjacent edges of injured tissue to be repaired (sutured), they allow to retain and maintain said edges in contact thanks to the coupling device 12 which acts as a coupling-fixing system (Fig. 1A).

[0040] The coupling device 12 may be a separate component from the insertion elements 18, but may also be housed within the insertion elements 18 themselves.

[0041] The insertion elements 18 may also be inserted into the tissue through their distal end 22 and be brought together by means of the coupling device 12. The insertion elements 18 preferably have a tapered geometry and present an acuminate tip at their distal end 22. In particular, the dimensional parameters of such elements may vary depending on the target tissue, the method of insertion, and the type of procedure to be performed (open surgery, minimally invasive surgery). In detail:

[0042] - the insertion elements 18 may have a fixed or variable external diameter / thickness. In particular, the diameter / thickness may vary following a defined pattern, either continuously or discontinuously;

[0043] - the insertion elements 18 may have different lengths depending on the tissue to be repaired (sutured) and the depth of penetration required in the tissue;

[0044] - the insertion elements 18 may have, along their length, a constant and / or variable pitch from the proximal end 20 to the distal end 22 and vice versa. They may also have different pitch from one another;

[0045] - the insertion elements 18 may have, along their length, a constant and / or variable cross-sectional area from the proximal end 20 to the distal end 22 and vice versa. The insertion elements 18 may also have different cross-sectional areas from one another and may exhibit geometric profiles such as circular, semicircular, triangular, square, etc. A circular profile (Fig. 2A) facilitates sliding within the target tissue, whereas a semicircular profile (Fig. 2B), in addition to facilitating sliding, also ensures greater grip on the tissue, conferring structural stability to the element once implanted. The choice of geometric profile is therefore functional to the ability of the insertion elements 18 to slide and anchor within the target tissue. Such choice may also be influenced by the geometric and dimensional requirements related to the designated manufacturing process for the production of said elements (e.g., injection moulding technique);

[0046] - the insertion elements 18 may have a conical geometry, that is, at the distal end 22 the diameter may be greater than the diameter at the proximal end 20, or vice versa;

[0047] - the insertion elements 18 may also be hollow internally (Fig. 2C) and / or have on their surface grooves or recesses (Fig. 2D) with different geometric profiles (circular, oval, square, etc.). The possible presence of cavities and grooves / recesses is functional to the possible passage of a rigid guide whose purpose is to facilitate the insertion of the insertion element 18 into the target tissue;

[0048] - the insertion elements 18 may have portions characterised by thickness variations or discontinuities, for example they may have a stop feature for the blocking of possible rigid guides, which are inserted and / or coupled to said elements 18 to facilitate their insertion into the target tissue.

[0049] The distal end 22 with an acuminate tip may have different cutting profiles (such as for example: conical, ellipsoidal, pyramidal section, double curvature cutting profile, etc.) which facilitate its insertion into the target tissue. Said insertion preferably occurs perpendicularly (but not only) to the wound to be repaired (sutured) by simple rotation and / or translation along the entire length (or even only partially) of the insertion elements 18 at suitable intervals depending on the type of tissue and the tensile loads to which it is subjected.

[0050] The coupling device 12 comprises several components, the number of which may vary depending on its various configurations. The coupling device 12 may also be housed within the insertion elements 18.

[0051] Preferably, the first element 14 and the second element 16 of the coupling device 12 are complementary to each other.

[0052] The operating principle of the coupling device 12 consists in approaching and firmly retaining the two proximal ends 20 of the insertion elements 18, previously inserted into the two adjacent edges of the target tissue. In this way, the coupling device 12 gives the tissuesystem 10 assembly a solid structural stability.

[0053] The coupling device 12 in its various embodiments may vary depending on the target tissue, its method of insertion and the type of procedure to be performed (open surgery, minimally invasive, etc.).

[0054] The coupling mechanism between the insertion elements 18 via the coupling device 12 (and its elements 14 and 16) may take place through various mechanisms, such as for example: interlocking (Fig. 3), rotation / screwing (Fig. 4A and 4B), counter-rotating motion (Fig. 5), adjustable closure (Fig. 6A and 6B), T-closure (Fig. 7), bar-closure (Fig. 8), suture wire- assisted (Fig. 9), adjustable and reversible closure with guide (Fig. 10), adjustable, reversible, and external closure (Fig. 11). The coupling device 12, and therefore also its elements: first element 14 and second element 16, may be assembled / connected to the insertion elements 18 by different principles.

