A pedicle screw suitable for spinal percutaneous internal fixation

Abstract

In order to solve the problem that the existing pedicle screws are not suitable for minimally invasive surgery, the present invention provides a pedicle screw suitable for spinal percutaneous internal fixation, comprising a rod portion, and also comprising a head connected to the rod portion; a fixing rod fastening structure is arranged on the head portion; the head portion comprises a fixing rod clamping mechanism; the fixing rod clamping mechanism comprises a first clamping arm and a second clamping arm; the first clamping arm and / or the second clamping arm are movably connected to the head portion; and also comprises a clamping arm fastening structure for fastening the first clamping arm to the second clamping arm. The pedicle screw of the present invention is easy to operate and has a high success rate.

Description

Technical Field

[0001] The invention relates to a screw for spinal column fixation, in particular to a screw suitable for spinal column percutaneous pedicle fixation. Background Art

[0002] Spinal fixation is the most commonly used technique in spinal surgery. In order to reduce the trauma of surgery to the human body, this technique has also tended to be minimally invasive. Percutaneous spinal screw fixation is a minimally invasive technique that has been developed in recent years and is still under research. The so-called percutaneous spinal screw placement refers to the use of precise positioning techniques such as fluoroscopy, navigation or robots to place each pedicle screw into the pedicle of the spine through a small skin incision. Compared with the classic open incision screw placement, percutaneous spinal screw fixation abandons the long incision of open surgery and replaces it with multiple small incisions for screw insertion, which preserves the integrity of the tissue between the screws, reduces the scope of surgical anatomical exposure, and thus reduces surgical trauma.

[0003] At present, the same pedicle screws are used in both percutaneous spinal screw placement and open incision screw placement. This pedicle screw has a U-shaped groove head, and the opening of the U-shaped groove faces upward. The fixing rod passes through the U-shaped grooves of several pedicle screws horizontally, and then the fixing screw core is screwed into the opening of each U-shaped groove to compress the fixing rod. In the open incision screw placement, since the pedicle screws are in the open screw placement state of the long incision, the U-shaped groove heads of all pedicle screws are exposed in the surgical field of view, and the operator can guide the fixing rod from the upper opening of the U-shaped groove into the U-shaped groove under direct vision, and finally lock the fixing rod with the tightening screw core. However, during the percutaneous screw placement and internal fixation of the spine, due to the use of a small incision, the fixation rod cannot be directly inserted from the top of the opening of the U-shaped groove. The fixation rod can only be inserted from the side of the U-shaped groove of one pedicle screw, and then sneak through the paravertebral muscles and tissues to the side of the U-shaped groove of another screw. After confirming the position of the U-shaped groove, the fixation rod is passed through the U-shaped groove. The width of the U-shaped groove is only about 5 mm, while the diameter of the commonly used fixation rod in clinical practice is 5 mm. Therefore, there are extremely high requirements for the operation accuracy of inserting the U-shaped groove. In the process of passing the fixation rod through the muscles and tissues, the fixation rod is blocked and pulled by various tissues such as skin, fascia, muscle, tendon, etc. At the same time, due to the different anatomical positions of the fixed vertebrae and the influence of disease changes, the arrangement direction and angle of the inserted pedicle screws will be different. Therefore, the sides of the U-shaped grooves of different pedicle screws are not parallel. Therefore, the fixation rod also needs to be pre-bent to a certain curvature and cannot be in a straight rod state. These factors make it very difficult to insert the fixation rod secretly, which requires repeated attempts and checks, and even multiple fluoroscopy and adjustment of the pedicle screw position and the pre-bend of the fixation rod. This increases the collateral damage to the patient and greatly reduces the significance of "percutaneous screw internal fixation", a minimally invasive surgery that aims to reduce surgical trauma to the patient. Summary of the invention

[0004] In order to solve the problem that the existing pedicle screws are not suitable for minimally invasive surgery, the present invention provides a pedicle screw suitable for percutaneous spinal fixation.

[0005] The technical solution of the present invention is as follows:

[0006] A pedicle screw suitable for percutaneous internal fixation of the spine comprises a rod portion and a head portion connected to the rod portion; a fixing rod fastening structure is arranged on the head portion; the head portion comprises a fixing rod clamping mechanism; the fixing rod clamping mechanism comprises a first clamping arm and a second clamping arm; the first clamping arm and / or the second clamping arm are movably connected to the head portion; and also comprises a clamping arm fastening structure for fastening the first clamping arm to the second clamping arm.

