System for treating calcaneal fractures

Abstract

The present disclosure proposes a fixation device (105), of the internal type, for calcaneal fracture osteosynthesis. The fixation device comprises a main fixing screw (205) and a plurality of secondary fixing screws (2101-2106), wherein the main fixing screw is adapted to be inserted in the heel along a longitudinal direction (X) identifying a prevalent extension direction of the foot. The main fixing screw (205) comprises a plurality of insertion holes (2151-2156) adapted to allow the secondary fixing screws (2101-2106) to be inserted through the main fixing screw (205), transversally to the main fixing screw, at respective insertion angles. The present disclosure also proposes an application device (110) adapted to guide the application of the plurality of secondary fixing screws into the main fixing screw of the fixation device, and a reduction device (115) adapted to allow the reduction of calcaneal fracture. The present disclosure further proposes a system (100) per treating of calcaneal fractures comprising the fixation device, the application device, and the reduction device.

Description

[0001] DESCRIPTION

[0002] Title: System for treating calcaneal fractures

[0003] Technical field

[0004] The present disclosure generally relates to the field of orthopedic surgery. In particular, the present disclosure relates to a system and a method for treating calcaneal fractures.

[0005] Background art

[0006] The technological background of the present disclosure will be discussed below. In any case, even where this discussion concerns techniques that can be found in documents, acts and / or artifacts, it is not intended to suggest or acknowledge that such techniques are to be considered part of the state of the art and / or common general knowledge in the field for the purposes of the present disclosure.

[0007] The calcaneus represents one of the main bones of the foot, and calcaneal fractures are among the most complex to treat in the orthopedic field: this is essentially due to anatomical complexities (the calcaneus has an articulated bone structure, with multiple articular surfaces and a three-dimensional shape that is difficult to reconstruct after a fracture), biomechanical requirements (the calcaneus, bearing a large part of the body weight, is essential for push-off and shock absorption movements during walking, so that any alteration of its structure can compromise load distribution and gait mechanics), variety of traumas, and surgical difficulties (the surgical approach may be complicated due to factors such as position, the need to avoid damage to soft tissues, nerves and blood vessels, the need for high precision in order to ensure stability and prevent complications such as malunion and non-union, and the risk of infections).

[0008] The treatment of calcaneal fractures typically provides for a reduction phase, i.e. the separation of the bone fragments to bring them back into their correct anatomical position and the maintenance of the reduction during the subsequent surgical procedure, and an osteosynthesis phase aimed at stabilizing the bone fragments during the healing process, preventing complications and improving foot function after healing.

[0009] In the context of calcaneal fractures, the osteosynthesis phase may provide for the use of one or more osteosynthesis devices, for example external osteosynthesis devices or internal osteosynthesis devices. Examples of internal osteosynthesis devices include plates (metal devices fixed with screws to stabilize complex fractures), Kirschner wires (K-wires) (metal wires inserted through the skin and the bone to keep the fragments in position), and calcaneal nails.

[0010] Internal osteosynthesis devices have some drawbacks: plates, while offering good stability, can cause irritation of the soft tissues and require wide incisions; Kirschner wires, while offering limited or relatively limited invasiveness, provide limited stability; calcaneal nails, while providing good internal stabilization, may be less effective in complex fractures and may be difficult to insert correctly.

[0011] On the other hand, external osteosynthesis devices, although suitable for use in severe cases, are bulky and may lead to cutaneous complications.

[0012] Summary

[0013] A simplified summary of the present disclosure is provided herein in order to furnish a basic understanding thereof; however, the sole purpose of this summary is to introduce certain concepts of the disclosure in a simplified form as a prelude to the more detailed description that follows, and it is not to be construed as identifying its essential elements nor as delimiting the scope thereof.

[0014] In general terms, the present disclosure is based on the idea of a fixation device (of the internal type) comprising a main fixing screw and a plurality of secondary fixing screws configured to be inserted into the main fixing screw at respective insertion angles.

[0015] One or more aspects of the present disclosure are set out in the independent claims, and advantageous features thereof are set out in the dependent claims, with the text of all claims being incorporated herein verbatim by reference (with any advantageous feature provided with reference to any specific aspect applying mutatis mutandis to every other aspect).

[0016] Particularly, an aspect of the present disclosure provides a fixation device, of the internal type, for calcaneal fracture osteosynthesis.

[0017] The fixation device comprises a main fixing screw and a plurality of (z.e., two or more) secondary fixing screws. The main fixing screw is adapted to be inserted in the heel along a longitudinal direction identifying a prevalent extension direction of the foot.

[0018] The main fixing screw comprises a plurality of insertion holes adapted to allow the secondary fixing screws to be inserted through the main fixing screw, transversally to the main fixing screw, at respective insertion angles.

[0019] According to an embodiment, on a lateral plane identified by the longitudinal direction and by a vertical direction orthogonal to the longitudinal direction, with respect to the vertical direction:

[0020] - the insertion angle of a first and of a second insertion holes of said plurality of insertion holes is equal to 10°;

[0021] - the insertion angle of a third insertion hole of said plurality of insertion holes is equal to 0°;

[0022] - the insertion angle of a fourth insertion hole of said plurality of insertion holes is equal to 15-20°;

[0023] - the insertion angle of a fifth insertion hole of said plurality of insertion holes is equal to 25-30°.

[0024] According to an embodiment, on a front plane identified by the vertical direction and by a transverse direction orthogonal to the longitudinal direction and to the vertical direction, with respect to the vertical direction:

[0025] - the insertion angle of the first, second, and third insertion holes is equal to 0°;

[0026] - the insertion angle of the fourth insertion hole is equal to 25-30°;

[0027] - the insertion angle of the fifth insertion hole is equal to 30-35°;

[0028] - the insertion angle of a sixth insertion hole of said plurality of insertion holes is equal to 90°.

[0029] According to an embodiment, on a top plane identified by the longitudinal direction and by the transverse direction, with respect to the transverse direction:

[0030] - the insertion angle of the fourth insertion hole is equal to 25°;

[0031] - the insertion angle of the fifth insertion hole is equal to 30°;

[0032] - the insertion angle of the sixth insertion hole is equal to 10°.

[0033] According to an embodiment, the main fixing screw comprises coupling portions configured to allow the coupling, to the main fixing screw, of an application device adapted to guide the application of the plurality of secondary fixing screws into the main fixing screw.

[0034] Another aspect of the present disclosure provides an application device adapted to the application of the secondary fixing screws into the main fixing screw of the fixation device.