[0055] Below are some non-limiting examples of coupling devices 12: a. interlocking (Fig. 3): this coupling device 12 is composed of two elements: a first element 14 and a second element 16, which have geometries such as to allow coupling via an interlock / undercut present in one of the elements 14; 16. In particular, the first element 14 may have a final section that may possibly be acuminate (but not only), which allows the insertion of its first portion inside the second element 16. The overall section of the coupling device 12 may have, for example, a circular, square, hexagonal or octahedral geometry, etc. The element of the coupling device 12 that allows insertion may also have small windows that allow the compression of its geometry and the reduction of its bulk at the time of passage through the accommodating hole of the second element 16. The second element 16 preferably has a geometry that completely houses the acuminate tip of the first element 14; b. rotation / screwing (Fig. 4A and 4B): this coupling device 12 preferably provides for the use of a screwing system, which has two components: the first element 14 (screw) and the second element 16 (nut) respectively present in the insertion elements 18. The first element 14 component features a support surface and a screw with a threading that allows insertion by rotation of the first element 14 component into the second element 16 component (nut). This system may also have a further variant whereby the second element 16 component (nut) is itself composed of several parts, in particular the nut may be composed of a threaded cylinder (nut) with a through hole at the base of the structure that allows free coupling thanks to a threaded pin (Fig. 4B). The threaded pin is preferably screwed into a threaded support surface (present at the medial end of one of the insertion elements 18) that allows the nut to be anchored in position and allows its free rotation around the threaded pin. In this way, the coupling occurs by rotation of the nut around the screw present in the other insertion element 18; c. counter-rotating motion (Fig. 5): this coupling device 12 preferably has 3 components. Two components are characterised by nuts, which are placed at the medial ends of the insertion elements 18. The nuts have threadings with opposite directions (right-hand and left-hand). The third component has two threaded distal ends, which also have opposite directions (right-hand and left-hand) so as to couple with the nuts by screwing. In particular, the third component has in the middle a thickness that acts as a small nut, which facilitates the rotation of its ends during insertion. This coupling device preferably provides that the two ends of the nuts are progressively brought closer together, thanks to the rotation of the third component, which, having two threaded ends with opposite direction, pulls the nuts towards the centre simply by rotation; d. adjustable closure (Fig. 6A and 6B): this coupling device 12 preferably comprises a first element 14 and a second element 16, which are laid on the insertion elements 18. The first element 14 acts as an eyelet and is characterised by a recess (which may have different geometric profiles) in which there is a cantilevered structure. The second element 16 has a longitudinal structure (length and width much greater than the thickness) which has several protrusions on one of the two major surfaces. Such protrusions are capable of passing through the eyelet present in the first element 14 but are retained by the cantilevered beam present in the first element 14. The coupling mechanism recalls the so-called “cable tie” system; for this reason, the distance between the first element 14 and the second element 16 may be adjusted at the user's discretion; e. T-closure (Fig. 7): this coupling device 12 preferably has a first element 14, a second element 16, and a third element. The first element 14 and the second element 16 are laid on the proximal ends 20 of the insertion elements 18 and have the same geometry. In particular, this is a structure with a geometry having a cantilevered beam in the proximal part that is oriented along the plane orthogonal to the axis of the stem that supports the cantilevered beam in the middle. The first element 14 and the second element 16 are coupled by means of a third element, which in turn has a recess inside with a geometry that allows the insertion of the two elements 14 and 16. The first element 14 and the second element 16 are inserted vertically into the recess of the third element and are retained by an interlocking system with undercut; f. bar-closure (Fig. 8): this coupling device 12 preferably consists of a first element 14 and a second element 16, whose distal ends are laid on the insertion elements 18. The first element 14 has a geometry similar to a toroidal crown which may have constant section (not necessarily). The second element has a geometry that has a bar oriented orthogonally with respect to the axis of the insertion element 18. The coupling mechanism occurs by simple introduction of the bar (second element 16) through the hole of the toroidal crown of the first element 14; g. suture wire-assisted (Fig. 9): this coupling device 12 comprises a first element 14 and a second element 16, which terminate with a section equal to that of a suture wire and are laid in the two proximal ends 20 of the insertion elements 18. The coupling mechanism is based on the simple execution of a single knot or multiple knots, as occurs in surgical suturing; h. adjustable and reversible closing with guide (Fig. 10): this coupling device 12 preferably provides for the use of three elements: a first element 14, a second element 16 and a third element. The first element 14 has a cylindrical geometry with a central hollow square portion, on the sides of the square recess two inclined plates protrude which make up the locking system. The second element 16 has a wire geometry with small spheres and a smooth end which may be overmoulded with the suture thread guided by the surgical needle or directly with the latter. The first element 14 and the second element 16 are laid on the insertion elements 18 with the interlock opening facing inward. The coupling mechanism occurs through the insertion of the second element 16, first through the first element 14 of one of the two insertion elements 18, and then it is guided by a surgical needle also through the first element 14. Once the ideal positioning is achieved, it is possible to cut the guide wire with the needle and also part of the excess second element 16. This type of coupling system allows the decoupling of the components: by applying two bending moments on the sides of the first element 14, it is possible to open the interlock plates and obtain the reversibility of the positioning; i. adjustable, reversible and external closing (Fig. 11): this coupling device 12 preferably provides for the use of three components: two first elements 14 and a second element 16. The first elements 14 have a cylindrical geometry with a central hollow square portion, on the sides of the square recess two inclined plates protrude which make up the locking system. The second element 16 has a wire geometry with small spheres and a smooth end which may be overmoulded with the suture thread guided by the surgical needle or directly with the latter. The first elements 14 are laid on the insertion elements 18 with the interlock opening facing inward therein. The coupling mechanism occurs through the insertion of the second element 16, first through one first element 14 of one of the two insertion elements 18, and then it is guided by a surgical needle through the other first element 14 not yet traversed. Once the ideal positioning is achieved, it is possible to cut the guide wire with the needle and also part of the excess second element 16. This type of coupling system allows the decoupling of the components: by applying two bending moments on the sides of the first elements 14, it is possible to open the interlock plates and obtain the reversibility of the positioning. Differently from the adjustable and reversible closing with guide system, this system provides for the passage of the second element 16 through the entire system of the insertion elements 18, as well as the use of a straight needle for guiding the second element 16; j. adjustable, reversible closing included in the insertion elements 18 (Fig. 12): this coupling device 12 preferably provides for not using any additional component to create the coupling device 12. In particular, the approximation system for closing the two insertion elements 18 is already included in the proximal ends 20 of the insertion elements 18. The closing is housed inside the internal diameter of the coil and parallel and coinciding with the plane of the coil. Said coil where the coupling device 12 is present may have a pitch equal to or different from the others and may also continue in the same direction as the other coils or in a different direction.