[0007] Optionally, the fixed rod clamping mechanism includes an annular body; the annular body includes the first clamping arm and the second clamping arm; the first clamping arm and the second clamping arm are connected to form the annular body; the fixed rod fastening structure includes a fixed rod fastening hole; the annular body is provided with the fixed rod fastening hole that passes through the annular body, and the extension line of the axis of the fixed rod fastening hole extends into the ring formed by the annular body.

[0008] Optionally, the fixing rod fastening hole is arranged on the first clamping arm and / or the second clamping arm.

[0009] Optionally, the fixing rod fastening hole is formed by joining the first clamping arm and the second clamping arm.

[0010] Optionally, a force point for the opening and closing tool to apply force is provided on the annular body.

[0011] Optionally, the force point is arranged on the first clamping arm and / or the second clamping arm.

[0012] Optionally, the force point includes a groove or a pin arranged on the annular body.

[0013] Optionally, the clamping arm fastening structure includes a fastening connector; the fastening connector is respectively provided with a first fixing mechanism and a second fixing mechanism; the first fixing mechanism is connected to the first clamping arm; and the second fixing mechanism is connected to the second clamping arm.

[0014] Optionally, the first fixing mechanism includes a first fixing hole or a first fixing hook.

[0015] Optionally, the second fixing mechanism includes a second fixing hook or a second fixing hole.

[0016] Optionally, a first step structure is provided at the butt end of the first clamping arm; and a second step structure matching the first step structure is provided at the butt end of the second clamping arm.

[0017] Optionally, the portion of the head connected to the rod portion is a rod connecting section; when the fixing rod is clamped by the fixing rod clamping mechanism, the surface on which the rod connecting section contacts the fixing rod is an inner surface of the rod connecting section; and the inner surface of the rod connecting section matches the outer surface of the fixing rod.

[0018] Optionally, the first clamping arm and / or the second clamping arm is hinged to the rod connecting section; the first clamping arm and / or the second clamping arm hinged to the rod connecting section includes an integral clamping arm, and the integral clamping arm is hinged to the rod connecting section via a pivot; the integral clamping arm is divided into two parts with the pivot as the dividing point: a first part and a second part; the integral clamping arm can rotate around the axis of the pivot so that the second part protrudes from the inner surface of the rod connecting section.

[0019] Optionally, a second portion surface is provided on the second portion; when the fixing rod is clamped by the fixing rod clamping mechanism, the second portion surface matches with an outer surface of the fixing rod.

[0020] Optionally, the clamping arm fastening structure includes: in the assembled state, a first external thread is provided on the surface of the first clamping arm facing away from the second clamping arm; in the assembled state, a second external thread is provided on the surface of the second clamping arm facing away from the first clamping arm; the clamping arm fastening structure includes the first external thread and the second external thread.

[0021] Optionally, the first clamping arm and the second clamping arm constitute a U-shaped fixed rod clamping mechanism; in the assembled state, a first internal thread is provided on the surface of the first clamping arm facing the second clamping arm; in the assembled state, a second internal thread is provided on the surface of the second clamping arm facing the first clamping arm; the fixed rod fastening structure includes the first internal thread and the second internal thread.

[0022] Optionally, the fixing rod fastening structure includes a fixing rod fastening screw; the external thread of the fixing rod fastening screw matches the first internal thread and the second internal thread; the clamping arm fastening structure includes a clamping arm fixing nut; the internal thread of the clamping arm fixing nut matches the first external thread and the second external thread.

[0023] The technical effects of the present invention are as follows:

[0024] The pedicle screw of the present invention, which is suitable for spinal percutaneous internal fixation, is provided with a fixing rod clamping mechanism at the head. When the first clamping arm and / or the second clamping arm of the fixing rod clamping mechanism can be rotated to a position so that the fixing rod clamping mechanism is in a clamping state (a state in which the distance between the first clamping arm and the second clamping arm is the smallest), the fixing rod fastening structure can stably clamp the fixing rod under the fastening connection of the clamping arm fastening structure, thereby realizing the function of the pedicle screw. The fixing rod clamping mechanism can also use tools such as open-end pliers to push the movable clamping arm, so that the fixing rod clamping mechanism is in an open state (the first clamping arm and the second clamping arm are in a state of being away from each other), providing a larger passing space for the fixing rod to pass through the side of the fixing rod clamping mechanism.

