Distal femoral fracture plate screw combination internal fixation device and fixing method

Abstract

The present application relates to the technical field of femoral distal fracture fixation, in particular to a femoral distal fracture plate screw combination internal fixation device and a fixing method, the femoral distal fracture plate screw combination internal fixation device comprises: an outer locking plate arranged on the outer side of the distal end of the femur; an inner screw arranged from the inner side of the distal end of the femur; a distal locking hole, a first proximal locking hole and a second proximal locking hole are sequentially arranged on the outer locking plate from the distal end to the proximal end; the number of the first proximal locking hole is multiple, and the multiple first proximal locking holes are staggered arranged on the two side edges of the outer locking plate; and a sighting adjusting frame is used for adjusting and limiting the position and angle of the inner screw. The present application greatly reduces the operation difficulty of implantation, makes the implantation of the inner hollow screw more efficient and safe, and has strong technical repeatability.

Description

Technical Field

[0001] This invention relates to the field of distal femoral fracture fixation technology, specifically to an internal fixation device and fixation method using a combination of plates and screws for distal femoral fractures. Background Technology

[0002] A distal femoral fracture is a partial fracture of the distal femur near the knee joint, involving the epiphysis and apex. The distal femur is a key weight-bearing structure that maintains knee joint stability and movement, including the metaphysis, apex, and a series of ligaments and tendons.

[0003] The distal femur, as a weight-bearing joint, is prone to fractures, usually requiring surgical intervention for fixation. Treatment aims to restore length, alignment, and joint conformation, while reducing disability and mortality rates. Common surgical methods include locking plate and screw fixation and closed reduction with retrograde intramedullary nailing. Retrograde intramedullary nailing is often used for distal type A (AO / OTA classification system) or some type C1 fractures. A key consideration is that the distal intercondylar fossa must be intact, and there is a risk of knee ligament damage. For example, Chinese Patent Publication No. CN118319452A discloses an invention patent entitled "A Plate-Screw Internal Fixation Device for Treating Distal Femoral Fractures." Locking plate fixation is commonly used for most type B, C2 / 3 fractures, and periprosthetic fractures.

[0004] Traditional locking plate fixation devices for distal femoral fractures, especially type C fractures and periprosthetic fractures, often require enhanced medial support techniques for improved fixation. Currently, there are no specially designed anatomical medial distal femoral plates available clinically. Furthermore, medial plate fixation requires additional surgical incisions, potentially leading to prolonged surgery time and bleeding. It also increases the risk of postoperative infection and soft tissue injury to the medial aspect of the knee joint, particularly the risk of damage to the medial neurovascular bundle.

[0005] Existing techniques utilize lateral locking plates in conjunction with percutaneous medial column screws to fix distal femoral fractures, avoiding additional surgical approaches and costs. However, the screw insertion method lacks a fixed positioning tool, making it impossible to determine the insertion angle and depth, thus hindering positioning. This results in significant operational difficulties and poor technical repeatability. Furthermore, the screw layout on the plate is prone to interference with internal screws, further complicating screw insertion. Summary of the Invention

[0006] In order to solve at least one of the above-mentioned technical problems in the prior art, the present invention provides an internal fixation device and fixation method for distal femoral fractures using a combination of plates and screws.

[0007] To achieve the above objectives, the technical solution of the present invention is as follows:

[0008] In a first aspect, the present invention provides an internal fixation device for distal femoral fractures using a combination of plate and screws, comprising:

[0009] Lateral locking plate, placed on the lateral aspect of the distal femur;

[0010] The medial screw is inserted from the medial aspect of the distal femur.

[0011] The outer locking steel plate is provided with a distal locking screw hole, a first proximal locking screw hole, and a second proximal locking screw hole in sequence from the distal end to the proximal end; there are multiple first proximal locking screw holes, which are staggered on both sides of the outer locking steel plate.

[0012] The aiming adjustment bracket is used to adjust and limit the position and angle of the inner screw insertion.

[0013] Furthermore, there are multiple remote locking screw holes, which are spaced apart on both sides and the middle of the remote end of the outer locking steel plate.

[0014] Furthermore, there are multiple second proximal locking screw holes, which are arranged at linear intervals along the length direction of the outer locking steel plate.