[0035] The application device comprises a first arm adapted to the coupling of the application device to the main fixing screw.

[0036] The application device comprises a plurality of second arms comprising a plurality of guiding holes adapted to guide the application of the secondary fixing screws to the main fixing screw. When the application device is coupled to the main fixing screw the guiding holes are aligned to the insertion holes.

[0037] The application device comprises a clamping member adapted to clamp the first arm to the main fixing screw to secure and keep securely fastened the application device to the main fixing screw during the application of the secondary fixing screws to the main fixing screw.

[0038] According to an embodiment, the first arm comprises, at a first end thereof that, in use, faces the main fixing screw, one or more fastening elements for centering and fastening the application device to the main fixing screw.

[0039] According to an embodiment, the first arm comprises a cavity extending from the first end of the first arm to a second end of the first arm opposite to the first end. Said cavity is adapted to receive the clamping member.

[0040] According to an embodiment, said plurality of second arms is made of a radiolucent material, for example carbon or carbon composite.

[0041] A further aspect of the present disclosure provides a reduction device adapted to allow the reduction of the calcaneal fracture.

[0042] According to an embodiment, the reduction device comprises a main structure, adapted to be inserted into the heel, fixation components adapted to be inserted in the heel, an adjusting mechanism connected to the main structure, and a connection mechanism adapted to connect the adjusting mechanism to the fixation components.

[0043] According to an embodiment, said connection mechanism comprises one or more connection elements made of a radiolucent material, for example carbon o carbon composite.

[0044] A further aspect of the present disclosure provides a system for treating the calcaneal fractures comprising the fixation device and the application device.

[0045] A further aspect of the present disclosure provides a system per treating the calcaneal fractures comprising the fixation device, the application device and the reduction device.

[0046] A further aspect of the present disclosure provides a method for treating calcaneal fractures. The method comprises: providing the fixation device; forming a calcaneal channel. According to an embodiment, this may be achieved by making an incision in the skin at the calcaneus, inserting a guide wire through the point of incision, introducing a Kirschner wire at the point of incision and advancing it along the calcaneus using the guide wire as a reference, and actuating a cannulated drill along the Kirschner wire; inserting and screwing the main fixing screw of the fixation device into the calcaneal channel; providing the application device; coupling the application device to the main fixing screw through the first arm and the clamping member; inserting the secondary fixing screws into the insertion holes of the main fixing screw through the plurality of guiding holes of the plurality of second arms of the application device; decoupling the application device from the main fixing screw.

[0047] Brief description of the figures

[0048] The present disclosure, as well as further features and the corresponding advantages, will be better understood with reference to the following detailed description, provided purely by way of illustration and not limitation, to be read in conjunction with the accompanying figures (in which, for simplicity, corresponding elements are indicated with identical or similar references and their explanation is not repeated, and the name of each entity is generally used to indicate both its type and its attributes, such as value, content, and representation). In particular:

[0049] Fig.l schematically shows a system for treating calcaneal fractures according to embodiments of the present disclosure; Figs.2A-2D schematically show a fixation device according to embodiments of the present disclosure;

[0050] Figs.3A-3C schematically show an application device according to embodiments of the present disclosure, and

[0051] Figs.4A and 4B schematically show a reduction device according to embodiments of the present disclosure.

[0052] Detailed description of exemplary embodiments of the present disclosure

[0053] Fig.l schematically shows a system for treating calcaneal fractures (in the following, for the sake of brevity, referred to as PCS ("Provenza Calcaneo System’"') system) 100 according to embodiments of the present disclosure.

[0054] In the following, the terms including, comprising, having, containing, involving, and the like should be interpreted in an open and non-exhaustive sense (i.e., not limited to the recited elements); the terms based on, dependent on, in accordance with, according to, as a function of, and the like should be interpreted as indicating a non-exclusive relationship (i.e., with possible additional variables involved); the term a / an should be understood as meaning one or more elements (unless expressly stated otherwise); and the term means for (or any functional formulation) should be understood as encompassing any structure suitable or configured to perform the relevant function.

[0055] The PCS system 100 comprises a fixation device 105 adapted to fix the calcaneal bone fragments (osteosynthesis), an application device 110 adapted to allow (and guide) the application of components of the fixation device 105, and a reduction device 115 adapted to allow the reduction of the fracture (for example, before the application of the fixation device 105). As will be apparent from the following description, the PCS system 100 introduces significant improvements in terms of stability, invasiveness, and adaptability, and represents a significant progress in the field of orthopedic surgery, improving the clinical outcomes for patients with calcaneal fractures.

[0056] With reference to Figs.2A-2D, they schematically show the fixation device 105 according to embodiments of the present disclosure. Particularly, Fig.2A shows a perspective view of the fixation device 105 in disassembled configuration, whereas Figs.2B-2D show views in orthogonal projection of the fixation device 105 in assembled configuration. More specifically, with reference to the three mutually orthogonal spatial directions X.Y,Z, wherein X is the longitudinal direction (and identifies, for example, the prevalent extension direction of the foot, namely its length), Y is the transversal direction (and identifies, for example, the width of the foot), and Z is the vertical direction, Fig.2B shows the fixation device 105 in a side view (X-Z plane, also referred to as lateral plane), Fig.2C shows the fixation device 105 in top or plan view (X-Y plane, also referred to as top plane), and Fig.2D shows the fixation device 105 in a front view (Y-Z plane, also referred to as front plane).

[0057] The fixation device 105 is based on screws, and particularly it comprises a main fixing screw 205 adapted to be inserted into the heel along the longitudinal direction X, and a plurality of (for example, 6) secondary fixing screws 2101,2102,2103,2104,2105,2106 (in the following, for the sake of brevity, 210i-210e), for example having smaller size with respect to the main fixing screw 205, adapted to be inserted transversally to the main fixing screw 205 (at predefined insertion angles, as discussed in the following), passing through the main fixing screw 205 and the bone fragments, securing them firmly in place. For the purposes of the present disclosure, by transversal insertion of a secondary fixing screw 210i-210e into the main fixing screw 205 it is meant an insertion such that the secondary fixing screw 210i-210e passes through the main fixing screw 205 in a non-orthogonal manner (namely, in oblique manner) or in orthogonal manner, depending on the respective insertion angle.

