An internal fixation system for intertrochanteric fracture

Abstract

The present invention provides an intertrochanteric fracture internal fixation system, comprising a plate having a proximal end and a distal end, with the proximal end wrapping around the greater trochanter, forming a three-dimensional structure. This intertrochanteric fracture internal fixation system can fix both coronal and sagittal plane fractures, achieving three-dimensional fixation of the intertrochanteric fracture. It is suitable for fixation of fractures that include both axial intertrochanteric fractures and anterior-posterior separation. Furthermore, this internal fixation system facilitates fixation of small fracture fragments within the fracture site.

Description

Technical Field

[0001] The present invention belongs to the technical field of medical devices, and in particular relates to an internal fixation system for intertrochanteric fractures of the femur. Background Art

[0002] Intertrochanteric fractures, also known as intertrochanteric fractures, are extracapsular fractures. Current treatments for intertrochanteric fractures often utilize a dynamic hip screw system. This dynamic hip system comprises a sleeve plate, a lag screw, and a compression screw. The specific procedure is as follows: After inserting the lag screw until it reaches the appropriate length, the sleeve plate is inserted; after the sleeve plate is inserted, a compression screw is screwed in to secure the sleeve plate. For intertrochanteric fractures, the lag screw is confined within the sleeve of the sleeve plate. The fit between the sleeve plate and the lag screw is too rigid, reducing the movement of the fracture ends, resulting in no movement under physiological loads. The dynamic hip screw system can further damage the fracture area, leading to bone loss and anterior-posterior separation of the fracture, resulting in poor stabilization. Furthermore, the lack of a gap between the compression screw and the sleeve plate prevents compression between the fracture fragments, hindering fracture healing. Furthermore, the system is unable to fix the fractured bones when the femoral head is fragmented. Summary of the Invention

[0003] To solve the above technical problems, the present invention provides an internal fixation system for intertrochanteric fractures of the femur. The internal fixation system for intertrochanteric fractures of the femur can achieve fixation of both coronal plane fractures and sagittal plane fractures, thereby achieving three-dimensional fixation of the intertrochanteric fracture of the femur. The system is suitable for fixation of not only longitudinal intertrochanteric fractures but also fractures with anterior-posterior separation. In addition, the internal fixation system is conducive to fixing small fracture fragments at the fracture site.

[0004] In order to achieve the above object, the present invention provides the following technical solutions:

[0005] A femoral intertrochanteric fracture internal fixation system comprises a bone plate. The bone plate comprises a proximal end and a distal end. The proximal end wraps around the greater trochanter to form a three-dimensional structure.

[0006] Furthermore, the proximal end covers more than 30% of the surface area of ​​the greater trochanter.

[0007] Furthermore, a plurality of first fixing holes are provided at the proximal end, and axes of the plurality of first fixing holes are not completely parallel.

[0008] Preferably, the plurality of first fixing holes are distributed on both sides of the bone fracture.

[0009] Preferably, the distal end is provided with a fourth fixing hole.

[0010] Furthermore, a third fixing hole is provided at the connection between the proximal end and the distal end.

[0011] Preferably, at least two second fixing holes are further provided at a position of the proximal end close to the distal end, and the at least two second fixing holes and the third fixing hole are distributed in a triangular shape;

[0012] Preferably, the first fixing hole and the second fixing hole are both ball-and-socket holes.

[0013] Furthermore, the intertrochanteric fracture internal fixation system further comprises a lag screw; the lag screw is implanted into the bone through the third fixation hole.

[0014] Furthermore, the intertrochanteric fracture internal fixation system also includes a nut, which includes a head and a rod. The head is larger than the aperture of the third fixation hole, and the rod is threadedly connected to one end of the tension screw.

[0015] Furthermore, the tension screw includes a first section, a second section and a third section connected in sequence; the rod portion is a hollow structure, and a thread is provided in the hollow structure; the hollow structure is threadedly connected to the first section.