[0015] Furthermore, a Kirschner wire guide hole is provided at the distal end of the outer locking steel plate.

[0016] Furthermore, the inner screw is a fully threaded hollow screw, with an external thread on the outer wall of the hollow screw and an internal thread on the internal through hole of the hollow screw, the internal thread and the external thread having opposite directions of rotation;

[0017] The plate and screw combination internal fixation device for distal femoral fractures also includes a connecting screw. The outer locking plate is provided with a pre-drilled hole for the connecting screw. After the connecting screw passes through the hollow screw and is threadedly connected to the hollow screw, the tip of the connecting screw is connected to the outer locking plate through the pre-drilled hole for the connecting screw.

[0018] Furthermore, the diameter of the hollow screw is 7mm, 7.3mm or 8mm.

[0019] Furthermore, the aiming adjustment frame includes a sight and an adjustment frame; the sight includes a fixed rod and a guide assembly, one end of the fixed rod is connected to the outer locking steel plate, and the other end of the fixed rod is rotatably connected to the guide assembly; one end of the adjustment frame is connected to the outer locking steel plate, and the other end of the adjustment frame is connected to the guide assembly.

[0020] The aiming adjustment frame is made of materials such as carbon fiber, polyamide plastic, or polycarbonate plastic, thereby avoiding interference with C-arm X-ray fluoroscopy during surgery.

[0021] Furthermore, a sight hole is provided at the far end of the outer locking steel plate, and one end of the fixing rod is fixedly connected to the outer locking steel plate through the sight hole.

[0022] Furthermore, an adjustment frame pre-drilled hole is provided near the outer locking steel plate. One end of the adjustment frame is fixedly connected to the outer locking steel plate through the adjustment frame pre-drilled hole, and the other end of the adjustment frame is rotatably connected to the guide assembly.

[0023] Furthermore, one end of the adjustment frame is fixedly connected to the outer locking steel plate through the second proximal locking screw hole, and the other end of the adjustment frame is fixedly connected to the guide assembly.

[0024] Furthermore, the guide assembly includes a guide, the other end of the fixing rod is rotatably connected to the guide, and the other end of the adjusting frame is fixedly connected to the guide;

[0025] The guide is provided with a guide hole, and the end of the guide hole near the outer locking steel plate has a step; an adjusting cylinder is provided in the guide hole, and a limiting plate is provided on the adjusting cylinder, which is embedded in the step; the outer end of the adjusting cylinder extending out of the guide hole is connected to a locking nut; a sleeve is provided in the adjusting cylinder, which is used for guiding and positioning when the hollow screw is inserted.

[0026] Secondly, the present invention provides a method for internal fixation of distal femoral fractures using a plate and screw combination, wherein the aforementioned internal fixation device for distal femoral fractures is used for fixation, and the method specifically includes:

[0027] S1. Reduce the fracture ends;

[0028] S2. Place the lateral locking plate on the lateral side of the distal femur, and use one or more of the distal locking screw hole, the first proximal locking screw hole, and the second proximal locking screw hole to drive in locking screws to fix the fracture ends of the distal femur.

[0029] S3. Connect the aiming device and the lateral locking plate. Select the connection position of the lateral locking plate and the adjustment frame according to the fracture type and the location of the fracture ends, and connect the lateral locking plate and the adjustment frame.

[0030] S4. Insert a Kirschner wire through the guide. After confirming that the position and length of the Kirschner wire are suitable through fluoroscopy, measure the length of the Kirschner wire and select a suitable hollow screw. Insert the hollow screw through the Kirschner wire channel from the medial condyle of the distal femur.

[0031] Further, in step S4, after fluoroscopy confirms that the position and length of the Kirschner wire are appropriate, and after the tip of the Kirschner wire passes through the mounting hole of the connecting screw on the steel plate, the length of the Kirschner wire is measured; a hollow screw is selected and inserted; intraoperative projection is performed again, and after the tip of the hollow screw is aligned with and close to the pre-drilled hole of the connecting screw, the Kirschner wire is removed, and a connecting screw is inserted through the hollow screw to connect the outer locking steel plate and the hollow screw.