[0058] The representations of the main fixing screw 205 and of the secondary fixing screws 210i-210e are used for illustrative purposes only and should not be understood as detailed reproductions of specific elements and / or features. Particularly, shape, size, and relative size of the main fixing screw 205 and of the secondary fixing screws 210i- 210e or of parts thereof, could differ from those exemplary illustrated.

[0059] Without loss of generality, the insertion of the main fixing screw 205 into the heel may take place according to one or more known procedures. By way of nonlimiting example only, the insertion of the main fixing screw 205 into the heel may comprise the following steps (or a subset thereof): formation of a minor incision in the skin at the level of the heel, insertion of a guide wire through the incision point until reaching the desired position in the heel, introduction of a Kirschner wire (K-wire) into the incision point and advancement thereof along the heel (using the guide wire as a reference, following the trajectory established by it), operation of a cannulated drill along the K-wire to create a calcaneal channel, removal of the cannulated drill, insertion of the main fixing screw 205 into the calcaneal channel (sliding it in a guided manner along the K-wire, if not yet removed, or in a free / unguided manner if the K- wire has been removed), and screwing of the main fixing screw 205 until the desired position is achieved.

[0060] The main fixing screw 205 is preferably made of titanium or surgical stainless steel (for example, so as to confer high strength, corrosion resistance, and biocompatibility)

[0061] The main fixing screw 205 comprises a head (visible in Fig.2D) whose drive, not limitative for the purposes of the present disclosure, may be advantageously chosen according to specific design parameters (for example, torque, ease of use, slip resistance, type of driving / unscrewing instrument). Without loss of generality, the head of the main fixing screw 205 may have a slotted drive, a Phillips drive, a Torx drive, a hex drive, or, as visible in Fig.2D, a dedicated drive (namely, a non-standard drive). In the exemplary (and non-limiting) considered embodiment, the dedicated drive of the head of the main fixing screw 205 is defined by a plurality of (for example, four) recesses (or grooves) 205SA (visible in Fig.2D) arranged along a head edge, for example at four equally spaced points.

[0062] The dedicated drive of the head of the main fixing screw 205 defined by such configuration of the recesses 205SA is advantageous in that the recesses 205SA may also act as reference / alignment elements and as engagement seat for the coupling of the application device 110 (as better discussed in the following).

[0063] Without loss of generality, the screwing of the main fixing screw 205 may be achieved through a dedicated screwdriver (not shown), for example a cannulated screwdriver provided with engagement elements adapted to fit into the recesses 205SA. Anyway, the tool used for screwing the main fixing screw 205 is not limitative for the present disclosure. In this respect, the main fixing screw 205 whose head has the dedicated drive defined by the configuration of the recesses 205SA discussed above may also be handled / rotated (for screwing the main fixing screw 205) through a conventional screwdriver (not shown), for example through engagement at least partial of one or more portions of the tip of the conventional screwdriver in one or more of the recesses 205SA.

[0064] The main fixing screw 205 comprises a threaded body (as visible in Fig.2A), preferably a body provided with metric threading (which, due to its holding characteristics, uniform force distribution, insertion precision, stability, durability, and resistance to removal, is particularly suitable for dense bones such as the calcaneus). Although not shown, the main fixing screw 205 may comprise a self-tapping tip (for example, so as to allow the formation of the tread together with the screwing).

[0065] In the exemplary (and non-limiting) illustrated embodiment, the head and the body of the main fixing screw 205 have same (or substantially same) width or diameter: this advantageously causes a lower bone footprint, a reduced risk of soft tissue irritation, improved force distribution, facilitation of bone healing, and better aesthetics in visible / exposed areas.

[0066] The main fixing screw 205 comprises coupling portions adapted to allow the coupling of the application device 110 to the main fixing screw 205 (the coupling portions being for example adapted to interact with corresponding coupling means of the application device 110, as discussed in the following).

[0067] In the exemplary considered embodiment, the coupling portions comprise an engagement seat adapted to receive one or more engaging elements of the application device 110 for the engagement of the application device 110 to the main fixing screw 205 (the engaging elements being discussed in the following), and a clamping seat adapted to receive one or more clamping members of the application device 110 for clamping the application device 110 to the main fixing screw 205 (the clamping members being discussed in the following).

[0068] In the exemplary considered embodiment, the engagement seat is formed in the head of the main fixing screw 205, and comprises the recesses 205SA that define or delimit the drive (in the example at issue, the dedicated drive) of the head of the main fixing screw 205. In alternative embodiments, not shown, the engagement seat is formed by one or more dedicated recesses (namely, one or more additional recesses being additional with respect to the recesses 205SA that define or delimit the drive of the head of the main fixing screw 205).

[0069] In the exemplary considered embodiment, the clamping seat is formed in the head of the main fixing screw 205, and comprises a threaded blind hole (or countersink) (which is for example adapted to receive a clamping member in the form of a threaded screw or threaded bolt). Such clamping seat is denoted in Fig.2D by the number reference 205ss, and is preferably arranged centrally (or substantially centrally) with respect to the head of the main fixing screw 205 (such clamping seat 205ss being for example delimitated by the edge of the head of the main fixing screw 205 where the recesses 205SA are formed). In alternative embodiments, not shown, the clamping seat 205ss comprises an unthreaded hole and / or a hole with appropriately shaped walls adapted to provide a form-fitting connection (for example, interlocking) and / or a force connection (for example, friction) with the clamping member(s) of the application device 110. For clarity in illustration, the clamping seat 205ss is made visible also in Figs.2B and 2C (in such figures, the main fixing screw 205, is to be understood as depicted, in correspondence of the clamping seat 205ss, through a transparent view).

[0070] For the sake of completeness, Fig.2D also shows a central through-hole, denoted by the number reference 205SG, adapted to the passage of the K-Wire through it (so as to allow, as mentioned before, the insertion of the main fixing screw 205 into the calcaneal channel by guided sliding of the main fixing screw 205 on the K-Wire).

[0071] In the exemplary and non-limiting considered embodiment, the secondary fixing screws 2101-2106 comprise surgical screws identical to each other, namely with same shape and size. In alternative embodiments, not shown, it is possible to provide secondary fixing screws having different shapes and size, for example depending on the application position.

[0072] Each secondary fixing screw 210i-210e (or at least a subset of the secondary fixing screws 210i-210e) is preferably made in titanium or in surgical stainless steel (for example, so as to confer high strength, corrosion resistance, and biocompatibility). Additionally, or alternatively, each secondary fixing screw 2101-2106 (or at least a subset of the secondary fixing screws 210i-210e) may comprise bioabsorbable polymeric materials.

