Proximal femoral fracture intramedullary fixation device

Abstract

The present invention discloses a proximal femoral fracture intramedullary fixation device, comprising a proximal femoral anchoring support, a femoral intramedullary nail and a proximal locking nail of the intramedullary nail, wherein the proximal femoral anchoring support and the femoral intramedullary nail are connected by the proximal locking nail of the intramedullary nail; the proximal femoral anchoring support of the present application can be made by an integrated molding process, therefore, it has better mechanical strength, is not easy to break, and can significantly reduce the incidence of internal fixation failure. The proximal femoral anchoring support of the present application can be closely and fully attached to the cortical bones around the proximal femur, especially to the medial cortex, therefore, the proximal femoral anchoring support can fully support the surrounding cortex, especially the supporting effect on the medial cortex, which is crucial for the sustained stability after fracture surgery. The contact area between the body of the proximal femoral anchoring support and the femoral intramedullary nail is large, which can significantly reduce the effect of stress concentration and reduce the probability of fracture at the contact part between the two.

Description

Technical Field

[0001] The invention relates to medical supplies, in particular to an intramedullary fixation device for proximal femoral fractures. Background Art

[0002] 1. With the development of an aging society, there are many patients with proximal femoral fractures in my country every year. The internal fixation treatments include bone plates, DHS, PFN, PFNA, and InterTAN.

[0003] At present, PFNA is more common and is the representative of intramedullary fixation. The advantages of PFNA are: intramedullary fixation, shorter force arm than extramedullary fixation, better mechanical properties; spiral blade implant can achieve anti-rotation and angular stability.

[0004] 2. The existing proximal femoral fixation device mainly consists of a main nail installed in the femoral shaft medullary and a secondary nail installed in the femoral neck. Among them, the main nail needs to be provided with a through hole along the axial direction of the femoral neck. The through hole is oblique to conform to the structure of the proximal femur, and the secondary nail is inserted into the oblique through hole to complete the installation of the device. Disadvantages of the existing technology:

[0005] a. It is ineffective for some cases, such as comminuted fracture of the proximal lateral cortex of the femur or osteoporosis. This is because when the intramedullary nail is placed, the proximal lateral cortex of the femur will split on the coronal plane and the medullary nail will slip out, that is, the proximal bone cannot contain the proximal end of the medullary nail.

[0006] b. Design flaws. One of the features of the PFNA design is that it allows the spiral blade to slide outward along the hole of the intramedullary nail, creating a pressure effect on the femoral neck and femoral trochanter, promoting fracture healing, but it also causes femoral neck shortening, the spiral blade to withdraw, and the tail of the spiral blade to rub against the iliotibial band, causing snapping and pain.

[0007] c. Cutting of the femoral head cannot be completely avoided, including oblique upward cutting toward the weight-bearing area and "central" cutting. Some authors point out that "central" cutting is an important reason for the failure of PFNA. The reason for this phenomenon is that the secondary nail (spiral blade) needs to pass through the through hole of the main nail. For easy installation, the secondary nail can only be designed to be circular or quasi-circular, and the diameter cannot be too large.

[0008] d. It is very difficult to reduce and insert the medullary nail when using PFNA in cases of subtrochanteric fractures. Subtrochanteric fractures are defined as femoral shaft fractures with the main fracture line within 5 cm distal to the lesser trochanter of the femur. Due to the special anatomical and biomechanical characteristics of this area, subtrochanteric fractures are difficult to reduce and the risk of internal fixation failure is very high. The subtrochanteric area is the transition point from the femoral neck to the femoral shaft. Structurally, it is the area where cancellous bone transitions to cortical bone. Its cortex is thinner than other parts of the femoral shaft. It is a stress concentration point in biomechanics. Most fractures are comminuted and often accompanied by medial cortical defects. There are many powerful muscle groups attached to the subtrochanteric area of ​​the femur. The proximal femur has the abductors, external rotators and iliopsoas of the hip joint, and the distal femur has the adductors and flexors. Once a fracture occurs, the original muscle balance will be destroyed and complex displacement will occur. Due to the traction of the abductors, external rotators and iliopsoas muscles, the proximal end of the fracture is abducted, externally rotated and flexed, while the distal end is shortened, adducted and displaced due to the strong traction of the flexors and adductors. Such complex stress leads to difficulties in clinical reduction and fixation. During reduction, the distal end should be abducted and externally rotated, but the abduction of the lower limbs will inevitably lead to difficulties in PFNA insertion. PFNA only has a certain degree of support for cases with medial cortical defects, and patients with subtrochanteric fractures will still experience internal fixation fractures. The pressure effect brought by the sliding of the spiral blade only promotes the accelerated healing between the femoral neck and the femoral trochanter, so the PFNA treatment effect is not good for cases with medial cortical defects. Summary of the invention

[0009] The purpose of the present invention is to provide an intramedullary fixation device for proximal femoral fractures to solve the above-mentioned technical problems existing in the prior art.