[0056] The coupling device 12 present in the two insertion elements 18 may be identical, but not necessarily.

[0057] With reference to Figures 13 to 19B, a second object of the present invention is shown, namely an applicator 100 for the insertion and / or removal of the system 10, as described above, into and / or from an injured biological tissue in order to repair it, comprising a main body 102 in turn comprising: a fixed grip handle 104, a movable drive device 106 mechanically connected to a motion transmission mechanism 108 of the drive device 106, a stem 110 comprising a cavity 112 for housing the system 10 and a translatory mechanism 114, wherein the motion transmission mechanism 108 of the drive device 106 is further mechanically connected to the translatory mechanism 114 which in turn is connected to the system 10 housed in the cavity 112 of the stem 110, thereby allowing a translatory motion of the system 10 within the cavity 112 of the stem 110. Preferably, the motion transmission mechanism 108 and the translatory mechanism 114 may operate using toothed gears or other mechanisms such as, for example, mechanisms based on connecting rods or motorised mechanisms using actuators which allow the roto- translation of the system 10 within the cavity 112 of the stem 110 of the applicator 100.

[0058] According to a preferred embodiment of the applicator 100 according to the present invention, the applicator 100 may preferably be made of polymeric or metallic material (such as steel) or both.

[0059] According to a preferred embodiment of the applicator 100 according to the present invention, the motion transmission mechanism 108 of the drive device 106 comprises a first toothed unit 116 integral with the drive device 106, at least one first toothed wheel 118 couplable with the toothing of said first toothed unit 116, a second toothed wheel 120 couplable with the toothing of the first toothed wheel 118, wherein said second toothed wheel 120 is couplable with the translatory mechanism 114 of the stem 110.