[0073] Each secondary fixing screw 210i-210e (or at least a subset of the secondary fixing screws 210i-210e) comprises a head (visible in Fig.2B for the secondary fixing screw 210e, and in Fig.2C for the secondary fixing screws 2101,2101) whose drive, not limitative for the purposes of the present disclosure, may advantageously be selected according to specific design parameters (for example, clamping torque, ease of use, slip resistance, type of fastening / unfastening tool). Without loss of generality, the head of each secondary fixing screw 2101-2106 (or of at least a subset of the secondary fixing screws 210i-210e) may have a slotted drive, a Phillips drive, a hexagon drive, a Torx drive or, according to a preferred (and not limitative) embodiment, a Stardrive® drive (visible in Figs.2B and 2C).

[0074] In the exemplary (and non-limiting) considered embodiment, each secondary fixing screw 210i-210e is a “headless” screw, namely a screw whose head is not protruding with respect to its body (which means that the screw is substantially cylindrical and has no top part that protrudes from the surface on which it is screwed), this determines integration of the secondary fixing screw 2101-2106 with the surface on which it is screwed, and a lower bulk within the bones.

[0075] In the exemplary (and non-limiting) considered embodiment, each secondary fixing screw 210i-210e is a “headless” screw whose head has an external thread. Such external thread advantageously provides a secure grip in the bone, resulting in an anchoring action (the external thread creates a mechanical interaction with the bone tissue, forming a stable anchor), as well as stability and support (the external thread enhances the screw’s resistance to torsion, traction, and compression forces, which is essential for fracture stabilization).

[0076] Each secondary fixing screw 2101-2106 (or at least a subset of the secondary fixing screws 210i-210e) comprises a threaded body (as visible in Fig.2A), preferably a body having a metric thread (which, for its characteristics of holding, uniform force distribution, insertion accuracy, stability, durability, and resistance to removal, it is particularly suitable for dense bones such as the calcaneus). Although not shown, each secondary fixing screw 210i-210e (or at least a subset of the secondary fixing screws 210i-210e) comprises a self-drilling tip (for example, so as to allow bone penetration without pre-drilling) and / or a self-tapping tip (for example, so as to allow the creation of the thread while screwing).

[0077] As visible in Fig.2A, the main fixing screw 205 comprises a plurality of insertion holes, particularly insertion through-holes, 2151,2152, 2153,2151, 215s, 215e (in the following, for the sake of brevity, 215i-215e) adapted to allow the insertion of the secondary fixing screws 2101-2106 into the main fixing screw 205 at specific insertion angles, stabilizing the surrounding bone fragments and ensuring multidirectional fixation. In the exemplary and non-limiting considered ad illustrated embodiment, the number of insertion holes 215i-215e is equal to the number of secondary fixing screws 210i-210e, with each insertion hole 215i-215e that is positioned, shaped, and sized for receiving a secondary fixing screw 210i-210e at a respective insertion angle. Anyway, the possibility is not excluded, for the surgeon, of using a subset of the secondary fixing screws 2101-2106, and hence a subset of the insertion holes 215i-215e, for example so as to allow to the surgeon to select or exclude one or more insertion angles and / or one or more positions based on a peculiarity of the fracture. For same reasons, in alternative embodiments, not shown, the number of insertion holes may be greater than the number of secondary fixing screws.

[0078] The values, discussed below, of the insertion angles (defined by the insertion holes 2151-2156 and, hence, by the secondary fixing screws 2101-2106 inserted into them) have been recognized by the Applicant as particularly advantageous as they can be applied to a high number fracture types (at least equal to 80% of the totality of fractures) and to a wide morphological and / or anatomical variety of feet. Anyway, the values of the insertion angles are to be construed as purely exemplary: in fact, according to the Applicant, due to manufacturing tolerances of the secondary fixing screws 2101-2106 and / or of the insertion holes 215i-215e, manufacturing tolerances that may be desired (so as to allow to the surgeon a certain degree of adjustment based on specific conditions of the fracture) or undesired (for example, intrinsic to the production processes), such values of the insertion angles may deviate by ±10-15° from the discussed values without substantial loss of effectiveness - for this reason, each of the values of the insertion angles discussed below is to be construed variable in a range of ±10-15°. Moreover, each range of numerical values should be understood as expressly specifying any possible number along the continuum within the range (including its endpoints).

[0079] By insertion angle it is intended the inclination or orientation of the insertion hole 2151-2156 (and of the secondary fixing screw 2101-2106 inserted into it) with respect to the mutually orthogonal planes X-Y, Y-Z and X-Z.

[0080] The insertion angle of the insertion hole 215i (and of the secondary fixing screw 210i inserted into it) is, on the (lateral) plane X-Z, equal to 10° with respect to the vertical direction Z (as visible in Fig.2B), and is preferably equal to 0°, on the (front) plane Y-Z with respect to the vertical direction Z (as visible in Fig.2D). The secondary fixing screw 210i inserted into the insertion hole 215i is also visible in Fig.2C (particularly, due to the used view plane, in such figure only the head of the secondary fixing screw 210i is visible) and in Fig.2D (particularly, due to the used view plane, in such figure no inclination of the secondary fixing screw 210i is visible).

[0081] As visible in Figs.2B and 2C, the secondary fixing screw 210i is arranged, along the longitudinal direction X, properly spaced apart from the head of the main fixing screw 205: such distance is due to the presence of the clamping seat 205ss (and particularly to the depth, specifically the extent along the longitudinal direction X, of the threaded blind hole (or countersink) that defines the clamping seat 205ss). In general, the distance, along the longitudinal direction X, between the secondary fixing screw 210i and the head of the main fixing screw 205 may be selected according to geometry and / or size of the clamping seat 205ss, and such as to satisfy a proper requirement of minimum distance that prevents mechanical interferences between the secondary fixing screw 210i and the clamping member received in the clamping seat 205ss.

[0082] The insertion angle of the insertion hole 2152 (and of the secondary fixing screw 2102 inserted into it) is, on the (lateral) plane X-Z, equal to 10° with respect to the vertical direction Z (as visible in Fig.2B), and is preferably equal to 0° on the (front) plane Y-Z with respect to the vertical direction Z. The secondary fixing screw 2102 inserted in the insertion hole 2152 is also visible in Fig.2C (particularly, due to the used view plane, in such figure only the head of the secondary fixing screw 21(h is visible), whereas it is not visible in Fig.2D (in that, due to the used view plane, the secondary fixing screw 21(h is completely covered by the secondary fixing screw 210i in front of it and having same orientation).