[0010] The intramedullary fixation device for proximal femoral fracture provided by the present invention comprises a proximal femoral anchoring support, a femoral intramedullary nail and a proximal intramedullary nail locking nail, wherein the proximal femoral anchoring support and the femoral intramedullary nail are connected via the proximal intramedullary nail locking nail;

[0011] The proximal femoral anchoring support body comprises a head and a body; the head extends a neck for connecting with the body, an I-shaped blade is mounted on the head, and the body is a tapered body that is wide at the top and narrow at the bottom;

[0012] The head, neck and body are provided with Kirschner wire guide holes penetrating each other, and the Kirschner wire guide hole of the body is provided with a thread;

[0013] The body is provided with a mounting hole opened longitudinally, an elliptical segment is provided in the mounting hole, the femoral intramedullary nail is installed in the body through the mounting hole, a boss matching the elliptical segment is provided on the femoral intramedullary nail, and both ends of the femoral intramedullary nail extend to the outside of the body respectively;

[0014] The femoral intramedullary nail is provided with a proximal locking hole, and the proximal locking nail of the intramedullary nail is screwed into the Kirschner wire guide hole in the body and passes through the proximal locking hole on the femoral intramedullary nail;

[0015] The femoral intramedullary nail is provided with a distal locking hole, and the distal locking nail of the intramedullary nail is arranged in the distal locking hole.

[0016] Furthermore, a plurality of cross-arranged proximal femoral cortex locking screws are mounted on the body.

[0017] Furthermore, the body is provided with a plurality of cross-arranged through holes, and a plurality of the proximal femoral cortex locking screws are threadedly connected to the through holes.

[0018] Furthermore, a cross-shaped slot is provided at the bottom of the body, and the cross-section of the slot is V-shaped.

[0019] Furthermore, a thread for connecting a slide hammer is provided on the top of the femoral intramedullary nail.

[0020] Furthermore, a threaded section for connecting a slide hammer is provided on the elliptical section of the mounting hole.

[0021] Furthermore, the head and the body form an angle of 130 degrees, and the proximal locking hole and the axis of the femoral intramedullary nail form an angle of 130 degrees.

[0022] Furthermore, the proximal locking hole is a circular hole, and the distal locking hole is a square slot hole.

[0023] Furthermore, the medial curve of the proximal femur anchoring support is consistent with the curve of the medial cortex of the proximal femur.

[0024] Furthermore, the proximal locking nail of the intramedullary nail comprises a rod body segment and a threaded segment arranged at the end of the rod body segment, and a hexagonal groove is arranged on the end surface of the threaded segment.

[0025] The intramedullary fixation device for proximal femoral fracture provided by the present invention has the following advantages:

[0026] 1. The proximal femoral anchoring support of the present application can be manufactured by an integrated molding process, and therefore has better mechanical strength, is not easy to break, and can significantly reduce the incidence of internal fixation failure.

[0027] 2. The proximal femoral anchoring support body of the present application can be tightly and fully attached to the cortical bones around the proximal femur, especially to the medial cortex. Therefore, the proximal femoral anchoring support body can fully support the surrounding cortices, especially the medial cortex, which is crucial for the sustained stability after fracture surgery.

[0028] 3. The inner curve of the proximal femoral anchoring support is consistent with the curve of the inner cortex of the proximal femur, and can be fully attached to the inner cortex of the proximal femur. This close attachment makes it impossible for the I-shaped blade to move along the axis of the femoral neck toward the acetabulum and then cut the femoral head, which can minimize the "central" cutting.

[0029] 4. The contact area between the body of the proximal femoral anchoring support and the femoral intramedullary nail is very large, which can significantly reduce the effect of stress concentration and reduce the probability of fracture at the contact point between the two.

[0030] 5. The design concept and usage of this patent determine that the width of the I-shaped blade is not limited by other aspects, but only by the femoral neck diameter of the patient. The wide width of the I-shaped blade can make it closer to the cortical bone. Because the cortical bone is "harder" than the cancellous bone, it has better mechanical advantages in anti-rotation and anti-pullout.