[0016] Furthermore, the rod portion is provided with a plurality of axial notches.

[0017] Preferably, an anti-retraction boss is circumferentially provided at one end of the rod away from the head.

[0018] Furthermore, the third fixing hole is a smooth hole, and there is a gap between the rod and the third fixing hole.

[0019] Furthermore, the intertrochanteric fracture internal fixation system further includes a first screw disposed in the first fixation hole; a second screw disposed in the second fixation hole; and a fourth screw disposed in the fourth fixation hole.

[0020] Compared with the prior art, the present invention has the following beneficial effects:

[0021] The intertrochanteric fracture internal fixation system provided by the present invention provides a certain degree of coverage for the fixation of the greater trochanteric region, and can achieve fixation of both coronal and sagittal plane fractures, thereby achieving three-dimensional fixation. The internal fixation system is applicable to fixation of not only intertrochanteric fractures but also fractures with anterior-posterior separation.

[0022] The intertrochanteric fracture internal fixation system provided by the present invention can wrap around small fracture fragments and provide temporary support for the fixation of small fracture fragments.

[0023] The femoral intertrochanteric fracture internal fixation system provided by the present invention has multiple first fixation holes provided at its proximal end, which can fix small fracture fragments and achieve mechanical dispersion, so that the internal fixation system has no stress concentration. The multiple first fixation holes are distributed on both sides of the fracture suture, which is conducive to the closure of the fracture suture.

[0024] In the intertrochanteric fracture internal fixation system provided by the present invention, the second fixation hole and the third fixation hole provided at the proximal end are distributed in a triangular shape, which helps to stabilize the bone plate and disperse stress;

[0025] The intertrochanteric fracture internal fixation system provided by the present invention has a structure in which, when the nut is tightened, the nut is squeezed against the bone plate (the bone plate serves as a resistance plate), and the tension screw is withdrawn, thereby applying pressure to the fracture ends and facilitating closure of the fracture suture. Furthermore, a gap exists between the nut and the third fixing hole of the bone plate, and a portion of the neck-shaft angle is lost during use. This relatively stable fixation technique is conducive to promoting callus formation and fracture healing.

[0026] The intertrochanteric fracture internal fixation system provided by the present invention can reduce the damage of local tissues, create a good environment for fracture repair, and promote bone healing. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 This is a schematic structural diagram of the intertrochanteric fracture internal fixation system provided by one embodiment of the present invention when in use;

[0028] Figure 2 1 is a schematic diagram of the three-dimensional structure of an intertrochanteric fracture internal fixation system provided by one embodiment of the present invention;

[0029] Figure 3 is a schematic structural diagram from another angle of the intertrochanteric fracture internal fixation system provided by one embodiment of the present invention;

[0030] Figure 4 This is a schematic structural diagram of a tension screw provided by one embodiment of the present invention;

[0031] Figure 5 1 is a schematic structural diagram of a nut provided in one embodiment of the present invention;

[0032] Figure 6 It is a cross-sectional view of a nut provided in one embodiment of the present invention.

[0033] in:

[0034] 1. Bone plate;

[0035] 11, proximal end; 111, first fixing hole; 112, second fixing hole;

[0036] 12. distal end; 121. fourth fixing hole;

[0037] 13. The third fixing hole;

[0038] 2. Lag screw; 21. First section; 22. Second section; 23. Third section;

[0039] 3. Nut; 31. Head; 32. Stem; 33. Notch; 34. Anti-retraction boss; 35. Internal thread;

[0040] 4. First screw;

[0041] 5. Second screw;

[0042] 6. Large rotor;

[0043] 7. Femoral head;

[0044] 8. Femoral neck. DETAILED DESCRIPTION

[0045] It should be noted that, in the absence of conflict, the embodiments of the present invention and the features in the embodiments may be combined with each other.

[0046] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying 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", etc. are only used for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, features defined as "first", "second", etc. may explicitly or implicitly include one or more of the features. In the description of the present invention, unless otherwise specified, "multiple" means two or more.