[0032] Compared with the prior art, the present invention has the following beneficial effects:

[0033] The internal fixation device and fixation method for distal femoral fractures using a combination of plates and screws provided by this invention have three sets of screw holes on the outer locking plate. The first proximal locking screw hole is located in the middle and is staggered along the edge of the outer locking plate. This allows space to be left for the hollow screws to be inserted, avoids interference between the hollow screws and the locking screws, and also reduces the difficulty of inserting the hollow screws.

[0034] This invention incorporates a connecting screw within the hollow screw. This connecting screw passes through the hollow screw and connects to the outer locking plate, forming a triangular fixation structure that enhances the fixation effect. Furthermore, using a hollow screw results in minimal trauma, a low risk of postoperative infection, simple operation, and secure and effective fixation. Additionally, the opposite thread direction between the external thread of the hollow screw and the internal thread at the screw tip facilitates the removal of the internal hollow screw and the connecting screw after fracture healing.

[0035] The outer locking steel plate of the present invention is also connected to an aiming adjustment frame. The guide is fixed in one position by a fixing rod, and the guide has one degree of rotational freedom. The adjustment frame limits the rotational freedom of the guide. Specifically, the connection position between the adjustment frame and the outer locking steel plate determines the angle of the adjustment frame, which in turn determines the angle of the guide hole in the guide. Kirschner wires and hollow screws are inserted through the guide hole, which provides guidance and positioning for the insertion of hollow screws, greatly reducing the difficulty of insertion and making the insertion of inner hollow screws more efficient and safe, and the technology has strong repeatability. Attached Figure Description

[0036] Figure 1 This is a schematic diagram of the structure of Embodiment 1 of the present invention.

[0037] Figure 2 This is a schematic diagram of the outer locking steel plate in this invention.

[0038] Figure 3 This is a schematic diagram of the structure of the guide component in this invention.

[0039] Figure 4 This is a structural diagram for use in this invention.

[0040] Explanation of reference numerals in the attached figures:

[0041] 1. Outer locking steel plate; 101. Distal locking screw hole; 102. First proximal locking screw hole; 103. Second proximal locking screw hole; 104. Kirschner wire guide hole; 105. Pre-drilled hole for connecting screw; 106. Pre-drilled hole for sight; 107. Pre-drilled hole for adjustment bracket.

[0042] 2. Fixing rod; 3. Adjusting bracket; 4. Guide; 401. Guide hole; 5. Adjusting cylinder; 501. Limiting plate; 6. Locking nut; 601. Stepped hole; 7. Sleeve; 8. Hollow screw; 9. Connecting screw. Detailed Implementation

[0043] The technical solution of the present invention will be clearly described below with reference to the accompanying drawings. Obviously, the described embodiments are not all embodiments of the present invention. All other embodiments obtained by those skilled in the art without creative effort are within the protection scope of the present invention.

[0044] It should be noted that, unless otherwise specifically stated, the relative arrangement and numerical expressions of the components and steps described in these embodiments should not be construed as limiting the scope of the invention.

[0045] The following description of exemplary embodiments is merely illustrative and is not intended to limit the invention or its application or use in any way. Techniques, methods, and apparatus known to those skilled in the art may not be discussed in detail herein, but where applicable, such techniques, methods, and apparatus should be considered part of this specification.

[0046] Example 1

[0047] This embodiment provides an internal fixation device combining plate and screws for distal femoral fractures, such as... Figure 1 As shown, it includes:

[0048] Lateral locking plate 1 is placed on the lateral aspect of the distal femur; lateral locking plate 1 is an anatomical plate made of demagnetized titanium alloy.

[0049] The medial screw is inserted from the medial aspect of the distal femur.

[0050] like Figure 2 As shown, the outer locking steel plate 1 is provided with a distal locking screw hole 101, a first proximal locking screw hole 102, and a second proximal locking screw hole 103 in sequence from the distal end to the proximal end; there are multiple first proximal locking screw holes 102, and multiple first proximal locking screw holes 102 are staggered on both sides of the outer locking steel plate 1.

[0051] The number of the distal locking screw holes 101 is multiple, and the multiple distal locking screw holes 101 are spaced apart on both sides and the middle of the distal end of the outer locking steel plate 1. Figure 2 The diagram shows six remote locking screw holes 101, which are arranged in an alternating pattern.