[0083] The insertion angle of the insertion hole 2153 (and of the secondary fixing screw 21(h inserted into it) is, on the (lateral) plane X-Z, equal to 0° with respect to the vertical direction Z (as visible in Fig.2B), and is preferably equal to 0°, on the (front) plane Y-Z with respect to the vertical direction Z. The secondary fixing screw 21(h inserted in the insertion hole 2153 is also visible in Figs.2C and 2D, according to respective view planes: particularly, in Fig.2C only the tip of the secondary fixing screw 21(h is visible, and in Fig.2D only the head of the secondary fixing screw 21(h is visible, being the latter (slightly) lager than (and hence only partially covered by) the tips of the secondary fixing screws 2101,2102 in front of it.

[0084] The insertion angle of the insertion hole 2154 (and of the secondary fixing screw 2104 inserted into it) is, on the (lateral) plane X-Z, equal to 15-20° with respect to the vertical direction Z (as visible in Fig.2B), is preferably equal to 25°, on the (top) plane X-Y, with respect to the transversal direction Y (as visible in Fig.2C), and is preferably equal to 25-30°, with respect to the (front) plane Y-Z, with respect to the vertical direction Z (as visible in Fig.2D).

[0085] The insertion angle of the insertion hole 215s (and of the secondary fixing screw 210s inserted into it) is, on the (lateral) plane X-Z, equal to 25-30° with respect to the vertical direction Z (as visible in Fig.2B), is preferably equal to 30°, on the (top) plane X-Y, with respect to the transversal direction Y (as visible in Fig.2C), and is preferably equal to 30-35°, on the (front) plane Y-Z, with respect to the vertical direction Z. The secondary fixing screw 210s inserted in the insertion hole 215s is not visible in Fig.2D in that, due to the used view plane, the secondary fixing screw 210s is completely covered by the secondary fixing screw 2104 in front of it and having same orientation on the plane Y-Z.

[0086] The insertion angle of the insertion hole 215e (and of the secondary fixing screw 2106 inserted into it) is, on the (top) plane X-Y, equal to 10° with respect to the transversal direction Y (as visible in Fig.2C), and is preferably equal to 90°, on the (front) plane Y-Z, with respect to the vertical direction Z (as visible in Fig.2D). The secondary fixing screw 210e inserted in the insertion hole 215e is also visible in Fig.2B: particularly, due to the used view plane, in such figure only the head of the secondary fixing screw 210e is visible.

[0087] The fixation device 105 provides improved stability (the presence of a main fixing screw and of secondary fixing screws inserted in it in an angled manner offers a multidirectional stability (improving the stabilization of bone fragments and reducing the risk of displacement), is minimally invasive (unlike known solutions such as plates and external fixators, the fixation device 105 requires only small incisions and has a reduced impact on soft tissues), reduced risk of skin complications, and ease and speed of application (the fixation device 105 is designed for an easy and quick application, particularly in association with the application system 110, reducing the operative times and the associated risks).

[0088] The fixation device 105, due to its peculiar features discussed above, may form a separate and independent aspect of the present disclosure.

[0089] With reference to Figs.3A and 3B, they schematically show the application device 110 (in disassembled configuration) according to embodiments of the present disclosure. Particularly, Fig.3A shows a perspective view of the application device 110, whereas Fig.3B shows a plan view of the application device 110 (on the plane X- Y). For clarity, Fig.3A also shows (through a dashed line) a rear portion of the foot of the patient, the main fixing screw 205 inserted into it, and the secondary fixing screws 2101-2106 to be applied to the main fixing screw 205 by means of the application device 110.

[0090] The application device 110 comprises a central arm 305 adapted to the coupling of the application device 110 to the main fixing screw 205, a plurality of (for example, two) lateral arms 310T,310L, provided with guiding holes, adapted to guide the application of the secondary fixing screws 210i-210e to the main fixing screw 205, and a clamping member (for example, an at least partially threaded bolt) SX adapted to be received (for example, screwed) in the clamping seat 205ss of the main fixing screw 205 to secure (and keep securely fastened) the application device 110 to the main fixing screw 205 during the application of the secondary fixing screws 210i-210e to the main fixing screw 205. According to an embodiment, the clamping member SX comprises a cannulated clamping member, which is for example adapted to slide on the guide wire inserted in the heel (thus obtaining a guided insertion of the clamping member SX in the clamping seat 205ss).

[0091] The representations of the central arm 305, of the lateral arms 310T,310L, and of the clamping member SX are used for illustrative purposes only and should not be understood as detailed reproductions of elements and / or specific features. Particularly, shape, size and relative size of the central arm 305, of the lateral arms 310T,310L, and of the clamping member SX, or of parts thereof, could differ from those exemplary illustrated.

[0092] As visible in Figs.3A and 3B, the central arm 305 has a substantially longitudinal development, namely along the longitudinal direction X.

[0093] The central arm 305 preferably comprises, at an operative end thereof that, in use, faces the main fixing screw 205, one or more engaging elements 305A for the centering and engagement of the application device 110 to the main fixing screw 205. In the exemplary illustrated embodiment, the engaging elements 305A comprise one or more (for example, four) protrusions or teeth adapted to be received in the engagement seat 205SA of the head of the main fixing screw 205. Without loss of generality, the engaging elements 305A are adapted to be received in the engagement seat 205SA without friction (in this case such engaging elements 305A may predominantly have, although not exclusively, a centering or alignment function of the application device 110 with respect to the main fixing screw 205) or with friction (in this case such engaging elements 305A may also have a retention function, at least partial, of the application device 110 to the main fixing screw 205, so as to promote the subsequent clamping operation through the clamping member SX). In the exemplary (and non-limiting) considered embodiment wherein the engagement seat 205SA comprises four recesses, the engaging elements 305A comprise four protrusions or teeth each one adapted to be received in a respective recess.

[0094] The central arm 305 preferably comprises a cavity 305c adapted to receive the clamping member SX. Such cavity 305c, having a prevalent longitudinal development, is a through-cavity extending from the operative end of the central arm 305 to the free end opposite thereto (in other words, the cavity 305c extends between the operative end of the central arm 305 and the free end, opening on them). Particularly, the cavity 305c opens on the free end of the central arm 305 for the insertion of the clamping member SX, and on the operative end for facing (in an aligned manner) the clamping seat 205ss of the main fixing screw 205; in this way, the insertion (and, if provided, the screwing) of the clamping member SX into the cavity 305c and the clamping seat 205ss determines the stable coupling of the application device 110 to the main fixing screw 205.