[0047] In the description of the present invention, it should be noted that, unless otherwise expressly specified or limited, the terms "mounted," "connected," and "connected" should be understood in a broad sense. For example, they may refer to fixed connections, detachable connections, or integral connections; mechanical connections or electrical connections; direct connections or indirect connections through an intermediate medium; and internal communication between two components. Those skilled in the art will understand the specific meanings of the above terms in the present invention based on specific circumstances.

[0048] For intertrochanteric fractures, especially fixation problems caused by femoral head fragmentation, the present invention provides an intertrochanteric fracture internal fixation system that can solve fractures that include not only axial intertrochanteric fractures but also anterior-posterior separation. Good fixation requires both a good fixation method or material and mechanical dispersion as much as possible, rather than mechanical concentration. Simultaneously, in terms of the fixation method, local tissue damage should be minimized to create a good environment for fracture repair, thereby promoting bone healing. The intertrochanteric fracture internal fixation system of the present invention can relatively effectively solve the above problems.

[0049] The intertrochanteric fracture internal fixation system provided by the present invention comprises a bone plate. The bone plate comprises a proximal end and a distal end. The proximal end wraps around the greater trochanter to form a three-dimensional structure.

[0050] Intertrochanteric fractures are a common type of fracture, and the femoral head often breaks. Designing the proximal end of the plate into a wrapping shape can wrap the small fracture fragments. Using small screws to fix the small fracture fragments can provide temporary support, overcoming the problem of difficult fixation of small fracture fragments in existing technologies.

[0051] In addition, for intertrochanteric fractures, the fixation of the greater trochanter area has a certain degree of coverage, which can solve the fixation of both coronal and sagittal plane fractures, achieving a three-dimensional fixation method. This fixation method can solve fractures with not only longitudinal intertrochanteric fractures but also anterior-posterior separation fractures.

[0052] In addition, wrapping the greater trochanter at the proximal end of the plate can achieve mechanical dispersion as much as possible without stress concentration, minimize local tissue damage, create a good environment for fracture repair, and promote fracture healing.

[0053] Furthermore, the proximal end preferably encompasses more than 30% of the surface area of ​​the greater trochanter, such as 35%, 45%, 55%, 60%, 70%, or 80% of the surface area of ​​the greater trochanter. In this case, the proximal end of the plate can fully encompass the greater trochanter, achieving its intended purpose. The specific shape of the proximal end of the plate can be varied, such as a palm-shaped proximal end with multiple protrusions designed on the end distal to the distal end; the proximal end can also be spherical, etc. Those skilled in the art can design the desired proximal end of the plate based on the location of the fracture, bone characteristics, and stress distribution. Preferably, the proximal end of the plate is palm-shaped, with multiple protrusions designed on the end distal to the distal end.

[0054] Furthermore, a plurality of first fixing holes are provided at the proximal end, and the axes of the plurality of first fixing holes are not completely parallel, so that the first screws provided in the first fixing holes form a cross-locking on the fracture site after implantation, which helps to prevent the plate from being withdrawn, improves the fixation effect of the intertrochanteric fracture internal fixation system, and also helps to fix small fracture fragments.

[0055] The distribution of the first fixation holes at the proximal end can take into account the distribution of small fracture fragments, the location of the fracture, bone characteristics, and stress distribution characteristics. Those skilled in the art can design the holes based on actual needs. Preferably, the first fixation holes are located at the proximal end of the plate, distal from the distal end, and are preferably two or more, such as three, four, five, or six, depending on the size of the proximal end of the plate. The centers of the multiple first fixation holes are not aligned. Preferably, there are three first fixation holes, and the line connecting the centers of the three first fixation holes forms a triangle.

[0056] Preferably, the plurality of first fixing holes are distributed on both sides of the fracture seam, and the first screws are located on both sides of the fracture seam after implantation, which helps to close the fracture seam.