[0060] According to a preferred embodiment of the applicator 100 according to the present invention, the at least one first toothed wheel 118 comprises a ratchet mechanism 122 comprising a third toothed wheel 124 integral, coaxial and parallel to the first toothed wheel 118 and a plurality, preferably three, of spring systems 126 radially arranged around the third toothed wheel 124, wherein each spring system 126 comprises a spring 128 coupled to a lever 130 having a tapered portion, wherein the spring 128 abuts against the tapered portion of the lever 130 so as to push the tapered portion of the lever 130 against the toothing of the third toothed wheel 124. Preferably, the spring systems 126 are in a number between three and ten.

[0061] According to a preferred embodiment of the applicator 100 according to the present invention, the applicator 100 is preferably composed of an assembly of components which, through their synergistic action, allow the insertion of the system 10. The applicator 100 preferably comprises a stem 110 with a geometry that allows its use in minimally invasive surgery, that is, laparoscopically, and may have reduced dimensions to be used in open surgery. It is equipped with a fixed grip handle 104 and a movable drive device 106, which allows the operation of the applicator 100, the movement provided by this device 106 is transformed into a rotation in the plane orthogonal to its movement thanks to a system of toothed wheels. The application of the various insertion elements 18 is performed gradually thanks to a ratchet mechanism 122 that allows the movable drive device 106 to be actuated several times to insert the system 10. The stem 110 of the applicator 100 allows the roto- translation of the insertion elements 18 together with the coupling devices 12, which have dimensions such as to allow passage through the stem 110 without hindrance. In particular, the applicator 100 is preferably composed of 4 systems:

[0062] 1. actuation system: it consists of a fixed grip handle 104 which is integral with the outer part, the so-called main body 102, of the applicator 100 that houses and protects the other systems. It also comprises a movable drive device 106 that acts as a lever to actuate the internal mechanism of the applicator 100. The movable drive device 106 rotates around its axis which is integral with the main body 102, the actuation of the movable drive device 106 is facilitated by the presence of the fixed grip handle 104. The first toothed unit 116 is also integral with the movable drive device 106, the first toothed unit 116 has a geometry resembling a fraction of a toothed wheel circumference; when the movable drive device 106 rotates, the first toothed unit 116 also rotates by the same angle. In turn, the large spring 132 is stretched;

[0063] 2.motion transmission system: it is composed of the assembly of several toothed wheels which, thanks to the initial rotation transmitted by the movable drive device 106 to the first toothed unit 116, allows the actuation of the first toothed wheel 118. The first toothed wheel 118 has dimensions such that an increase in the number of revolutions is expected. The first toothed wheel 118 is integral with the axis of rotation on which a third toothed wheel 124 lies, functioning as the ratchet mechanism 122. The motion is transmitted when the direction of rotation of the third toothed wheel 124 is suitable to engage with the recesses of the second toothed wheel 120. The second toothed wheel 120 has a conical toothing, which allows it to couple with the translatory mechanism 114 preferably comprising a toothed conical wheel 134; in this way, the rotation of the toothed conical wheel 134 occurs in a plane orthogonal to that of the second toothed wheel 120. The toothed conical wheel 134 is finally firmly connected to a stem 110 within which the insertion elements 18 lie. The dimensions of the second toothed wheel 120 and of the toothed conical wheel 134 are such as to allow a precise number of rotations of the toothed conical wheel 134 in order to favour the gradual insertion of the insertion elements 18 (requiring actuation of the movable drive device 106 a precise number of times depending on the dimensional characteristics of the insertion elements 18);

[0064] 3.ratchet return system: this system ensures the transmission of motion of the second toothed wheel 120 only when the movable drive device 106 is actuated. Since the insertion of the insertion elements 18 occurs gradually, the movable drive device 106 must be actuated several times to fully insert the insertion element 18. However, this requires the return of the movable drive device 106 to the initial position, which must not transmit motion to the second toothed wheel 120 during its return to position. For this purpose, a ratchet mechanism 122 has been provided, which comprises a third toothed wheel 124 with special teeth that can engage with small levers 130 that rotate around axes of rotation integral with the second toothed wheel 120. These levers 130 are pushed towards the axis of rotation of the third toothed wheel 124 by the presence of small springs 128 integral with the second toothed wheel 120, which allow the engagement of the levers 130 when the movement of the third toothed wheel 124 coincides with the actuation of the movable drive device 106, whereas, when the movable drive device 106 returns to position thanks to the large spring 132, the movement is not transmitted because the levers 130 slide along the profile of the toothing of the third toothed wheel 124;