[0025] The idea of ​​the present invention is to provide a larger passing space for the fixing rod to pass through by setting a fixing rod clamping mechanism that can be opened and closed, thereby reducing the precision requirements for the fixing rod passing operation. At the same time, the fixing rod with a certain curvature does not need to be repeatedly adjusted and can directly pass through the opened fixing rod clamping mechanism. Therefore, the pedicle screw of the present invention reduces the difficulty of operation, reduces collateral damage, improves the success rate of operation, and achieves the purpose of the present invention.

[0026] The further effects of the above optional manner will be described below in conjunction with the specific implementation manner. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 It is a front view of a first embodiment of a pedicle screw of the present invention.

[0028] Figure 2 for Figure 1 Top view of the illustrated embodiment.

[0029] Figure 3 for Figure 1 A perspective view of the illustrated embodiment.

[0030] Figure 4 for Figure 1 A perspective view of the ring body of the illustrated embodiment in an open state.

[0031] Figure 5 It is a front view of a second embodiment of a pedicle screw of the present invention.

[0032] Figure 6 for Figure 5 Top view of the illustrated embodiment.

[0033] Figure 7 for Figure 5 A perspective view of the illustrated embodiment.

[0034] Figure 8 for Figure 5 Exploded view of the illustrated embodiment.

[0035] Fig. 9 for Figure 5 A diagram of the clamping arms of the illustrated embodiment in an open state.

[0036] Fig.10 for Figure 5 An enlarged perspective view of the clamp arm fastening structure in the illustrated embodiment.

[0037] Fig.11 It is a stereoscopic view of a third embodiment of a pedicle screw of the present invention.

[0038] Fig.12 for Fig.11 Exploded view of the illustrated embodiment.

[0039] Fig.13 for Fig.11 Assembly drawing of the illustrated embodiment.

[0040] The symbols in the figure are explained as follows:

[0041] 101, first clamping arm; 1011, first part; 1012, second part; 102, fastening screw core; 103, second clamping arm; 104, rod connecting section; 105, rod part; 106, inner surface of the rod connecting section;

[0042] 201. Focus point; 202. Focus point;

[0043] 301. second surface; 302. pivot;

[0044] 401, screw hole; 402, screw hole; 403, first step structure; 404, second step structure;

[0045] 501, first clamping arm; 5011, first part; 5012, second part; 502, fixing rod fastening screw; 503, clamping arm fastening structure; 504, second clamping arm; 505, pivot; 506, rod connecting section; 507, rod part; 508, inner surface of rod connecting section; 509, pivot;

[0046] 601. Focus point; 602. Focus point;

[0047] 801, fixing rod fastening screw hole;

[0048] 901, second step structure; 902, first step structure; 903, second surface;

[0049] 1001, fixing hole; 1002, fixing hook;

[0050] 1101, first clamping arm; 1102, first external thread; 1103, first internal thread; 1104, second internal thread; 1105, second external thread; 1106, second clamping arm; 11061, first portion; 11062, second portion; 1107, pivot; 1108, second portion surface; 1109, rod;

[0051] 1201, clamping arm fixing nut; 1202, fixing rod fastening screw. DETAILED DESCRIPTION

[0052] The technical solution of the present invention is described in detail below in conjunction with the embodiments shown in the accompanying drawings.

[0053] It should be pointed out that the accompanying drawings are schematic diagrams. In order to highlight the main structure of the present invention, the accompanying drawings are not strictly based on the drawing scale of the actual product, but this does not affect the understanding of the technical solution of the present invention by those skilled in the art.

[0054] Figures 1 to 4 The specific structure of the first embodiment of the pedicle screw of the present invention is shown. Figures 1 to 4 It can be seen that the pedicle screw of the present invention includes a rod 105 and a head connected to the rod 105 above the rod 105. The rod 105 includes a screw that can be inserted into the pedicle (that is, the rod 105 is provided with an external thread, Figure 1 The head portion includes a ring-shaped body exposed outside the pedicle. A hollow tube (not shown in the figure) is provided in the rod portion 105. Figure 1In the embodiment shown, the annular body is a circular annular body composed of three arc segments, namely, the integrated first clamping arm 101, the integrated second clamping arm 103 and the rod connecting section 104. The rod connecting section 104 is connected to the rod portion 105, and the two ends of the rod connecting section 104 are respectively hinged to the first clamping arm 101 and the second clamping arm 103. The other end of the first clamping arm 101 and the other end of the second clamping arm 103 are butted, so that the three arc segments of the first clamping arm 101, the second clamping arm 103 and the rod connecting section 104 form the annular body (i.e., the fixing rod clamping mechanism) that can clamp the fixing rod. The shape of the inner annular surface of the annular body matches the outer surface of the cylindrical fixing rod that can be assembled. That is, the inner surface 106 of the rod connecting section belonging to the inner annular surface matches the outer surface of the assembled fixing rod, and the two form surface contact in the assembled state. The integrated first clamping arm 101 and second clamping arm 103 mentioned here refer to that the clamping arm itself is a single integral part, and the integral part does not include two or more parts that can move or rotate relative to each other. In other embodiments, the annular body can be non-circular, for example, the inner contour of the annular body is rectangular, etc., as long as a closed annular body is formed. In other embodiments, a solution of combining a clamping arm and a rod connecting section into an annular body can also be adopted, and a solution of more clamping arms connected together can also be adopted.