[0057] Preferably, the distal end is provided with a fourth fixing hole for fixing the distal end of the bone plate. The fourth fixing hole can be a composite hole, a common threaded hole or a universal hole, etc. Different hole shapes match different types of fourth screws.

[0058] Furthermore, a third fixing hole is provided at the connection between the proximal end and the distal end, and the third fixing hole is used to place a lag screw. For fractures, the lag screw plays a supporting role.

[0059] Preferably, at least two second fixation holes are provided near the distal end of the proximal end, and the at least two second fixation holes and the third fixation hole are preferably arranged in a triangular pattern. This allows the second screws and the lag screws provided in the second fixation holes to provide tension protection, firmly fix the fracture site, and maintain the neck-shaft angle. Preferably, the axes of the at least two second fixation holes are angled to enhance locking and contribute to bone plate stability. Furthermore, the arrangement of the second fixation holes can disperse stress.

[0060] Preferably, the first fixing hole and the second fixing hole are both ball-and-socket holes, which facilitates the doctor to select a suitable angle to fix the small bone fragment during surgery.

[0061] Furthermore, the intertrochanteric fracture internal fixation system further comprises a lag screw; the lag screw is implanted into the bone through the third fixation hole to play a supporting role.

[0062] The tension screw can be an ordinary tension screw, which includes a head and a rod. The size of the head can be larger than the size of the third fixing hole to ensure the fixation between the tension screw and the bone plate; a section of the rod away from the head is provided with an external thread, and a section close to the head is a plain rod to exert pressure on the fracture.

[0063] Preferably, the tension screw comprises a first section, a second section and a third section connected in sequence, the first section can cooperate with the nut to achieve a secondary pressure locking effect; the second section and the third section are implanted in the bone, and preferably the thread progression of the first section and the third section is the same.

[0064] The nut includes a head and a rod. The head is larger than the aperture of the third fixing hole, and the rod is threadedly connected to one end of the tension screw.

[0065] The threaded connection between the nut shank and the first section of the tension screw can take various forms, such as a hollow structure with internal threads, an external thread on the nut shank, and a threaded connection between the hollow structure and the shank; or a hollow structure with external threads, a hollow structure with internal threads, and a threaded connection between the external threads and the internal threads in the hollow structure. The connection between the nut shank and the first section of the tension screw can also take other forms, as long as the connection can provide secondary pressure and secure the tension screw. Preferably, the shank is a hollow structure with threads, and the hollow structure is threadedly connected to the first section.

[0066] The femoral trochanteric fracture internal fixation system provided by the present invention uses a tension screw and a nut in combination. Its advantage is that when the nut is tightened, the nut is squeezed against the bone plate (the bone plate is a resistance plate), and the tension screw is pulled out to apply pressure to the fracture ends, which is conducive to the closure of the fracture seam.

[0067] Furthermore, in order to facilitate the smooth insertion of the nut rod into the third fixing hole, the rod is provided with multiple axial notches, that is, the nut rod is an elastic thin structure, and the rod has a certain elasticity, which facilitates its pressing into the bone plate and connecting with the tension screw.

[0068] Furthermore, in order to prevent the nut stem from withdrawing from the third fixing hole after being connected to the tension screw, an anti-withdrawal boss is circumferentially provided at one end of the nut stem away from the head. The design of the anti-withdrawal boss also improves the reliability of the product.

[0069] Furthermore, the third fixing hole is a smooth hole, and there is a gap between the rod and the third fixing hole. Too rigid a lock can cause nail breakage. Additionally, when a trochanteric fracture internal fixation system is too rigid, a low-strain environment is created, resulting in nonunion or delayed healing of the fracture. During use, the trochanteric fracture internal fixation system of the present invention has a gap between the nut and the plate, and the neck-shaft angle loses 5° to 10°. This relatively stable fixation technique promotes callus formation and facilitates fracture healing.

[0070] Furthermore, the intertrochanteric fracture internal fixation system further includes a first screw disposed in the first fixation hole; a second screw disposed in the second fixation hole; and a fourth screw disposed in the fourth fixation hole.