[0095] The fastening elements 305A, the cavity 305c, and the clamping member SX identify the above-cited coupling means of the application device 110 adapted to interact with the coupling portions (namely, the engagement seat 205SA and the clamping seat 205ss) of the main fixing screw 205. In the exemplary (and non-limiting) illustrated embodiment, the central arm 305 of the application device 110 and the main fixing screw 205 of the fixation device 105 (or at least the respective portions that, in use, namely at the coupling between the fixation device 105 and the application device 110, interact / face to each other) have a dimensional correspondence, particularly same (or substantially same) width or diameter: this advantageously determined a precise and uniform coupling. This dimensional correspondence not only makes the assembly (or coupling) easy, but also contributes to create a fluid interface (continuous coupling) between the application device 110 and the fixation device 105, minimizing the discontinuity or gaps that could compromise the functionalities of the system. Moreover, such continuous coupling improves the structural stability of the assembling (the absence of joints or discontinuities reduces the risk of unwanted movements between the components, minimizing wear and prolonging the service life of the assembly, optimizes force transmission (which is distributed evenly throughout the system, reducing concentrated stress points that could lead to failure or deformation), and improves the aesthetics of the final product (the visual continuity between the two components provides a more pleasing and professional appearance).

[0096] In the exemplary considered embodiment, the application device 110 comprises two lateral arms 310T,310L. Although the use of two lateral arms is particularly advantageous in terms of visibility and maneuverability for the surgeon (in that the resulting structure has a reduced or relatively reduced volume), alternative embodiments (not shown) may provide for the use of further lateral arms.

[0097] In the exemplary considered embodiment, the lateral arms 310T,310L have a prevalently longitudinal development, namely along the longitudinal direction X (with the lateral arm 310L that, as visible in the figure, has end portions curved in different directions and on different planes based on the orientation of the corresponding guiding holes).

[0098] In the exemplary considered embodiment, the lateral arms 310T,310L are offset relative to each other along the vertical direction Z, and comprise an upper lateral arm 310T, positioned higher (along the vertical direction Z) with respect the central arm 305, and a lower lateral arm 310L position lower (along the vertical direction Z) with respect al central arm 305. In the present disclosure, the upper lateral arm 310T and the lower lateral arm 310L are generically denoted as lateral arms 310T,310L, when distinguishing between the upper lateral arm 310T and the lower lateral arm 310L is not relevant for the purposes of the discussed features.

[0099] As mentioned before, the lateral arms 310T,310L (or, in general, the application device 110) comprise a plurality of guiding holes 3151,3152, 3153, 3154, 315s, 315e (in the following, for the sake of brevity, 315i-315e) adapted to guide the application of the secondary fixing screws 210i-210e to the main fixing screw 205.

[0100] Each lateral arm 310T,310L comprises respective guiding holes, which, when the application device 305 is coupled to the main fixing screw 205, are aligned to the insertion holes 215i-215e. Particularly, in the exemplary considered embodiment, the upper lateral arm 310T comprises guiding holes 3151,3152 that, when the application device 110 is coupled to the main fixing screw 205, are aligned to the insertion holes 2151,2152, respectively, and the lower lateral arm 310L comprises guiding holes 3153,3154,315s,3156 that, when the application device 110 is coupled to the main fixing screw 205, are aligned to the insertion holes 2153, 2154, 215s, 215e, respectively. Without loss of generality, each lateral arm 310T,310L may comprise any number of guiding holes. In embodiments wherein the application device 110 comprises a higher number of lateral arms, each lateral arm may comprise a respective subset of the guiding holes (at most, a single guiding hole for each lateral arm).

[0101] The lateral arms 310T,310L are preferably made of a radiolucent material, for example carbon o carbon composite: this determines, during real-time radiographic imaging procedures (such as fluoroscopy), high-quality images with a substantial reduction of interference and artifacts: the surgeon therefore has a clear view of the anatomical structures, resulting in benefits in terms of the safety and effectiveness of the procedure of application of the secondary fixing screws 2101-2106.

[0102] The central arm 305 is preferably made of steel, for example, so as to confer high strength and durability properties. Anyway, the central arm 305 can be made of any material deemed adapted to the purpose.

[0103] The application device 110 comprises one or more interconnection elements connecting the lateral arms 310T,310L to the central arm 305. In the exemplary illustrated embodiment, each lateral arm 310T,310L is connected to the central arm 305 through a respective interconnection element 320T,320L, the interconnection elements 320T,320L being for example formed in a single piece construction with the central arm 305.

[0104] The interconnection elements 320T,320L are advantageously arranged substantially transversally to the central arm 305 and to the lateral arms 310T,310L, SO as to act as grip area (or handle) of the application device 110: this allows the surgeon to hold the application device 110 securely and comfortably during the transport and assembly phases to the main fixing screw 205.

[0105] Without loss of generality, after the fixation device 105 and the application device 110 have been assembled (or coupled) to each other, the insertion of the secondary fixing screws 210i-210e in the heel through the main fixing screw 205 may be performed based on one or more procedures deemed adapted to the purpose and / or with one or more tools deemed adapted to the purpose. By way of non-limiting example only, the insertion of the secondary fixing screws 210i-210e in the heel may comprise the following steps (or a subset thereof), to be performed for each pair of insertion holes 215i-215e and corresponding guiding holes 315i-315e (namely, for the insertion hole 215i / guiding hole 315i pair, for the insertion hole 2152 / guiding hole 3152 pair, for the insertion hole 2153 / guiding hole 3153 pair, for the insertion hole 2154 / guiding hole 3154 pair, for the insertion hole 215s / guiding hole 315s pair, and for the insertion hole 215e / guiding hole 315e pair): insertion of a first cannula (not shown) through the insertion hole 215i-215e / guiding hole 315i-315e pair, bone perforation through an orthopedic drill (not shown) the tip of which is inserted in the first cannula and is guided by it, removal of the drill and of the first cannula, insertion of a second cannula (not shown) with an inner diameter higher than the inner diameter of the first cannula in the insertion hole 215i-215e / guiding hole 315i-315e pair, insertion of the secondary fixing screw 2101-2106 through the second cannula, and screwing of the secondary fixing screw 210i-210e (which screwing that is thus guided by the second cannula) through the previously made perforation until reaching the desired position.