[0055] A fixing rod fastening hole is provided on the annular body. Figure 1 In the illustrated embodiment, the fixing rod fastening hole is a fastening screw hole, and the fastening screw hole is for the fastening screw core 102 to be screwed into and fastened to the fixing rod assembled in the annular body. The fastening screw hole penetrates the annular body, so that the fastening screw core 102 can be screwed into the fastening screw hole from the outside of the annular body, and extend into the inside of the ring of the annular body. That is, the extension line of the axis of the fastening screw hole extends into the ring formed by the annular body, and the axis of the fastening screw hole is on the same straight line as the axis of the rod 105. In other embodiments, the fixing rod fastening hole can adopt other forms of holes for fasteners to pass through and fasten the fixing rod, which will not be repeated here.

[0056] exist Figures 1 to 4 As can be seen in the figure, the first clamping arm 101 and the second clamping arm 103 can rotate with the hinge axis (i.e., the pivot 302) with the rod connecting section 104 as the rotation center, so that the first clamping arm 101 and the second clamping arm 103 can be separated or connected at the docking point, so that the annular body can be Figure 1 The closed state shown and Figure 4 The expanded states shown in the figure are switched between. Figure 3 and Figure 4As shown, the surface of the rod connecting segment 104 facing the inside of the annular body is the rod connecting segment inner surface 106. The rod connecting segment inner surface 106 matches the outer surface of the fixing rod, that is, when the fixing rod is assembled to the annular body, the rod connecting segment inner surface 106 forms a surface contact with the outer surface of the fixing rod. Figure 3 and Figure 4 It can also be seen that the first clamping arm 101 is divided into a first part 1011 and a second part 1012 with the pivot 302 as the boundary. The second part 1012 is a convex step structure, and the part of the rod connecting section 104 adjacent to it is provided with a corresponding concave step structure. The second part 1012 is also provided with a second surface 301 that matches the outer surface of the fixing rod. That is, when the annular body is formed, it is in a state as shown in FIG. Figure 1 and Figure 3 When the fixing rod is assembled into the annular body, the second surface 301 forms a surface contact with the outer surface of the fixing rod. Figure 4 In the unfolded state shown, that is, when the first clamping arm 101 and the second clamping arm 103 are in a separated state, the first clamping arm 101 rotates around the pivot 302 to form a lever movement, and the second portion 1012 tilts up and protrudes from the inner surface 106 of the rod connecting section.

[0057] The first clamping arm 101 and the second clamping arm 103 are respectively provided with a matching and staggered first step structure 403 and a second step structure 404 at their butt ends (i.e., the ends where the two are butted against each other). The first step structure 403 and the second step structure 404 increase the contact area at the butt joint of the first clamping arm 101 and the second clamping arm 103, which is conducive to improving the stability of the butt joint between the two. In addition, a screw hole 401 is provided on the first step structure 403, and a screw hole 402 is provided on the second step structure 404. After the first clamping arm 101 and the second clamping arm 103 are butt jointed, the screw hole 401 and the screw hole 402 overlap to form a single screw hole (i.e., the aforementioned fastening screw hole). The fastening screw hole can be screwed into by the fastening screw core 102. At the same time, the fastening screw core 102 can also further firmly connect the first clamping arm 101 and the second clamping arm 103. It can be seen that the fastening screw core and the fastening screw hole also constitute a clamping arm fastening structure that fastens the first clamping arm 101 and the second clamping arm 103 .

[0058] from Figure 2 , Figure 3 and Figure 4As can be seen, outside the annular body, adjacent to the fastening screw core 102, a force point 201 is provided on the first clamping arm 101, and a force point 202 is provided on the second clamping arm 103. The force point 201 and the force point 202 are symmetrically arranged with the axis of the fastening screw core 102 as the center. In the present embodiment, the force point 201 is a wedge-shaped groove, and the depth of the bottom of the wedge-shaped groove from the outer surface of the annular body increases as the distance of the bottom position from the fastening screw hole (i.e., the location of the fastening screw core 102) increases. The force point is a force point for facilitating the operation of the instrument to apply a force to separate the first clamping arm 101 and the second clamping arm 103. In other embodiments, the force point can be implemented by a common equal-depth groove or pin column (such as a protruding cylinder) and other structures.