[0071] The method of using the femoral trochanteric fracture internal fixation system is as follows:

[0072] The plate is implanted in the appropriate position. A combination reamer is then used to drill a base hole, followed by tapping with a lag tap. Finally, a lag screw is inserted to secure the larger bone fragment. After the lag screw is passed through the fracture line, the nut at the end of the screw is tightened. This compresses the plate (the plate acts as a resistance plate), allowing the screw to be withdrawn. The head of the lag screw applies tension and pressure to the fracture surface. Once the pressure reaches a certain level, the nut at the end locks the lag screw. Finally, the first, second, and fourth screws are inserted to complete the fixation of the femoral trochanteric fracture. There is no specific order for the placement of the first, second, and fourth screws; the operator can select the order of placement based on their needs.

[0073] The present invention will be described in detail below with reference to the accompanying drawings and in conjunction with embodiments.

[0074] like Figure 1-6 As shown, a femoral intertrochanteric fracture internal fixation system includes a bone plate 1, a first screw 4, a second screw 5, a lag screw 2, a fourth screw and a nut 3.

[0075] The bone plate 1 includes a proximal end 11 and a distal end 12; the proximal end 11 is palm-shaped, wrapping the greater trochanter 6 and forming a three-dimensional structure; preferably, the proximal end 11 wraps more than 50% of the surface area of ​​the greater trochanter 6, such as 55%, 60%, 70% or 80% of the surface area of ​​the greater trochanter 6.

[0076] Three first fixing holes 111 are provided at one end of the proximal end 11 of the bone plate 1 away from the distal end 12 . The axes of the three first fixing holes 111 are not completely parallel, so that the first screws 4 located in the first fixing holes 111 are in a cross-locking state after implantation.

[0077] Two second fixing holes 112 are provided at one end of the proximal end 11 close to the distal end 12 , and second screws 5 are provided in the second fixing holes 112 .

[0078] A third fixing hole 13 is provided at the connection between the proximal end 11 and the distal end 12 , and the third fixing hole 13 is a light hole.

[0079] The distal end 12 is provided with a fourth fixing hole 121 , in which a fourth screw is provided. In this embodiment, there are three fourth fixing holes 121 , all of which are composite holes, and the fourth screw can cooperate with the composite hole.

[0080] The tension screw 2 includes a first section 21, a second section 22 and a third section 23 connected in sequence. The first section 21 and the third section 23 are both threaded sections with the same thread progression; the second section 22 is a polished rod section.

[0081] The nut 3 includes a head 31 and a stem 32. The stem 32 is a hollow structure with an internal thread 35. The stem 32 is provided with a plurality of axial notches 33 along its axis. That is, the stem 32 of the nut 3 is an elastic and thin structure. The stem 32 has a certain elasticity, which facilitates its pressing into the bone plate 1 and connection with the tension screw 2. An anti-retraction boss 34 is circumferentially provided on the end of the stem 32 of the nut 3 away from the head 31.

[0082] The tension screw 2 is implanted into the bone through the third fixing hole 13 , and the rod portion 32 of the nut 3 is threadedly connected to the first section 21 , with a certain gap between the rod portion 32 and the third fixing hole 13 after the connection.

[0083] The method of using the femoral trochanteric fracture internal fixation system is as follows:

[0084] After implanting the plate 1 in the appropriate position, a combination reamer is used to create a base hole, followed by tapping with a lag tap. Finally, a lag screw 2 is inserted to secure the larger bone fragment. After the lag screw 2 is passed through the fracture line, the nut 3 at the end of the screw 2 is tightened. This compresses the plate 1 (the plate 1 acts as a resistance plate), allowing the screw 2 to be withdrawn. The head 31 of the lag screw 2 applies tension and pressure to the fracture surface. Once the pressure reaches a certain level, the nut 3 at the end of the screw locks the lag screw 2. Finally, the first, second, and fourth screws are inserted to complete the fixation of the trochanteric fracture. There is no specific order for the placement of the first, second, and fourth screws; the operator can select the order of placement based on their needs.