[0052] There are multiple second proximal locking screw holes 103, which are arranged at linear intervals along the length of the outer locking steel plate 1. Both the first proximal locking screw hole 102 and the second proximal locking screw hole 103 are double holes, that is, each screw hole consists of two closely spaced circular holes, which can be used to insert ordinary tension screws and locking screws.

[0053] Two Kirschner wire guide holes 104 are also provided at the far end of the outer locking steel plate 1, and the two Kirschner wire guide holes 104 are respectively provided on both sides of the far end of the outer locking steel plate 1.

[0054] like Figure 4 As shown, the inner screw is a hollow screw 8, made of demagnetized titanium alloy, with a diameter of 7mm, 7.3mm, or 8mm; the outer wall of the hollow screw 8 is provided with an external thread, which is a full thread; the hollow screw 8 has a through hole inside, and an internal thread is provided on the internal through hole. The internal thread can be a full thread, or it can be provided on the inner wall of the tip of the internal through hole. The internal thread and the external thread have opposite directions of rotation.

[0055] The internal fixation device for distal femoral fractures using a plate and screw combination also includes a connecting screw 9. A pre-drilled hole 105 for the connecting screw is provided on the outer locking plate 1. After the connecting screw 9 passes through the hollow screw 8 and is threadedly connected to the hollow screw, the tip of the connecting screw 9 is connected to the outer locking plate 1 through the pre-drilled hole 105, thereby connecting the outer locking plate 1 and the hollow screw 8 inserted on the inner side into a structurally stable whole.

[0056] The external thread of the connecting screw 9 is a full thread, and both ends of the connecting screw 9 are provided with hexagonal countersunk heads, so both ends of the connecting screw 9 can be matched with disassembly tools (such as hex wrenches and hex screwdrivers), which facilitates the removal and installation of the connecting screw 9.

[0057] In addition, such as Figure 1As shown, the internal fixation device for distal femoral fractures using a plate and screw combination also includes an aiming adjustment frame. The aiming adjustment frame is made of materials such as carbon fiber, polyamide plastic, or polycarbonate plastic, thus avoiding interference with C-arm fluoroscopy during surgery. The aiming adjustment frame includes a sight and an adjustment frame 3; the sight includes a fixing rod 2 and a guide assembly. One end of the fixing rod 2 is connected to the outer locking plate 1, and the other end of the fixing rod 2 is rotatably connected to the guide assembly; one end of the adjustment frame 3 is connected to the outer locking plate 1, and the other end of the adjustment frame 3 is connected to the guide assembly.

[0058] One end of the fixed rod 2 is connected to a rotating shaft, which extends tangentially to the fixed rod 2. A guide 4 is mounted on the rotating shaft, allowing the guide 4 to be rotatably connected to the fixed rod 2. A sight pre-drilled hole 106 is provided at the distal end of the outer locking steel plate 1. One end of the fixed rod 2 is fixedly connected to the outer locking steel plate 1 through the sight pre-drilled hole 106. In this embodiment, the sight pre-drilled hole 106 is a universal joint, meaning the sight can be adjusted arbitrarily within a certain angle relative to the outer locking steel plate 1.

[0059] There are two ways to connect the outer locking steel plate 1 and the adjusting frame 3, and the one in this embodiment is:

[0060] One end of the adjusting bracket 3 is fixedly connected to the outer locking steel plate 1 through the second proximal locking screw hole 103, and the other end of the adjusting bracket 3 is fixedly connected to the guide assembly. By connecting the adjusting bracket 3 to the second proximal locking screw hole 103 at different positions, the guiding angle of the guide assembly changes accordingly, thereby adjusting the insertion angle of the hollow screw 8.

[0061] According to the adjustment angle requirements of the hollow screw 8, such as the adjustment ratio, the interval distance of the second proximal locking screw hole 103 is set.

[0062] The outer locking steel plate 1 has a pre-drilled hole 107 for adjusting the frame near its proximal end. One end of the adjusting frame 3 can be fixedly connected to the outer locking steel plate 1 through the pre-drilled hole 107, and the other end of the adjusting frame 3 is rotatably connected to the guide assembly. Since the outer locking steel plate 1 and the adjusting frame 3 are connected through the pre-drilled hole 107 and the position of the adjusting frame 3 is fixed, if the guiding angle of the guide assembly needs to be adjusted, the guide assembly needs to be manually rotated due to the rotatable connection between the guide assembly and the adjusting frame 3.