[0059] The following Figures 1 to 4 The working process of the embodiment shown is described to further illustrate the technical solution of the present invention.

[0060] Under fluoroscopy, the projected position of the target pedicle on the body surface is determined, a small incision is made, and the entrance of the pedicle bone canal is opened on the vertebral body through the skin, fascia and muscle. The pedicle bone canal is probed through the open vertebra and the metal guide wire is inserted. After the accurate position of the guide wire is confirmed by fluoroscopy, the tail end of the external part of the metal guide wire is passed through the hollow tube in the rod 105 and led out from the tail end of the rod 105. Figure 1 The pedicle screw is introduced into the body along the metal guide wire to the opening of the pedicle bone channel, the pedicle screw is screwed into the bone channel, and then the metal guide wire is withdrawn, and the position of the pedicle screw is confirmed by perspective. That is, the pedicle screw is placed in the target pedicle. At this time, under the pressure of the surrounding tissue, the first clamping arm 101 and the second clamping arm 103 remain in a docking and closed state.

[0061] Place the two tips of the open-end pliers into the force point 201 and the force point 202 respectively, and along the bottom of the wedge-shaped groove at the force point, press the two tips of the open-end pliers against the side walls of the wedge-shaped groove respectively, and then operate the hand-held part of the open-end pliers so that the two tips of the open-end pliers press against the side walls of the wedge-shaped groove, and at the same time perform the action of separating the first clamping arm 101 and the second clamping arm 103, so that the first clamping arm 101 is separated from the second clamping arm 103, so that the annular body is in an expanded state. Then, the fixing rod is inserted into the annular body along the lateral direction of the annular body (that is, the direction in which the fixing rod extends into the annular body is substantially perpendicular to the annular body). Figure 1The annular plane of the annular body shown in the figure extends into the annular body in the expanded state. Since the annular body is in the expanded state at this time, the insertion of the fixing rod has a larger tolerance space, which reduces the operation accuracy requirements, avoids repeated adjustments to the fixing rod with a smaller curvature, and improves the success rate of the operation. If the curvature of the fixing rod is large, the larger adjustment space of the opened annular body is also conducive to adjusting the curvature of the fixing rod. At the same time, operations such as pressurization, expansion, rotation and derotation between pedicle screws are also convenient to perform. The shape of the inner ring of the annular body can be set to match the shape of the cross section of the fixing rod. For example, the circular inner ring of the annular body in this embodiment can form a surface contact with the fixing rod with a circular cross section, thereby enhancing the stability of the connection between the fixing rod and the annular body.

[0062] After the fixing rod passes through the annular body, the opening jaws are withdrawn while pressing down the fixing rod. Figure 4 The annular body is in the unfolded state shown in the figure. When the fixing rod is pressed down, the tilted second part 1012 (and the second part of the symmetrically arranged second clamping arm 103) is pressed. Based on the principle of lever, the first part 1011 (and the first part of the symmetrically arranged second clamping arm 103) rotates with the pivot 302 as the rotation center, so that the first clamping arm 101 and the second clamping arm 103 are closed. After the first clamping arm 101 and the second clamping arm 103 are closed, the following is formed. Figure 1 After the annular body is closed, the second portion surface 301 is flush with the adjacent rod connecting segment inner surface 106, that is, there is no height difference between the second portion surface 301 and the adjacent rod connecting segment inner surface 303, and it matches the outer surface of the fixing rod. Therefore, the pressing fixing rod causes the second portion 1012 to continue to rotate until the first clamping arm 101 and the second clamping arm 103 are butted to achieve the following Figure 1 and Figure 3 The final closed state of the annular body shown, i.e., the arrangement of the first portion 1011 and the second portion 1012, enables the first clamping arm 101 and the second clamping arm 103 to be closed by only pressing down the fixing rod, without requiring additional operations, thus reducing the difficulty of operation.