[0085] In summary, the intertrochanteric fracture internal fixation system provided by the present invention provides a certain degree of envelopment for fixation of the greater trochanteric region, and can achieve fixation of both coronal and sagittal plane fractures, thereby achieving three-dimensional fixation. The internal fixation system is applicable to fixation of not only intertrochanteric fractures but also fractures with anterior-posterior separation. The system can also envelop small fracture fragments, providing temporary support for their fixation.

[0086] The multiple first fixation holes provided at the proximal end of the bone plate can fix small fracture fragments and achieve mechanical dispersion, so that the internal fixation system has no stress concentration; the multiple first fixation holes are distributed on both sides of the fracture seam, which is conducive to the closure of the fracture seam;

[0087] The second fixing hole and the third fixing hole provided at the proximal end of the bone plate are distributed in a triangular pattern, which helps to stabilize the bone plate and disperse stress;

[0088] This intertrochanteric fracture internal fixation system uses a screw that squeezes the bone plate (the plate acts as a resistance plate) when the nut is tightened, allowing the tension screw to be withdrawn, applying pressure to the fracture ends and facilitating fracture closure. Furthermore, a gap exists between the nut and the third fixation hole of the plate, which partially reduces the neck-shaft angle during use. This relatively stable fixation technique promotes callus formation and facilitates fracture healing.

[0089] In addition, the intertrochanteric fracture internal fixation system can reduce local tissue damage, create a good environment for fracture repair, and promote bone healing.

[0090] The above is a detailed description of an embodiment of the present invention. However, the content described is only a preferred embodiment of the present invention and should not be considered to limit the scope of the present invention. All equivalent changes and improvements made within the scope of the present invention should still fall within the scope of the patent coverage of the present invention.

Claims

1. A femoral intertrochanteric fracture internal fixation system, characterized by: The bone plate comprises a proximal end and a distal end, wherein the proximal end wraps around the greater trochanter and presents a three-dimensional structure; A third fixing hole is provided at the connection between the proximal end and the distal end; The intertrochanteric fracture internal fixation system further comprises a lag screw; the lag screw is implanted into the bone through the third fixation hole; The intertrochanteric fracture internal fixation system further comprises a nut, which comprises a head and a stem, wherein the head is larger than the diameter of the third fixing hole, and the stem is threadedly connected to one end of the lag screw; The rod is provided with a plurality of axial notches; an anti-retraction boss is circumferentially provided at one end of the rod away from the head; The third fixing hole is a smooth hole, and there is a gap between the rod and the third fixing hole; The tension screw comprises a first section, a second section and a third section which are connected in sequence; the rod portion is a hollow structure, and a thread is provided in the hollow structure; the hollow structure is threadedly connected to the first section.

2. The intertrochanteric fracture internal fixation system according to claim 1, characterized in that: The proximal end covers more than 30% of the surface area of ​​the greater trochanter.

3. The intertrochanteric fracture internal fixation system according to claim 1 or 2, characterized in that: The proximal end is provided with a plurality of first fixing holes, and the axes of the plurality of first fixing holes are not completely parallel; The plurality of first fixing holes are distributed on both sides of the bone fracture; The distal end is provided with a fourth fixing hole.

4. The intertrochanteric fracture internal fixation system according to claim 3, characterized in that: At least two second fixing holes are further provided at a position of the proximal end close to the distal end, and the at least two second fixing holes and the third fixing hole are distributed in a triangular shape; The first fixing hole and the second fixing hole are both ball and socket holes.

5. The intertrochanteric fracture internal fixation system according to claim 4, characterized in that: The intertrochanteric fracture internal fixation system further includes a first screw arranged in the first fixation hole; a second screw arranged in the second fixation hole; and a fourth screw arranged in the fourth fixation hole.

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