[0031] 6. The unique design of the I-shaped blade has a good effect in preventing the proximal femur from rotating, and can minimize the cutting of the femoral head in the oblique inner and upper direction. The I-shaped blade has a small cross-sectional area, and causes less damage to the bone and blood supply when it is inserted, making it less likely for femoral head necrosis to occur. It can also squeeze the cancellous bone into the surrounding cortex, making the bone denser. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] In order to more clearly illustrate the specific implementation methods of the present invention or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0033] Figure 1 A schematic diagram of the structure of the intramedullary fixation device for proximal femoral fracture provided in Embodiment 1 of the present invention;

[0034] Figure 2 A schematic diagram of the structure of a proximal femur anchoring support body provided in the first embodiment of the present invention from a first viewing angle;

[0035] Figure 3 A schematic diagram of the structure of the proximal femur anchoring support body provided in the first embodiment of the present invention from a second viewing angle;

[0036] Figure 4 A schematic diagram of the structure of the proximal femur anchoring support body provided in the first embodiment of the present invention from a third perspective;

[0037] Figure 5 A schematic diagram of the structure of the proximal femur anchoring support body provided in the fourth perspective according to the first embodiment of the present invention;

[0038] Figure 6 A schematic diagram of the structure of the proximal femoral anchoring support and the proximal femoral cortical locking screw provided in the first embodiment of the present invention from a first perspective;

[0039] Figure 7 A schematic diagram of the structure of the proximal femoral anchoring support and the proximal femoral cortex locking screw from a second perspective provided in the first embodiment of the present invention;

[0040] Figure 8 A schematic diagram of the structure of a femoral intramedullary nail provided in Embodiment 1 of the present invention;

[0041] Fig. 9 A schematic diagram of the structure of the proximal locking nail of the intramedullary nail provided in the first embodiment of the present invention;

[0042] Fig.10 This is a schematic structural diagram of an I-shaped blade provided in Example 1 of the present invention.

[0043] Figure markings: 1-proximal femoral anchoring support; 2-femoral intramedullary nail; 3-proximal intramedullary nail locking nail; 11-head; 12-body; 13-neck; 4-I-shaped blade; 5-Kirschner wire guide hole; 6-mounting hole; 21-boss; 7-distal intramedullary nail locking nail; 8-proximal femoral cortical locking screw; 121-through hole; 9-slot; 31-rod segment; 32-threaded segment. DETAILED DESCRIPTION

[0044] The technical solution of the present invention will be described clearly and completely below in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0045] In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second", and "third" are used for descriptive purposes only, and cannot be understood as indicating or implying relative importance.

[0046] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0047] Embodiment 1:

[0048] Figure 1 A schematic diagram of the structure of the intramedullary fixation device for proximal femoral fracture provided in Embodiment 1 of the present invention; Figure 2 A schematic diagram of the structure of a proximal femur anchoring support body provided in the first embodiment of the present invention from a first viewing angle; Figure 3 A schematic diagram of the structure of the proximal femur anchoring support body provided in the first embodiment of the present invention from a second viewing angle; Figure 4 A schematic diagram of the structure of the proximal femur anchoring support body provided in the first embodiment of the present invention from a third perspective; Figure 5 A schematic diagram of the structure of the proximal femur anchoring support body provided in the fourth perspective according to the first embodiment of the present invention; Figure 6 A schematic diagram of the structure of the proximal femoral anchoring support and the proximal femoral cortical locking screw provided in the first embodiment of the present invention from a first perspective; Figure 7 A schematic diagram of the structure of the proximal femoral anchoring support and the proximal femoral cortex locking screw from a second perspective provided in the first embodiment of the present invention; Figure 8 A schematic diagram of the structure of a femoral intramedullary nail provided in Embodiment 1 of the present invention; Fig. 9 A schematic diagram of the structure of the proximal locking nail of the intramedullary nail provided in the first embodiment of the present invention; Fig.10 Schematic diagram of the structure of the I-shaped blade provided in the first embodiment of the present invention; Figure 1-Figure 10 As shown, the proximal femoral fracture intramedullary fixation device provided in the first embodiment of the present invention comprises a proximal femoral anchoring support body 1, a femoral intramedullary nail 2 and a proximal intramedullary nail locking nail 3, wherein the proximal femoral anchoring support body 1 and the femoral intramedullary nail 2 are connected via the proximal intramedullary nail locking nail 3;

[0049] The proximal femoral anchoring support body 1 comprises a head 11 and a body 12; the head 11 extends a neck 13 for connecting with the body 12, an I-shaped blade 4 is mounted on the head 11, and the body 12 is a conical body that is wide at the top and narrow at the bottom;

[0050] The head 11, the neck 13 and the body 12 are provided with a Kirschner wire guide hole 5 which penetrates each other. The Kirschner wire guide hole 5 of the body 12 is provided with a thread, and the thread has three functions: ① connecting a hollow handle for holding, and knocking the proximal femoral anchoring support body so that it is placed into the bone along the Kirschner wire; ② connecting an aimer, and the aimer is used to place the distal locking screw of the intramedullary nail; ③ locking the proximal locking screw of the intramedullary nail, and the thread is adapted to the thread of the proximal locking screw of the intramedullary nail, and can be locked with each other, so as to statically lock the femoral intramedullary nail.

