A new type of cephalomedullar nail for preventing the posterior tilt of the head and neck bone block

Abstract

The present invention discloses a novel cephalomedullar nail for preventing the backward tilt of head and neck bone blocks, and belongs to the technical field of medical fracture reduction instruments. The cephalomedullar nail with a device for preventing the backward tilt of head and neck bone blocks comprises a main rod, a main nail and an anti-backward tilt screw; the main rod is used to be inserted into the femoral shaft of the patient; the first end of the main nail is penetrated to connect the main rod, and the second end is penetrated to fix the fracture block of the femoral neck and femoral head; the first end of the anti-backward tilt screw is penetrated by the main rod, and the second end is penetrated by the femoral neck medulla, reaching the posterior edge of the anterior cortex of the femoral neck. The problem that the main rod is penetrated by the femoral shaft, and the main nail is penetrated by the femoral neck and femoral head, the cortical alignment is easily lost in the process of obtaining secondary stabilization after postoperative sliding, and the healing rate of the cortical support reduction to the fracture is low is solved. The second end of the anti-backward tilt screw of the present invention is penetrated by the femoral neck medulla, directly reaching the posterior edge of the anterior cortex of the femoral neck, playing a blocking role in preventing the cervical cortex of the head and neck bone block from tilting, falling back, and moving backward.

Description

Technical Field

[0001] The invention relates to the technical field of medical fracture reduction instruments, and in particular to a novel cephalomedullar nail for preventing the backward tilt of head and neck bone blocks. Background Art

[0002] my country is a country with an aging population, especially the number of elderly people over 80 years old is increasing rapidly. In 2013, there were about 700,000 elderly hip fractures in my country, and it is expected to increase to 4 million in 2040. Intertrochanteric fractures account for about half of elderly hip fractures, and most often occur in women. Falls in daily life and osteoporosis are the root causes.

[0003] Currently, closed reduction and cephalo-medullary nail internal fixation are recommended for elderly intertrochanteric fractures. Clinical experience has shown that the quality of fracture reduction is the most important prerequisite for the effect of internal fixation treatment.

[0004] In the prior art, fracture reduction is performed by inserting a main rod into the femoral shaft of the patient, and the main nail is set at an angle. The main nail adopts a tension screw or a spiral blade. The first end of the main nail, that is, the end away from the heart, is inserted and connected to the main rod, and the second end of the main nail, that is, the end close to the heart, is inserted into the femoral neck and femoral head in sequence to fix the fracture fragments of the femoral head and femoral neck. This technology emphasizes the mutual alignment and contact between the head and neck bone fragments and the anterior and medial cortex of the femoral shaft to obtain mutual support after the cortex slides. It is an important guarantee for maintaining the length of the femoral neck, preventing varus deformity, improving fracture stability, reducing the failure rate of treatment, and improving functional effects. It has been widely used clinically at home and abroad.

[0005] However, the positive cortical alignment seen in the anteromedial part of the fracture during surgery may be lost in the process of sliding to obtain secondary stability after surgery, and may develop into a negative alignment, thereby causing excessive sliding and retraction of the head and neck bones. By comparing the cortical alignment between intraoperative fluoroscopy and postoperative 3D-CT images, it was found that a large number of fractures changed after surgery, and only 2 / 3 of the fractures actually achieved cortical support reduction, resulting in a low healing rate of fractures after cortical support reduction. Summary of the invention

[0006] The purpose of the present invention is to provide a new type of cephalomedullar nail to prevent the posterior tilt of the head and neck bone blocks, so as to solve the technical problems existing in the prior art that the main rod is passed through the femoral shaft, and the main nail is passed through the femoral neck and femoral head. In the process of postoperative sliding to obtain secondary stabilization, the cortical alignment is easily lost, and the healing rate of the cortical support reduction to the fracture is low.

[0007] The invention provides a novel cephalomedullar nail for preventing the backward tilt of the head and neck bone block, comprising a main rod, a main nail and an anti-backward tilt screw;

[0008] The main rod is used to be inserted into the patient's femoral shaft;

[0009] The main nail is arranged obliquely, the first end of the main nail is penetrated and connected to the main rod, and the second end of the main nail is penetrated and fixed to the fracture fragments of the femoral neck and femoral head;

[0010] The anti-retroversion screw is tilted, the first end of the anti-retroversion screw passes through the main rod, and the second end of the anti-retroversion screw passes through the femoral neck medullary and reaches the posterior edge of the anterior cortex of the femoral neck.

[0011] Furthermore, a main nail oblique hole is provided on the main rod, and the main nail oblique hole is used for the first end of the main nail to pass through;

[0012] An oblique screw hole is provided on the main rod on the side of the main nail oblique hole in a direction close to the heart, and the oblique screw hole is used for the first end of the anti-retroversion screw to pass through;

[0013] The distance a between the main nail oblique hole and the screw oblique hole ranges from 5 mm to 15 mm.

[0014] Furthermore, the value range of the included angle α between the main nail and the anti-retroversion screw in the vertical direction is between 10° and 30°.