[0065] 4. applicator stem guide system: the stem 110 is integral with the toothed conical wheel 134 and therefore performs the same number of revolutions as the toothed conical wheel 134. The stem 110 is hollow inside and has grooves 136 which form a helical guide in which the insertion elements 18 can slide. The pitch of the helical grooves 136 matches the dimensions of the insertion elements 18, allowing their rotation within the stem 110. The translation of the insertion elements 18 occurs thanks to the presence of a fixed worm screw 138.

[0066] According to an alternative embodiment of the applicator 100 according to the present invention, and in particular with reference to Figures 18 to 19B, the applicator 100 is alternatively composed of an assembly of 3 systems which, through their rotation, allow the insertion of the insertion elements 18. The applicator 100 comprises a stem 110 having a geometry that allows its use in minimally invasive surgery, that is, laparoscopically, but it may have reduced dimensions to be used in open surgery. It is equipped with a fixed grip handle 104 and a movable drive device 106 which enables its actuation. The rotational movement of the movable drive device 106 with respect to the fixed grip handle 104 allows the rotation of the insertion elements 18 along the grooves 136 of the stem 110. The application of the various insertion elements 18 is performed gradually thanks to a roto- translational mechanism that allows the forward movement of the insertion elements 18 along the stem 110. At the interface between the fixed grip handle 104 and the movable drive device 106, a ratchet mechanism 122 is preferably present, which allows the movable drive device 106 to be actuated several times to insert the system 10. The stem 110 allows the roto-translation of the insertion elements 18 together with the coupling devices 12, which have dimensions such as to allow passage through the stem 110 without hindrance.

[0067] In particular, the applicator AP is formed by three systems:

[0068] 1. actuation system: this system is formed by two components (the fixed grip handle 104 and the movable drive device 106) which are coupled together by means of screws; its structure is made so as to protect the systems contained within it and also serves as a supporting structure for the blocking of the worm screw 138 by means of blocking elements such as, for example, nuts. The rotation of the movable drive device 106 makes it possible to actuate the motion transmission mechanism 108 and the translatory mechanism 114. The movable drive device 106 rotates around the fixed grip handle 104. The movable drive device 106 can transmit rotation in two ways: the first provides for the direct transmission of rotation thanks to an integral coupling between the movable drive device 106 and the stem 110, in this way there is direct manual rotation transmission; the second provides to connect the movable drive device 106 to the stem 110 by means of a transmission system made with toothed wheels which allow the rotation of the insertion elements 18 around the axis of the worm screw 138;

[0069] 2. motion transmission system with toothed wheels: this system is formed by the assembly of several toothed wheels which, thanks to the initial rotation transmitted by the movable drive device 106, allows to actuate the rotary movement in the cavity 112 of the stem 110 thus making the insertion elements 18 rotate relative to the groove 136. The transmission system is composed of toothed wheels which increase the rotation ratio;

[0070] 3.ratchet system: this transmission system can be inserted either in the case of direct rotation transmission or in the case of transmission via toothed wheels. Its purpose is to allow only one direction of rotation at a time. Also, a ratchet release system 122 may be provided so as to allow rotation in the opposite direction of the system 10, to permit the extraction of the insertion element 18;

[0071] 4. applicator stem guide system: the stem 110 is integral with the terminal wheel of the transmission ratio, thereby making the same number of revolutions as the wheel. The stem 110 is hollow (cavity 112) inside and has grooves 136 which form a helical guide in which the insertion elements 18 can slide. The pitch of the helical grooves 136 coincides with the dimensions of the insertion elements 18, this allows the rotation of the insertion elements 18 within the cavity 112 of the stem 110. The translation of the insertion elements 18 occurs thanks to the presence of a fixed worm screw 138, which is integral with the fixed grip handle 104 of the applicator 100.

[0072] Preferably all embodiments of the applicator 100 according to the present invention may be implemented with an electric motor which generates the rotation of the motion transmission mechanism 108 in an automatic manner, thus actuating electrically, for example by a button or a remote control, the movable drive device, thereby allowing the translation of the system 10 inside the stem 110. The electric motor may have two directions of rotation which can be selected via appropriate buttons so that the surgeon may select whether to implant or extract the insertion elements 18. Such buttons may for example be located on the external surface of the fixed grip handle 104 or may be present on external consoles for remote actuation of the applicator 100.