[0051] The body 12 is provided with a longitudinally opened mounting hole 6, an elliptical segment is provided in the mounting hole 6, the femoral intramedullary nail 2 is installed in the body 12 through the mounting hole 6, the femoral intramedullary nail 2 is provided with a boss 21 matching with the elliptical segment, and both ends of the femoral intramedullary nail 2 extend to the outside of the body 12 respectively;

[0052] A proximal locking hole is provided on the femoral intramedullary nail 2, and the proximal locking nail 3 of the intramedullary nail is screwed into the Kirschner wire guide hole 5 in the body 12 and passes through the proximal locking hole on the femoral intramedullary nail 2. The proximal locking nail 3 of the intramedullary nail is used to prevent the femoral intramedullary nail 2 from sliding up and down in the mounting hole 6.

[0053] The femoral intramedullary nail 2 is provided with a distal locking hole, and a distal locking nail 7 of the intramedullary nail is arranged in the distal locking hole.

[0054] Specifically, a plurality of cross-arranged proximal femoral cortex locking screws 8 are mounted on the body 12 .

[0055] Specifically, the body 12 is provided with a plurality of cross-arranged through holes 121 , and a plurality of the proximal femoral cortex locking screws 8 are threadedly connected to the through holes 121 .

[0056] The proximal femoral cortical locking screw 8 is used to fix the proximal femoral front and rear cortical bones to the body 12 of the proximal femoral anchoring support 1. The proximal femoral cortical locking screw 8 can be used to fix the proximal femoral anchoring support 1 more stably into a whole; and a plurality of proximal femoral cortical locking screws 8 are arranged crosswise to limit the movement of the proximal femoral anchoring support 1 in all directions. Therefore, the proximal femoral cortical locking screw 8 has the function of preventing the I-shaped blade 4 from cutting or withdrawing from the femoral head and femoral neck.

[0057] Specifically, a cross-shaped slot 9 is provided at the bottom of the body 12 , and the cross section of the slot 9 is V-shaped.

[0058] The cross section of the slot 9 is V-shaped, which is convenient for inserting the femoral intramedullary nail 2. The outer groove is deeper and is used to observe the situation of the femoral intramedullary nail 2 in the proximal femoral anchoring support 1 and take appropriate measures.

[0059] Specifically, a thread for connecting a slide hammer is provided at the top of the femoral intramedullary nail 2, and the slide hammer is used for removal.

[0060] Specifically, a thread for connecting a slide hammer is provided on the elliptical section of the mounting hole 6. The slide hammer is used for femoral head replacement and is removed from the proximal end of the femur along the longitudinal axis after the femoral neck is cut off.

[0061] Specifically, the head 11 and the body 12 form an angle of 130 degrees, which is slightly larger than the average value of the femoral neck-shaft angle of 127 degrees, and the proximal locking hole and the axis of the femoral intramedullary nail 2 form an angle of 130 degrees.

[0062] Specifically, the proximal locking hole is a circular hole, and the distal locking hole is a square slot hole.

[0063] Specifically, the inner curve of the proximal femoral anchoring support body 1 is consistent with the curve of the inner cortex of the proximal femur.

[0064] Specifically, the proximal locking nail 3 of the intramedullary nail includes a rod section 31 and a threaded section 32 arranged at the end of the rod section 31. The end surface of the threaded section 32 is provided with a hexagonal groove for easy use when removing the proximal locking nail 3 of the intramedullary nail.

[0065] The method of using the intramedullary fixation device for proximal femoral fracture of the present application is as follows:

[0066] Case selection: Proximal femoral fractures include fractures of the femoral neck, intertrochanteric ...

[0067] The present application is applicable to the treatment of unstable proximal femoral fractures, such as comminuted fractures of the medial or lateral cortex of the proximal femur, subtrochanteric fractures, and unstable proximal femoral fractures for which other fixation systems are poorly effective.