[0063] After the first clamping arm 101 and the second clamping arm 103 are butted together, the screw hole 401 overlaps with the screw hole 402 to form a single screw hole. The single screw hole is a fastening screw hole, into which the fastening screw core 102 can be screwed. The fastening screw core 102 can fasten the fixing rod and can also fasten the first clamping arm 101 and the second clamping arm 103. Of course, if the butt joint of the first clamping arm 101 and the second clamping arm 103 cannot make the screw hole 401 and the screw hole 402 completely overlap to form a fastening screw hole due to reasons such as manufacturing accuracy, fine adjustment can be performed through the force points 201 and 202 by tools such as pliers to finally form a fastening screw hole.

[0064] Figures 5 to 10 A specific structure of a second embodiment of the present invention is shown. Figure 5 The pedicle screw shown includes a rod 507 and a head connected to the rod 507. The rod 507 includes a screw rod ( Figure 5 The head portion includes a ring-shaped body exposed outside the pedicle. A hollow tube (not shown in the figure) is provided in the rod portion 507. Figure 5 In the embodiment shown, the annular body is a circular annular body composed of three arc segments, namely, the first clamping arm 501, the second clamping arm 504 and the rod connecting segment 506. The rod connecting segment 506 is connected to the rod portion 507, and the two ends of the rod connecting segment 506 are respectively hinged to the first clamping arm 501 and the second clamping arm 504. The other end of the first clamping arm 501 and the other end of the second clamping arm 504 are butted, so that the three arc segments, namely, the first clamping arm 501, the second clamping arm 504 and the rod connecting segment 506, form the annular body.

[0065] from Figures 5 to 10 It can be seen that the second embodiment is Figures 1 to 4 The basic structures of the embodiments shown are the same, and the functions realized by the parts with the same names are also the same. For specific functional and structural details, reference can be made to the description of the parts with the same names in the first embodiment. For example, the first part 5011, the second part 5012, the force point 601, the force point 602, the second part surface 903, the pivot 509, the inner surface 508 of the rod connecting section, etc. Similar to the first embodiment described above, the first clamping arm 501 has the first part 5011 and the second part 5012, and the second part surface 903 matching the outer surface of the fixed rod, so that the first clamping arm 501 (the second clamping arm 504 also has the same structure and function) can be closed only by pressing the fixed rod downward, which is easy to operate.

[0066] Figures 5 to 10 The embodiment shown is different from the first embodiment in that: the fixing rod fastening screw hole 801 is set on the second clamping arm 504, and is not formed by docking and splicing the first clamping arm 501 and the second clamping arm 504; the implementation method of the clamping arm fastening structure 503 is different; the force point 601 and the force point 602 are grooves with equal depth and rectangular cross-sections; the connection method of the first step structure 902 and the second step structure 901 is different from the same structure in the first embodiment, but both can increase the contact area between the two docking to improve the stability of the connection between the two. The part of this embodiment involving the clamping arm fastening structure 503 is described in detail below.

[0067] Since the fixing rod fastening screw hole 801 of the present embodiment is only arranged on the second clamping arm 504, the fixing rod fastening screw 502 cannot fasten the first clamping arm and the second clamping arm at the same time as the fastening screw core 102 in the first embodiment. However, it is difficult for the first clamping arm 501 and the second clamping arm 504 to maintain a stable connection that meets the requirements only by the friction between the first step structure 902 and the second step structure 901. When the fixing rod is assembled between the first clamping arm 501 and the second clamping arm 504, due to the force of the spine, the fixing rod decomposes the corresponding force to the first clamping arm 501 or the second clamping arm 504, so that the first clamping arm 501 and the second clamping arm 504 have a tendency to separate, and the fixing rod has a tendency to detach from the pedicle screw. For this reason, it is necessary to strengthen the connection between the first clamping arm 501 and the second clamping arm 504. In this embodiment, a clamping arm fastening structure 503 is used to strengthen the connection between the first clamping arm 501 and the second clamping arm 504. Fig.10 It can be seen that the clamping arm fastening structure 503 is a long strip-shaped part, which has an arc-shaped middle portion that matches the arc of the outer surface of the annular body. One end of the clamping arm fastening structure 503 is a closed fixing hole 1001, and the other end is a fixing hook 1002 with a hook-shaped structure. Figures 5 to 8 It can be seen that the fixing hole 1001 is sleeved on the fixing rod fastening screw 502, and the fixing hook 1002 is hooked on the side wall of the groove of the force point 602. It can be seen that the two ends of the clamping arm fastening structure 503 are respectively connected to the fixing rod fastening screw 502 on the first clamping arm 501 (equivalent to connecting the first clamping arm 501) and the second clamping arm 504, thereby firmly connecting the two. In other embodiments, the fixing hole 1001 can also be replaced by a non-closed hook-shaped structure (such as a semicircular arc structure, which is also a fixing hook); if the force point 602 is replaced by a pin, the fixing hook can be set as a fixing hole. In other embodiments, the two ends of the clamping arm fastening structure may be provided with fixing hooks or fixing holes, respectively, and connected to the fulcrum points on the first clamping arm and the fulcrum points on the second clamping arm, respectively; if in such embodiments, the clamping arm fastening structure needs to pass through the fixing rod fastening screw (the fixing rod fastening screw is not required as the connecting fixing structure of the clamping arm fastening structure), then a hole for sleeve-connecting the fixing rod fastening screw or a bending structure for bypassing the fixing rod fastening screw is provided at the corresponding part of the clamping arm fastening structure. Other similar examples of the connection of the clamping arm fastening structure are not listed one by one here.