[0073] A third object of the present invention relates to a kit comprising a system 10 for the repair (suture) of biological tissues, as described above, and an applicator 100 for the insertion of the system 10 into an injured biological tissue in order to repair it (suture it), as described above.

[0074] Advantageously, therefore, the system 10 according to the present invention preferably comprises the insertion elements 18 which are introduced perpendicularly to the tissues to be repaired (sutured) allowing the recruitment of muscle units, and by coupling devices 12 which allow retaining and maintaining the insertion elements 18 in apposition so as to favour the healing of the injured tissue. Such system 10 can be used differently depending on the target tissue on which it is applied; insertion can occur at the site of the lesion or in the distal part of the tissue. The invention replaces or integrates the traditional suturing technique used to approximate tissues in order to obtain their healing. The insertion elements 18 have a tapered geometry and their insertion into the tissue, which takes place by simple rotation and / or translation around an axis perpendicular to that of the lesion, is facilitated by the presence of an acuminate distal end 22. The coupling device 12 allows a firm coupling of the insertion elements 18, giving the tissue-system 10 assembly a solid structural stability. Preferably construction in biocompatible material is provided and possibly resorbable in different times depending on biological needs. The system 10 may become a carrier for the release of drugs or become a scaffold for tissue reconstruction. The invention may be used in traditional open surgery or laparoscopically or even percutaneously. The invention may be used both in the human field and in the veterinary field. The system 10 may be both inserted within injured tissues and removed therefrom.

[0075] The system 10, the applicator 100 and the kit according to the present invention thus provide the following advantages:

[0076] •facilitate insertion into the tissue thanks to the minimal bulk that characterises the insertion elements 18 and the related coupling device 12;

[0077] •allow facilitating the recruitment of muscle bands with progressive penetration of the insertion elements 18 into the target tissue;

[0078] •confer to the tissue-system 10 assembly a solid structural stability thanks to the coupling device 12 of the insertion elements 18 which allows a firm coupling thereof;

[0079] •eliminate problems caused by suture knots, such as tissue deformation at the point corresponding to the knot and failure of anchoring due to rupture of the knot itself;

[0080] •distribute loads uniformly along the tissue lesion thanks to the tapered geometry of the insertion elements 18, recruiting and firmly maintaining the edges of injured tissue close to one amother by means of the innovative coupling device 12, and thus reducing damage to the tissues themselves;

[0081] • ensure vascularisation of the tissue by not obstructing the biological self-repair process and favouring an optimal healing, more stable and in a shorter time. The system 10, the applicator 100 and the kit according to the present invention, thanks to the particular geometry of the insertion elements 18 and to the reduced bulk of the related coupling device 12, allow advantageously to:

[0082] • increase the hold of the suture by off-loading and distributing at a distance from the line itself the forces acting which are the cause of incomplete healing;

[0083] •avoid ischemia which traditional sutures cause at the line itself and are a concomitant cause of delays or non-healing in association with the preceding point;

[0084] •optimise tissue approximation and the maintenance thereof even in presence of high and prolonged acting forces.

[0085] The concomitant elimination of the three causes of failure already previously identified occurs because: a) the exercise of the forces in play is distributed and removed from the margin of the wound; b) the margin of the wound does not cause ischemia by suture threads; c) the approximation of the edges is optimal and is maintained for a long time.

[0086] The positioning of the system 10 according to the present invention is simple, does not require a particular learning curve because it is in fact little or not at all operator-dependent.

[0087] The system 10, the applicator 100 and the kit according to the present invention therefore present the following advantages:

[0088] • the primary result is a reduction of current failures;

[0089] • allow avoiding result variability induced by limited experience of the operator;

[0090] • allow avoiding modification of surgical techniques especially in laparoscopic surgery where sometimes one prefers to avoid closing the parietal defect due to the objective difficulty that this involves with traditional techniques except by resorting to complex and economically very costly systems such as the surgical robot;

[0091] • allow the dissemination of use of a system which even in prevention has wide application and which more than offsets the costs by reason of reduction of complications.