[0106] The application device 110, due to its peculiar features exposed above, may form a separate and independent aspect of the present disclosure.

[0107] With reference to Figs.4A and 4B, they schematically show the reduction device 115 according to embodiments of the present disclosure. More particularly, Fig.4A shows the reduction device 115 in a top view (namely, on the plane X-Y) and Fig.4B shows the reduction device 115 in a lateral view (namely, on the plane X-Z).

[0108] The reduction device 115 is adapted to allow the reduction of the fracture, namely the separation (distraction) or compression of the bone fragments to restore them to their correct anatomical position and the maintenance of the reduction during the surgical procedure (particularly, improving visibility and access to the fractured area during the application of the fixation device 105).

[0109] In the exemplary (and non-limiting) considered embodiment, the reduction device 115 comprises a distractor device. Without loss of generality, the reduction device 115 comprises an external distractor device (as exemplary shown and discussed in the present disclosure).

[0110] The reduction device 115 comprises a main structure, fixation components (for example, screws, K-wires or pins), not shown, adapted to be inserted in the heel, an adjusting mechanism connected to the main structure, and a connection mechanism adapted to connect the adjusting mechanism to the fixation components: after having inserted the fixation components in the heel (at the end of the fracture) and connected the adjusting mechanism to the fixation components through the connection mechanism, the surgeon may, through the adjusting mechanism, perform a fine control of the position and orientation of the bone (for example, for distracting or compressing the bone fragments); after the desired alignment has been obtained, the fixation device 105 may be applied for bone stabilization (as discussed below).

[0111] In the exemplary considered embodiment, the main structure comprises a threaded rod 405, for example cylindrical. The threaded rod 405, having a prevalently longitudinal development, is made of a high-strength material, for example steel. As will be apparent from the following description, the threads of the threaded rod 405 allow the sliding and the locking of the adjusting mechanism. In the exemplary considered embodiment, the threads of the threaded rod 405 extend for substantially all the length of the threaded rod 405, although this should not be construed limitatively.

[0112] In the exemplary considered embodiment, the adjusting mechanism comprises two or more sliding elements 410 adapted to slide along the threaded rod 405. Each sliding element 410 preferably has a central through hole (not visible in the) that allows its sliding along the threaded rod 405, the adjustment of the distance between the sliding elements 410 determining the desired alignment of the bone fragments.

[0113] In the exemplary considered embodiment, the adjusting mechanism comprises two or more locking elements 415 adapted to lock the sliding elements 410 in the desired position along the threaded rod 405. Without loss of generality, the locking elements 415 comprise screwing locking elements, for example locking nuts (as exemplary illustrated). In alternative embodiments, not shown, the locking elements 415 may comprise lever-type locking elements, clamp-type locking elements, camtype locking elements, spring-type locking elements, pin-type locking elements.

[0114] The number of locking elements 415 is not limitative for the present disclosure, and may be chosen according to specific design parameters (for example, according to the type of locking). In the exemplary (and non-limiting) considered embodiment, the locking elements 415 comprise two locking nuts associated with each sliding element 410, arranged opposite sides thereof along the longitudinal direction X.

[0115] In the exemplary considered embodiment, the connection mechanism comprises two or more housing elements 420A each one associated with a respective sliding element 410, and two or more connection elements 420c each one connectable to a respective fixing component and to a respective sliding element 410 (for example, as discussed below, through insertion of the connection element 420c in the housing element 420A associated with the sliding element 410).

[0116] The number of housing elements 420A and of connection elements 420c is not limitative for the present disclosure, and may be chosen according to specific design parameters.

[0117] As visible in Figs.4A and 4B, each housing element 420A, preferably having a hollow cylindrical shape, extends along the vertical direction Z from the respective sliding element 410, substantially orthogonally with respect to it (and with respect to the threaded rod 405), and is advantageously arranged laterally to it along the transversal direction Y (so as not to compromise the maneuverability of the sliding element 410). Each housing element 420A is integral with the respective sliding element 410 (each housing element 420A being formed in a single piece construction with the respective sliding element 410 or coupled to it in a substantially irreversible manner, for example through welding, riveting, bonding, press-fit) such that, when the connection elements 420c are connected to the fixation components and to the sliding elements 410, the movement of the sliding elements 410 causes the movement of the fixation components, and hence of the bone portions into which they are inserted.

[0118] Each connection element 420c, preferably having a solid cylindrical shape, is adapted to be inserted into the housing element 420A and be coupled to it, preferably in reversible manner (for example, through screws and / or bolts, clamps and / or fasteners, snap-fit or press-fit joints, quick connectors). Without loss of generality, each connection element 420c is shaped and / or sized according to shape and / or size of the respective housing element 420A and / or according to coupling modes for coupling the connection element 420c and the housing element 420A.

[0119] Each connection element 420c preferably comprises one or more holes 420CH (for example, through holes or blind holes), extending, in use, along the transversal direction Y, and adapted to receive one or more respective fixation components. In this way, the insertion of a fixing component in the hole 420CH causes the coupling of the fixing component to the corresponding connection element 420c (coupling that may be obtained through thread of the hole 420CH, and / or through locking nuts, washers and / or adhesives applied to the hole 420CH and / or to the fixing component), and hence to the sliding element 410 to which the latter is coupled.

[0120] According to an embodiment, the reduction device 115, with the exception of the connection elements 420c, is made of steel.

[0121] According to an embodiment, the connection elements 420c are preferably made of a radiolucent material, for example carbon o carbon composite: this allows, during real-time radiographic imaging procedures (such as fluoroscopy), high-quality images with a substantial reduction of interference and artifacts: the surgeon therefore has a clear view of the anatomical structures, resulting in benefits in terms of the safety and effectiveness of the reduction procedure and of the following procedure of application of the fixation device 105.

[0122] The reduction device 115, due to its peculiar features exposed above, may form a separate and independent aspect of the present disclosure.

[0123] The described PCS system 100 is configured for the treatment of calcaneal fractures of a single foot, particularly the right foot. In this respect, the present disclosure is intended to be applicable to a PCS system, substantially mirror- symmetrical to the PCS system 100, for the treatment of calcaneal fractures of the contralateral foot. Such a mirror PCS system, not shown, is conceptually analogous to the PCS system 100, from which it essentially differs only in geometric adaptations, for example — but not limited to — the mirror orientation and / or angles of the secondary fixing screws 210i-210e, the mirror orientation and / or angles of the insertion holes 2151-2156, the mirror orientation and / or angles of the central arm 305 and / or of one or more of the lateral arms 310T,310L, and the mirror orientation and / or angles of the guiding holes 315i-315e.