[0068] Figures 11 to 13The specific structure of the third embodiment of the present invention is shown. As in the previous two embodiments, the pedicle screw of this embodiment also has a rod 1109, a first part 11061, a second part 11062, a pivot 1107, a second part surface 1108, etc. with the same functions as the components of the same name. The specific functional and structural details of these parts can refer to the description of the components of the same name in the first and second embodiments. The differences between this embodiment and the previous two embodiments are described in detail below.

[0069] In this embodiment, at the head, the first clamping arm 1101 and the second clamping arm 1106 form a U-shaped fixed rod clamping mechanism, that is, the first clamping arm 1101 and the second clamping arm 1106 are not butted together, and there is a space between them in the assembled state. The first clamping arm 1101 is connected to the rod 1109 as a whole, and the second clamping arm 1106 is hinged to the first clamping arm 1101 through the pivot 1107. Similar to the above two embodiments, the second clamping arm 1106 has a first part 11061 and a second part 11062, and a second part surface 1108 matching the outer surface of the fixed rod, so that the second clamping arm 1106 can be closed by only pressing the fixed rod downward, which is easy to operate.

[0070] In such Fig.12 and Fig.13 In the assembled state of the present embodiment shown, a first internal thread 1103 is provided on the concave surface of the first clamping arm 1101 facing the second clamping arm 1106, a first external thread 1102 is provided on the convex surface of the first clamping arm 1101 facing away from the second clamping arm 1106, a second internal thread 1104 is provided on the concave surface of the second clamping arm 1106 facing the first clamping arm 1101, and a second external thread 1105 is provided on the convex surface of the second clamping arm 1106 facing away from the first clamping arm 1101.

[0071] like Fig.12 and Fig.13 As shown, the clamping arm fixing nut 1201 has an internal thread, which matches the first external thread 1102 and the second external thread 1105, so that the clamping arm fixing nut 1201 can be screwed onto the first clamping arm 1101 and the second clamping arm 1106 through threaded connection, and can firmly connect the first clamping arm 1101 and the second clamping arm 1106 as a clamping arm fastening structure. Figures 1 to 10 In the embodiment of the present invention in which the head shown has an annular body, external threads can be set on the outside of the first clamping arm and the outside of the second clamping arm, and clamping arm fixing nuts (refer to clamping arm fixing nut 1201) matching the external threads can be used to constitute the clamping arm fastening structure in this embodiment.

[0072] like Fig.12 and Fig.13 As shown, the fixing rod fastening screw 1202 has an external thread, which matches the first internal thread 1103 and the second internal thread 1104. When the first clamping arm 1101 and the second clamping arm 1106 are fixedly connected by the clamping arm fixing nut 1201, the fixing rod fastening screw 1202 can be screwed into the screw hole formed by the space between the first internal thread 1103 and the second internal thread 1104, thereby fastening the fixing rod between the first clamping arm 1101 and the second clamping arm 1106, thereby playing the function of a fixing rod fastening structure.

[0073] The pedicle screw of the present invention is applicable not only to spinal percutaneous internal fixation, but also to spinal open surgery under various pathological conditions.

[0074] It is worth noting that the above description is only a preferred embodiment of the present invention, and does not limit the scope of patent protection of the present invention. The present invention can also be replaced by equivalent technologies. Therefore, any equivalent changes made by using the description and illustrations of the present invention, or directly or indirectly applied to other related technical fields, are included in the scope of the present invention.