[0068] After cutting the soft tissue on the proximal lateral side of the thigh and exposing the lateral cortex between the greater and lesser trochanters of the femur, the guide Kirschner wire is inserted according to the patient's anteversion angle and neck-shaft angle. The guide Kirschner wire is ensured to be in the best position by fluoroscopy, that is, it is located below the center on the anteroposterior film and in the center on the lateral film. A special window-opening bone knife is used to open a window on the lateral cortex along the guide Kirschner wire. After opening the window, the femoral intramedullary nail 2 is inserted into the distal medullary cavity. The proximal femoral cancellous bone is evaluated. If the cancellous bone is dense and has a large amount of bone, it should be removed as appropriate to facilitate the placement of the proximal femoral anchoring support 1. The proximal femoral anchoring support 1 is placed along the guide Kirschner wire, and a hollow screwdriver is connected for holding and striking. The proximal femoral anchoring support 1 is placed in the proximal femoral bone by striking. Be careful not to strike too deep. Strike when necessary to avoid artificial withdrawal due to excessive depth. Artificial withdrawal will reduce its anchoring function. The removed cancellous bone is implanted in the medial cortical defect or other fracture. If osteoporosis is considered, the proximal femoral cortical locking screw 8 can be used to fix the anterior and posterior cortical bones of the proximal femur and lock them to the proximal femoral anchoring support 1 if necessary.

[0069] When the body 12 of the proximal femoral anchoring support 1 is parallel to the femoral medullary cavity, confirm with perspective if necessary, slide the femoral intramedullary nail 2 proximally, place it into the mounting hole 6 of the proximal femoral anchoring support 1, and after it reaches the predetermined position, connect the aimer and place the distal locking nail 7 of the intramedullary nail. Remove the aimer and place the proximal intramedullary locking nail 3. Replant the bone block removed during the window opening at the outer cortical window opening. Suture the soft tissue and the operation is over.

[0070] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A proximal femoral fracture intramedullary fixation device, characterized in that: It comprises a proximal femoral anchoring support, a femoral intramedullary nail and a proximal intramedullary nail locking nail, wherein the proximal femoral anchoring support and the femoral intramedullary nail are connected via the proximal intramedullary nail locking nail; The proximal femoral anchoring support body comprises a head and a body; The head extends out a neck for connecting with the body, an I-shaped blade is mounted on the head, and the body is a tapered body that is wide at the top and narrow at the bottom; The head, neck and body are provided with Kirschner wire guide holes penetrating each other, and the Kirschner wire guide hole of the body is provided with a thread; The body is provided with a mounting hole opened longitudinally, an elliptical segment is provided in the mounting hole, the femoral intramedullary nail is installed in the body through the mounting hole, a boss matching the elliptical segment is provided on the femoral intramedullary nail, and both ends of the femoral intramedullary nail extend to the outside of the body respectively; The femoral intramedullary nail is provided with a proximal locking hole, and the proximal locking nail of the intramedullary nail is screwed into the Kirschner wire guide hole in the body and passes through the proximal locking hole on the femoral intramedullary nail; The femoral intramedullary nail is provided with a distal locking hole, and the distal locking nail of the intramedullary nail is arranged in the distal locking hole; The body is provided with a plurality of cross-arranged proximal femoral cortex locking screws; The body is provided with a plurality of cross-arranged through holes, and a plurality of the proximal femoral cortex locking screws are threadedly connected to the through holes; The proximal femoral cortical locking screw is used to fix the proximal femoral anterior and posterior cortical bones and the body of the proximal femoral anchoring support body; A cross-shaped slot is provided at the bottom of the body.

2. The intramedullary fixation device for proximal femoral fracture according to claim 1, characterized in that: The cross section of the groove is V-shaped.

3. The intramedullary fixation device for proximal femoral fracture according to claim 1, characterized in that: The top of the femoral intramedullary nail is provided with a thread for connecting a slide hammer.

4. The intramedullary fixation device for proximal femoral fracture according to claim 1, characterized in that: The elliptical section of the mounting hole is provided with a thread for connecting a slide hammer.

5. The intramedullary fixation device for proximal femoral fracture according to claim 1, characterized in that: The head and the body form an angle of 130 degrees, and the proximal locking hole and the axis of the femoral intramedullary nail form an angle of 130 degrees.

6. The intramedullary fixation device for proximal femoral fracture according to claim 1, characterized in that: The proximal locking hole is a circular hole, and the distal locking hole is a square slot hole.

7. The intramedullary fixation device for proximal femoral fracture according to claim 1, characterized in that: The inner curve of the proximal femoral anchoring support is consistent with the curve of the inner cortex of the proximal femur.

8. The intramedullary fixation device for proximal femoral fracture according to claim 1, characterized in that: The proximal locking nail of the intramedullary nail comprises a rod body section and a threaded section arranged at the end of the rod body section, and a hexagonal groove is arranged on the end surface of the threaded section.

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