[0063] like Figure 1 and Figure 3 As shown, the guide assembly includes a guide 4, the other end of the fixed rod 2 is rotatably connected to the guide 4, and the other end of the adjusting frame 3 is fixedly connected to the guide 4;

[0064] The guide 4 is provided with a guide hole 401. One end of the guide hole 401 near the outer locking steel plate 1 has a step. An adjusting cylinder 5 is provided in the guide hole 401. A limiting plate 501 is provided on the adjusting cylinder 5 and is embedded in the step. The other end of the adjusting cylinder 5 extends out of the guide hole 401. A locking nut 6 is connected to the outside of the adjusting cylinder 5. A stepped hole 601 is provided inside the locking nut 6. An internal thread is provided on the inner wall of the stepped hole 601. An external thread is provided on the outer wall of the adjusting cylinder 5. The adjusting cylinder 5 and the locking nut 6 are threadedly connected to achieve a tight connection between the adjusting cylinder 5 and the guide 4.

[0065] A sleeve 7 is provided inside the adjusting cylinder 5, which is used for guiding and positioning the hollow screw 8 during insertion. A handle is also provided at the outer end of the sleeve 7 to facilitate insertion.

[0066] The outer locking steel plate 1 in this embodiment is different from the locking steel plate or liss steel plate in the prior art. The outer locking steel plate 1 provided in this embodiment utilizes the layout of the first proximal locking screw hole 102 to avoid the insertion space of the hollow screw 8, which greatly reduces the difficulty of inserting the hollow screw 8.

[0067] The distal and proximal ends of the lateral locking plate 1 are provided with mounting holes for the aiming adjustment frame. After the fracture is reduced, the distal and proximal ends of the lateral locking plate 1 are fixed with screws, and the distal aiming device and the proximal adjustment frame 3 are installed respectively. The aiming device is fixed in position, while the adjustment frame 3 is relatively flexible in position. On the one hand, it can form a triangular combination structure for the installation structure of the guide 4, which is stable and the guide 4 is not easy to move when inserted, and is not easily damaged in long-term use. On the other hand, the guiding angle of the guide 4 can be adjusted by flexibly adjusting the adjustment frame 3.

[0068] The specific adjustment principle is as follows:

[0069] After the sight is fixed to the outer locking steel plate 1, the guide 4 is fixed in position. According to the structural design, the position of the guide 4 is such that the axis of the guide hole is located in the insertion surface of the hollow screw 8. In addition, the guide 4 can rotate axially along the rotation axis. Then, the adjustment bracket 3 is installed. According to the insertion angle of the hollow screw 8, the mounting screw hole of the adjustment bracket 3 is selected and the adjustment bracket 3 is fixed. If the installation position of the adjustment bracket 3 is different, the installation angle between the fixing rod 2 and the outer locking steel plate 1 is finely adjusted so that the position of the guide 4 rotates to the near end or the far end by a certain position, thereby meeting the installation requirements of the adjustment bracket 3. Subsequently, the angle of the guide hole 401 changes, thereby realizing the adjustment of the insertion angle.

[0070] To facilitate the selection of the mounting screw hole of the adjustment bracket 3, the insertion angle can be set on one side of the second proximal locking screw hole 103. For example, it can be set by label or engraving, which makes it easier for the operator to quickly select the insertion angle.

[0071] Example 2

[0072] This embodiment provides a method for internal fixation of distal femoral fractures using a plate and screw combination. The method specifically includes:

[0073] S1. Lateral incision for distal femoral fracture, reduction of fracture ends;

[0074] S2. After the fracture ends are properly aligned, place the lateral locking plate 1 on the lateral side of the distal femur and use one or more of the distal locking screw hole 101, the first proximal locking screw hole 102, and the second proximal locking screw hole 103 to drive in locking screws to fix the fracture ends of the distal femur.