[0015] Furthermore, the number of anti-backward tilt screws is two, and the value range of the included angle α between each anti-backward tilt screw and the main nail in the vertical direction is between 10° and 30°.

[0016] Furthermore, the diameter of the anti-backward tilt screw ranges from 3.5 mm to 5.0 mm, and the length of the anti-backward tilt screw ranges from 35 mm to 55 mm.

[0017] Furthermore, the second end of the anti-retroversion screw is provided with a smooth blunt head, and the smooth blunt head is used to penetrate the femoral cervical spinal cord of the patient.

[0018] Furthermore, a connecting hole is provided at the first end of the anti-retroversion screw, and the connecting hole is used to connect to the extracorporeal guide.

[0019] Further, it also includes a connecting piece;

[0020] The first end of the connecting member is connected to the first end of one of the anti-backward tilt screws, and the second end of the connecting member is connected to the first end of the other anti-backward tilt screw.

[0021] Furthermore, it also includes a support rod arranged obliquely;

[0022] The first end of the strut is connected to the anti-retroversion screw, and the second end of the strut abuts against the outer side of the femoral shaft cortex of the patient.

[0023] Furthermore, there are multiple supporting rods.

[0024] Compared with the prior art, the cephalo-medullary nail with a device for preventing the backward tilt of the head and neck bone block of the present invention has the following advantages:

[0025] The main rod of the present invention is inserted into the femoral shaft of the patient to limit the position of the femoral shaft; the main nail is arranged obliquely so that the first end of the main nail can be penetrated and connected to the main rod, and the connection position of the first end of the main nail is limited; the second end of the main nail penetrates the femoral neck and the femoral head to fix the fracture fragments of the femoral neck and the femoral head; the anti-retroversion screw is arranged obliquely so that the first end of the anti-retroversion screw can be penetrated and connected to the main rod, and the connection position of the first end of the anti-retroversion screw is limited; the second end of the anti-retroversion screw penetrates the femoral neck medullary and directly reaches the posterior edge of the anterior cortex of the femoral neck, plays a blocking role in preventing the neck cortex of the head and neck bone block from tilting, falling back, and moving back, does not affect its sliding to the outside, and the healing rate of the fracture is high due to cortical support reduction. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] 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.

[0027] Figure 1 A schematic diagram of the structure of a first novel cephalomedullar nail for preventing posterior tilt of the head and neck bone block provided by an embodiment of the present invention;

[0028] Figure 2 for Figure 1 A schematic diagram of the structure in direction A;

[0029] Figure 3 for Figure 1 Schematic diagram of the structure in direction B;

[0030] Figure 4 A schematic diagram of the structure of a second cephalomedullar nail with a device for preventing the backward tilt of the head and neck bone block provided in an embodiment of the present invention;

[0031] Figure 5 A schematic structural diagram of a third cephalmedullary nail with a device for preventing posterior tilt of the head and neck bone block provided in an embodiment of the present invention.

[0032] Description of reference numerals:

[0033] 100-main rod; 200-main nail;

[0034] 300-anti-retroversion screw; 400-femoral shaft;

[0035] 500-femoral neck; 600-femoral head;

[0036] 700-connecting piece; 800-support rod;

[0037] 101- oblique hole for main nail; 102- oblique hole for screw;

[0038] 301-smooth blunt head; 302-connecting hole. DETAILED DESCRIPTION

[0039] 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.

[0040] 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 positions or positional relationships based on the positions 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", and the like are only used for descriptive purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, features defined as "first", "second", and the like 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.

[0041] 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 by specific circumstances.

[0042] The present invention will be described in detail below with reference to the accompanying drawings and in conjunction with embodiments.

[0043] like Figures 1 to 3 As shown, a novel cephalomedullar nail for preventing the backward tilt of the head and neck bone block provided by the present invention comprises a main rod 100, a main nail 200 and an anti-backward tilt screw 300;

[0044] The main rod 100 is used to be inserted into the femoral shaft 400 of the patient;

[0045] The main nail 200 is arranged obliquely, the first end of the main nail 200 is penetrated and connected to the main rod 100, and the second end of the main nail 200 is penetrated and fixed to the fracture fragments of the femoral neck 500 and the femoral head 600;

[0046] The anti-retroversion screw 300 is tilted, the first end of the anti-retroversion screw 300 penetrates the main rod 100, and the second end of the anti-retroversion screw 300 penetrates the intramedullary wall of the femoral neck 500 to reach the posterior edge of the anterior cortex of the femoral neck 500.