Claims

1. A pedicle screw suitable for spinal percutaneous internal fixation, comprising a rod, Features: It also includes a head connected to the rod; a fixing rod fastening structure is arranged on the head; the head includes a fixing rod clamping mechanism; the fixing rod clamping mechanism includes a first clamping arm and a second clamping arm; the first clamping arm and / or the second clamping arm are movably connected to the head; and it also includes a clamping arm fastening structure for fastening the first clamping arm to the second clamping arm; The portion of the head connected to the rod portion is a rod connecting section; when the fixing rod is clamped by the fixing rod clamping mechanism, the surface where the rod connecting section contacts the fixing rod is the inner surface of the rod connecting section; The inner surface of the rod connecting section matches the outer surface of the fixing rod; The first clamping arm and / or the second clamping arm are hinged to the rod connecting section; the first clamping arm and / or the second clamping arm hinged to the rod connecting section include an integral clamping arm, and the integral clamping arm is hinged to the rod connecting section via a pivot; the integral clamping arm is divided into two parts with the pivot as the dividing point: a first part and a second part; the integral clamping arm can rotate around the axis of the pivot so that the second part protrudes from the inner surface of the rod connecting section.

2. A pedicle screw suitable for spinal percutaneous fixation according to claim 1, Features: The fixed rod clamping mechanism includes an annular body; the annular body includes the first clamping arm and the second clamping arm; the first clamping arm and the second clamping arm are connected to form the annular body; the fixed rod fastening structure includes a fixed rod fastening hole; the annular body is provided with the fixed rod fastening hole that passes through the annular body, and the extension line of the axis of the fixed rod fastening hole extends into the ring formed by the annular body.

3. A pedicle screw suitable for spinal percutaneous fixation according to claim 2, Features: The fixing rod fastening hole is arranged on the first clamping arm and / or the second clamping arm.

4. A pedicle screw suitable for spinal percutaneous fixation according to claim 2, Features: The fixing rod fastening hole is formed by the first clamping arm and the second clamping arm being butted and spliced ​​together.

5. A pedicle screw suitable for spinal percutaneous fixation according to claim 2, Features: The annular body is provided with a force point for the opening and closing tool to apply force.

6. A pedicle screw suitable for spinal percutaneous fixation according to claim 5, Features: The force point is arranged on the first clamping arm and / or the second clamping arm.

7. A pedicle screw suitable for spinal percutaneous internal fixation according to claim 5, Features: The force-carrying point comprises a groove or a pin arranged on the annular body.

8. A pedicle screw suitable for spinal percutaneous internal fixation according to claim 5, Features: The clamping arm fastening structure comprises a fastening connector; the fastening connector is provided with a first fixing mechanism and a second fixing mechanism respectively; the first fixing mechanism is connected to the first clamping arm; and the second fixing mechanism is connected to the second clamping arm.

9. A pedicle screw suitable for spinal percutaneous internal fixation according to claim 8, Features: The first fixing mechanism includes a first fixing hole or a first fixing hook.

10. A pedicle screw suitable for spinal percutaneous internal fixation according to claim 9, Features: The second fixing mechanism includes a second fixing hook or a second fixing hole.

11. A pedicle screw suitable for spinal percutaneous internal fixation according to claim 2, Features: A first step structure is arranged at the butt end of the first clamping arm; and a second step structure matching the first step structure is arranged at the butt end of the second clamping arm.

12. A pedicle screw suitable for spinal percutaneous fixation according to claim 1, Features: A second portion surface is provided on the second portion; when the fixing rod is clamped by the fixing rod clamping mechanism, the second portion surface matches with the outer surface of the fixing rod.

13. A pedicle screw suitable for spinal percutaneous fixation according to claim 1, Features: The clamping arm fastening structure includes: in the assembled state, a first external thread is provided on the surface of the first clamping arm facing away from the second clamping arm; in the assembled state, a second external thread is provided on the surface of the second clamping arm facing away from the first clamping arm; the clamping arm fastening structure includes the first external thread and the second external thread.

14. A pedicle screw suitable for spinal percutaneous internal fixation according to claim 13, Features: The first clamping arm and the second clamping arm constitute a U-shaped fixed rod clamping mechanism; in the assembled state, a first internal thread is provided on the surface of the first clamping arm facing the second clamping arm; in the assembled state, a second internal thread is provided on the surface of the second clamping arm facing the first clamping arm; the fixed rod fastening structure includes the first internal thread and the second internal thread.

15. A pedicle screw suitable for spinal percutaneous internal fixation according to claim 14, Features: The fixing rod fastening structure includes a fixing rod fastening screw; the external thread of the fixing rod fastening screw matches the first internal thread and the second internal thread; the clamping arm fastening structure includes a clamping arm fixing nut; the internal thread of the clamping arm fixing nut matches the first external thread and the second external thread.

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