[0075] S3. Connect the aiming device and the outer locking plate 1. Select the connection position of the outer locking plate 1 and the adjustment frame according to the fracture type and the location of the fracture ends, and connect the outer locking plate 1 and the adjustment frame.

[0076] S4. Insert a Kirschner wire through the guide. After fluoroscopy confirms that the position and length of the Kirschner wire are appropriate and that the tip of the Kirschner wire passes through the pre-drilled hole 105 for the connecting screw, measure the length of the Kirschner wire. Based on this, select a hollow screw 8 of appropriate length and size and insert it through the Kirschner wire channel into the medial condyle of the distal femur. Project again during the operation. After confirming that the tip of the hollow screw is aligned with and close to the pre-drilled hole 105 for the connecting screw, remove the Kirschner wire and insert a connecting screw 9 through the hollow screw 8 to connect the lateral locking plate 1 and the hollow screw 8.

[0077] The above specific embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Although the present invention has been described in detail with reference to examples, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the scope of the technical solutions of the present invention, and all such modifications or substitutions should be covered within the scope of the claims of the present invention.

Claims

1. A plate and screw combination internal fixation device for distal femoral fractures, characterized in that, include: Lateral locking plate, placed on the lateral aspect of the distal femur; The medial screw is inserted from the medial aspect of the distal femur. The outer locking steel plate is provided with a distal locking screw hole, a first proximal locking screw hole, and a second proximal locking screw hole in sequence from the distal end to the proximal end; there are multiple first proximal locking screw holes, which are staggered on both sides of the outer locking steel plate. The aiming adjustment bracket is used to adjust and limit the position and angle of the inner screw insertion. The aiming adjustment frame includes a sight and an adjustment frame; the sight includes a fixed rod and a guide assembly, one end of the fixed rod is connected to an outer locking steel plate, and the other end of the fixed rod is rotatably connected to the guide assembly; one end of the adjustment frame is connected to the outer locking steel plate, and the other end of the adjustment frame is connected to the guide assembly. One end of the adjustment frame is fixedly connected to the outer locking steel plate through the second proximal locking screw hole, and the other end of the adjustment frame is fixedly connected to the guide assembly; The guide assembly includes a guide, the other end of the fixed rod is rotatably connected to the guide, and the other end of the adjusting frame is fixedly connected to the guide; The guide is provided with a guide hole, and the end of the guide hole near the outer locking steel plate has a step; an adjusting cylinder is provided in the guide hole, and a limiting plate is provided on the adjusting cylinder, which is embedded in the step; the outer end of the adjusting cylinder extending out of the guide hole is connected to a locking nut; a sleeve is provided in the adjusting cylinder, which is used for guiding and positioning when the hollow screw is inserted.

2. The internal fixation device for distal femoral fractures using a plate and screw combination according to claim 1, characterized in that, The number of distal locking screw holes is multiple, and the multiple distal locking screw holes are spaced apart at both sides and the middle of the distal end of the outer locking steel plate; The number of second proximal locking screw holes is multiple, and the multiple second proximal locking screw holes are arranged at linear intervals along the length direction of the outer locking steel plate.

3. The internal fixation device for distal femoral fractures using a plate and screw combination according to claim 1, characterized in that, The inner screw is a hollow screw, with an external thread on the outer wall of the hollow screw and an internal thread on the internal through hole of the hollow screw. The internal thread and the external thread have opposite directions of rotation. The plate and screw combination internal fixation device for distal femoral fractures also includes a connecting screw. The outer locking plate is provided with a pre-drilled hole for the connecting screw. After the connecting screw passes through the hollow screw and is threadedly connected to the hollow screw, the tip of the connecting screw is connected to the outer locking plate through the pre-drilled hole for the connecting screw.

4. The internal fixation device for distal femoral fractures using a plate and screw combination according to claim 1, characterized in that, The outer locking steel plate has a sight hole at its far end, and one end of the fixing rod is fixedly connected to the outer locking steel plate through the sight hole.

5. The internal fixation device for distal femoral fractures using a plate and screw combination according to claim 1, characterized in that, The outer locking steel plate has a pre-drilled hole for the adjustment frame near its end. One end of the adjustment frame is fixedly connected to the outer locking steel plate through the pre-drilled hole, and the other end of the adjustment frame is rotatably connected to the guide assembly.

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