[0124] Naturally, in order to meet contingent and specific requirements, a person skilled in the art may make numerous logical and / or physical modifications and variations to the present disclosure. More specifically, although such disclosure has been described with a certain level of detail with reference to one or more embodiments, it is understood that various omissions, substitutions, and changes in form and detail, as well as other embodiments, are possible. In particular, different embodiments of the present disclosure can be implemented even without the specific details (such as numerical values) provided in the previous description to allow a more complete understanding; conversely, well-known features may have been omitted or simplified so as not to obscure the description with unnecessary particulars. Moreover, it is expressly intended that specific elements and / or method steps described in relation to any embodiment of the present disclosure may be incorporated into any other embodiment as a normal design choice.

Claims

CLAIMS1. System (100) for treating calcaneal fractures comprising: a fixation device (105), of the internal type, for calcaneal fracture osteosynthesis, the fixation device comprising a main fixing screw (205) and a plurality of secondary fixing screws (210i-210e), wherein the main fixing screw is adapted to be inserted in the heel along a longitudinal direction (X) identifying a prevalent extension direction of the foot, the main fixing screw (205) comprising a plurality of insertion holes (215i-215e) adapted to allow the secondary fixing screws (210i-210e) to be inserted through the main fixing screw (205), transversally to the main fixing screw, at respective insertion angles, and an application device (110) adapted to guide the application of the plurality of secondary fixing screws (210i-210e) into the main fixing screw (205) of the fixation device (105), the application device comprising:- a first arm (305) adapted to the coupling of the application device (110) to the main fixing screw;- a plurality of second arms (310T,310L) comprising a plurality of guiding holes (315i-315e) adapted to guide the application of the secondary fixing screws to the main fixing screw, when the application device (110) is coupled to the main fixing screw (205) the guiding holes being aligned to the insertion holes (215i-215e), and- a clamping member (SX) adapted to clamp the first arm to the main fixing screw to secure and keep securely fastened the application device to the main fixing screw during application of the secondary fixing screws (210i-210e) to the main fixing screw (205).

2. System (100) according to claim 1, wherein, on a lateral plane identified by the longitudinal direction (X) and by a vertical direction (Z) orthogonal to the longitudinal direction (X), with respect to the vertical direction (Z):- the insertion angle of a first (215i) and of a second (215z) insertion holes of said plurality of insertion holes (215i-215e) is equal to 10°;- the insertion angle of a third insertion hole (215s) of said plurality of insertion holes (215i-215e) is equal to 0°;- the insertion angle of a fourth insertion hole (215i) of said plurality ofinsertion holes (215i-215e) is equal to 15-20°;- the insertion angle of a fifth insertion hole (215s) of said plurality of insertion holes (215i-215e) is equal to 25-30°.

3. System (100) according to claim 2, wherein, on a front plane identified by the vertical direction (Z) and by a transverse direction (Y) orthogonal to the longitudinal direction (X) and to the vertical direction (Z), with respect to the vertical direction (Z):- the insertion angle of the first (215i), second (215z), and third (215i) insertion holes is equal to 0°;- the insertion angle of the fourth insertion hole (2154) is equal to 25-30°;- the insertion angle of the fifth insertion hole (215s) is equal to 30-35°;- the insertion angle of a sixth insertion hole (215e) of said plurality of insertion holes (215i-215e) is equal to 90°.

4. System (100) according to claim 2 or 3, wherein, on a top plane identified by the longitudinal direction (X) and by the transverse direction (Y), with respect to the transverse direction (Y):- the insertion angle of the fourth insertion hole (2154) is equal to 25°;- the insertion angle of the fifth insertion hole (215s) is equal to 30°;- the insertion angle of the sixth insertion hole (215e) is equal to 10°.

5. System (100) according to any of the preceding claims, wherein the main fixing screw (205) comprises coupling portions (205SA,205SS) configured to allow the coupling, to the main fixing screw, of the application device (110).

6. System (100) according to any of the preceding claims, wherein the first arm (305) comprises:- at a first end thereof that, in use, faces the main fixing screw (205), one or more engagement elements (305A) for centering and engaging the application device (110) to the main fixing screw (205); and- a cavity (305c) extending from the first end of the first arm (305) to a secondend of the first arm (305) opposite to the first end, said cavity being adapted to receive the clamping member (SX).

7. System (100) according to any of the preceding claims, wherein said plurality of second arms (310T,310L) is made of a radiolucent material, for example carbon or carbon composite.

8. System (100) according to any of the preceding claims, further comprising a reduction device (115) adapted to allow the reduction of the calcaneal fracture.

9. System (100) according to claim 8, wherein the reduction device comprises:- a main structure (405);- fixation components adapted to be inserted in the heel;- an adjusting mechanism (410,415) connected to the main structure; and- a connection mechanism (420A, 420c) adapted to connect the adjusting mechanism to the fixation components, said connection mechanism (420A, 420c) comprising one or more connection elements (420c) made of a radiolucent material, for example carbon o carbon composite.

10. Application device (110) adapted to the use in the system (100) according to any of the preceding claims, the application device comprising:- a first arm (305) adapted to the coupling of the application device (110) to the main fixing screw;- a plurality of second arms (310T,310L) comprising a plurality of guiding holes (315i-315e) adapted to guide the application of the secondary fixing screws to the main fixing screw, when the application device (110) is coupled to the main fixing screw (205) the guiding holes being aligned to the insertion holes (215i-215e), and- a clamping member (SX) adapted to clamp the first arm to the main fixing screw to secure and keep securely fastened the application device to the main fixing screw during the application of the secondary fixing screws (210i-210e) to the main fixing screw (205).

11. Method for treating calcaneal fractures, the method comprising: forming a calcaneal channel; inserting and screwing the main fixing screw (205) of the fixation device (105) of the system (100) according to any claim 1-9 into the calcaneal channel; coupling the application device (110) of the system (100) according to any claim 1-9 to the main fixing screw, through the first arm (305) and the clamping member (SX); inserting the secondary fixing screws (210i-210e) into the insertion holes (215i-215e) of the main fixing screw through the plurality of guiding holes (315i-315e) of the plurality of second arms (310T,310L) of the application device; decoupling the application device from the main fixing screw.

Images