[0092] Advantageously, the system 10 for repair of biological tissues according to the present invention can be used only for repair of soft tissues and not for fixation of bony elements, therefore it is not intended for fixation of prosthetic elements. Advantageously, furthermore, the system 10 according to the present invention may only be adopted for soft tissue approximation, not therefore for the different types of surgical fixation. The system 10 may also preferably be used in a specific configuration and a specific body region; in particular, the system 10 is advantageously used for repair of abdominal hernia in the region of the linea alba, of the rectus abdominis muscle, of the internal, external and transverse oblique muscles; therefore preferably not being adopted in other body regions. In addition, to function correctly, the system 10 must be implanted within the muscle in a direction perpendicular with respect to fibre orientation so that, once closed, both insertion elements 18 are inside the muscle.

[0093] Advantageously, the system 10 according to the present invention comprises a coupling device 12 comprising at least a first element 14 couplable to a second element 16, the system 10 further comprising at least two insertion elements 18 each comprising a proximal end 20 connected or connectable to either said first element 14 or to said second element 16 of the coupling device 12 and an acuminate distal end 22, wherein said at least two insertion elements 18, when in operative configuration, are positioned with 180° rotational symmetry to each other, wherein when the first element 14 is coupled with the second element 16 the coupling device 12 is capable of ensuring a stable but reversible connection between said at least two insertion elements 18. Therefore, only in this manner does the system 10 provide a stable fixation of the repair.

[0094] Advantageously, the system 10 according to the present invention cannot alter the function of a tissue or organ; it is in fact a repair device which allows only closure of injured soft tissues, without causing alterations in the function of the tissue itself.

[0095] Advantageously, the system 10 according to the present invention is intended to be employed with or without the aid of sutures for repair of soft tissues, thus not for placement of meshes.

[0096] Advantageously the device 10 according to the present invention is preferably used precisely at the site of the lesion (directly on the damaged part), not in its vicinity. The system 10 according to the present invention provides, advantageously, a stable positioning of the edges of tissue in order to guide tissue repair. The first and the second elements 14 and 16 couple together, the system 10 thus operates with at least two anchoring elements; a single anchoring element could not permit closure of the lesion site.

[0097] The system 10 according to the present invention may also, advantageously, have a different geometric profile depending on the manufacturing process designated for production of its components (for example the injection moulding technique).

[0098] The system 10 according to the present invention is moreover, advantageously a removable system. Moreover, the material with which the system 10 is made is a biocompatible and / or biodegradable material.

[0099] Advantageously, moreover, the applicator 100 according to the present invention is a tool that works exclusively with the system 10 according to the present invention. It, advantageously, exploits the direct transmission of the movement of the movable drive device 106. The principle of the applicator 100 is advantageously based on the action of the movable drive device 106 which transmits the movement directly to a series of gears.

[0100] Examples

[0101] Some preferred embodiments of the present invention are now reported, provided by way of illustration and not limitation.

[0102] Example 1: Insertion tests of the insertion elements 18 into tissue.

[0103] Thanks to the use of insertion elements 18 in spiral shape comprising acuminate distal ends 22, insertion tests were carried out in a tissue. The aim of these investigations was to verify the feasibility of penetration and recruitment of muscle bands. To this end, cuts of beef meat colloquially known as "Brisket" were used. Figure 20 shows one of the insertion tests of the spiral- shaped insertion elements 18. Example 2: Execution of uniaxial tensile tests

[0104] For the initial validation of the invention, some tensile tests were performed on prototypes of insertion elements 18 manufactured in AIS 152 spring steel. For the design of these prototypes, the following parameters were considered: axial diameter of the prototypes of insertion elements 18, pitch, length of the prototypes of insertion elements 18 and wire diameter. In particular, some parameters were kept constant, length equal to 30 mm and wire diameter equal to 1 mm. As for the other parameters, two values were considered: axial diameter of the prototype equal to 4 mm and 8 mm (D4 and D8), pitch of the helix (of the helix / spring- shaped prototype) equal to 5.5 mm and 8 mm (P5.5 and P8). For the production of the prototypes, a combination of each design parameter was considered, in order to obtain four different types of prototypes. Figure 21 shows the tested prototypes and the meat samples used for analysis. Figure 22 shows the load-displacement curves of one prototype per type.

[0105] Example 3: Prototyping tests of the insertion elements 18 and of the coupling device 12 by 3D printing

[0106] Some 3D printing tests were carried out using an SEA (stereolithographic) printer. In particular, the resin chosen for the production of these prototypes was selected based on its mechanical performance, which had to be similar to that of the final material with which the insertion elements 18 and the coupling devices 12 will be made. This is because, at the preliminary stage, it was hypothesised that such elements would potentially be manufactured from biocompatible and biodegradable material. Figure 23 shows images of the insertion elements 18 and some coupling devices 12 printed using a 3D printer.

[0107] Legend of drawings

[0108] Figure 22:

[0109] SPRINGS MECHANICAL PROPERTIES = PROPRIETA MECCANICHE DELLE MOLLE

[0110] Load [N] = Carico [N] Displacement [mm] = Spostamento [mm]

Claims

CLAIMS1. System (10) for repairing biological tissues comprising a coupling device (12) comprising at least a first element (14) couplable to a second element (16), the system (10) further comprising at least two insertion elements (18) each comprising a proximal end (20) connected or connectable to either said first element (14) or to said second element (16) of the coupling device (12) and an acuminate distal end (22), wherein the at least two insertion elements (18), when they are in an operative configuration, placed one another with 180° rotational symmetry, wherein when the first element (14) is coupled to the second element (16), the coupling device (12) is capable of ensuring a stable but reversible connection between said at least two insertion elements (18).

2. System (10) according to claim 1, wherein the at least two insertion elements (18) have the same shape.

3. System (10) according to claim 1, wherein the at least two insertion elements (18) have different shapes.

4. System (10) according to claim 1, wherein at least one of the at least two insertion elements (18) has a spiral shape.

5. System (10) according to claim 1, wherein at least one of the at least two insertion elements (18) comprises a through cavity (24) positioned longitudinally along part or all of the length of the insertion element (18).

6. System (10) according to any one of claims 1 to 5, wherein the coupling device (12) is selected from: interlocking coupling device (26), screwing coupling device (28), counterrotating motion coupling device (30), adjustable closure coupling device (32), T-closure coupling device (34), bar-closure coupling device (36), suture wire-assisted coupling device (38), adjustable and reversible closing coupling device with guide (40), adjustable, reversible and external closing coupling device (42), adjustable, reversible and comprised in the insertion elements closing coupling device (44).

7. System (10) according to any one of claims 1 to 6, wherein the at least two insertion elements (18) and / or the coupling device (12) are made of biocompatible and biodegradable material, or biocompatible but non-biodegradable material.

8. Applicator (100) for inserting and / or removing the system (10), according to any one of claims 1 to 7, into and / or from an injured biological tissue in order to repair it, comprising a main body (102) in turn comprising: a fixed grip handle (104), a movable drive device (106) mechanically connected to a motion transmission mechanism (108) of the drive device (106), a stem (110) comprising a cavity (112) for housing the system (10) and a translatory mechanism (114), wherein the motion transmitting mechanism (108) of the drive device (106) is further mechanically connected to the translatory mechanism (114) which in turn is connected to the system (10) housed in the cavity (112) of the stem (110) thereby allowing a translatory motion of the system (10) within the cavity (112) of the stem (110).

9. Applicator (100) according to claim 8, wherein the motion transmission mechanism (108) of the drive device (106) comprises a first toothed unit (116) integral with the drive device (106), at least one first toothed wheel (118) couplable with the toothing of said first toothed unit (116), a second toothed wheel (120) couplable with the toothing of said first toothed wheel (118), wherein said second toothed wheel (120) is couplable with the translatory mechanism (114) of the stem (110).

10. Applicator (100) according to claim 9, wherein the at least one first toothed wheel (118) comprises a ratchet mechanism (122) comprising a third toothed wheel (124) integral with, coaxial and parallel to the first toothed wheel (118) and a plurality, preferably three, of spring systems (126) radially positioned around the third toothed wheel (124), wherein each spring system (126) comprises a spring (128) coupled to a lever (130) having a tapered portion, wherein the spring (128) is abutted against the tapered portion of the lever (130) so as to push the tapered portion of the lever (130) against the toothing of the third toothed wheel (124).

11. Applicator (100) according to any one of claims 8 to 10, wherein the applicator (100)is made of polymeric or metallic material or both.

12. Kit comprising a system (10) for repairing biological tissues, accord-ing to any one of claims 1 to 7 and an applicator (100) for inserting the sys-tem (10) into an injured biological tissue in order to repair it, according to any one of claims 8 to 11.

Images