[0047] In one embodiment of the present invention, Figure 1 As shown, the main rod 100 is vertically arranged, and the main rod 100 is used to be inserted into the femoral shaft 400 of the patient to perform initial positioning of the femoral shaft 400; the main nail 200 is inclined, and the lower end of the main nail 200 is the end away from the heart, and the lower end is connected to the main rod 100 as the first end; the upper end of the main nail 200 is the end close to the heart, and the upper end is connected to the femoral neck 500 and the femoral head 600 as the second end, and is used to fix the fracture fragments of the femoral neck 500 and the femoral head 600. The clamp between the upper end of the main nail 200 and the lower side of the main rod 100 is The angle is 130°; the anti-retroversion screw 300 is tilted, and the lower end of the anti-retroversion screw 300 is the end away from the heart, and the lower end is connected to the main rod 100 as the first end; the upper end of the anti-retroversion screw 300 is the end close to the heart, and the upper end is penetrated into the medullary wall of the femoral neck 500 as the second end, and directly reaches the posterior edge of the anterior cortex of the femoral neck 500, thereby preventing the cervical cortex of the head and neck bone block from tilting, falling back, and moving backward, and will not affect its sliding to the outside, thereby improving the healing rate of cortical support reduction to fracture.

[0048] When in use, the main nail 200 uses a spiral blade, and the coronal plane formed by the spiral blade is arranged parallel to the spiral blade. The vector plane formed by the anti-retroversion screw 300 is inclined forward, that is, inclined in the direction away from the heart.

[0049] Furthermore, the main rod 100 is provided with a main nail oblique hole 101, and the main nail oblique hole 101 is used for the first end of the main nail 200 to pass through;

[0050] On the main rod 100, on the side of the main nail oblique hole 101, close to the heart, a screw oblique hole 102 is provided, and the screw oblique hole 102 is used for the first end of the anti-retroversion screw 300 to pass through;

[0051] The distance a between the main nail oblique hole 101 and the screw oblique hole 102 has a value ranging from 5 mm to 15 mm.

[0052] In one embodiment of the present invention, the main nail oblique hole 101 is an oblique hole formed on the main rod 100, so that the lower end of the main nail 200 can be passed through and fixed in the main nail oblique hole 101; Figure 1As shown, an oblique screw hole 102 is provided above the oblique hole 101 of the main nail, so that the lower end of the anti-retrovert screw 300 can be passed through and fixed in the oblique screw hole 102; the oblique screw hole 102 is provided above the oblique hole 101 of the main nail, so that the anti-retrovert screw 300 can be provided above the main nail 200, so as to facilitate the anti-retrovert screw to pass through the femoral neck 500.

[0053] In this embodiment, the distance a between the main nail oblique hole 101 and the screw oblique hole 102 is set to 10 mm, so that there is a certain installation distance between the main nail 200 and the anti-backward tilt screw 300.

[0054] Furthermore, the value range of the included angle α between the main nail 200 and the anti-backward tilt screw 300 in the vertical direction is between 10° and 30°.

[0055] In one embodiment of the present invention, Figure 2 As shown, the included angle α between the main nail 200 and the anti-retroversion screw 300 in the vertical direction is 15°, so that the vector plane formed by the anti-retroversion screw 300 tilts forward by 15°.

[0056] Furthermore, the number of the anti-backward tilt screws 300 is two, and the value range of the included angle α between each anti-backward tilt screw 300 and the main nail 200 in the vertical direction is between 10° and 30°.

[0057] In one embodiment of the present invention, Figure 2 As shown, the number of anti-backward tilt screws 300 is set to two, and the angle α between each anti-backward tilt screw 300 and the main nail 200 in the vertical direction is 15°. The two anti-backward tilt screws 300 are respectively arranged on the left and right sides of the main nail 200, so that the vector planes formed by the two anti-backward tilt screws 300 are inclined forward by 15°.

[0058] Furthermore, the diameter of the anti-backward tilt screw 300 ranges from 3.5 mm to 5.0 mm, and the length of the anti-backward tilt screw 300 ranges from 35 mm to 55 mm.

[0059] In one embodiment of the present invention, the diameter of the anti-backward tilt screw 300 is 3.5 mm, and the length is 40 mm, so as to ensure that the connection position of the anti-backward tilt screw 300 is accurate.

[0060] In other embodiments, the diameter and length of the anti-backward tilt screw 300 may be other values ​​according to the requirements of use.

[0061] Furthermore, the second end of the anti-retroversion screw 300 is provided with a smooth blunt head 301, and the smooth blunt head 301 is used to penetrate the femoral neck 500 of the patient.

[0062] In one embodiment of the present invention, the upper end of the anti-retroversion screw 300 is a smooth blunt head 301, so that the smooth blunt head 301 can penetrate the femoral neck 500 of the patient.

[0063] In other embodiments of the present invention, a plurality of strip-shaped protrusions may be provided on the outer peripheral surface of the smooth blunt head 301, and the length direction of the strip-shaped protrusions may be provided along the length direction of the smooth blunt head 301, and the cross-section of the strip-shaped protrusions may be conical in shape with a wide inside and a narrow outside, so that when the smooth blunt head 301 is penetrating the femoral neck 500, the sharp ends on the outside of the plurality of strip-shaped protrusions may be used to cut in, thereby facilitating the penetration of the femoral neck 500.

[0064] Furthermore, a connecting hole 302 is provided at the first end of the anti-backward tilt screw 300, and the connecting hole 302 is used to connect to an extracorporeal guide.

[0065] In one embodiment of the present invention, a connection hole 302 is provided at the lower end of the anti-backward tilt screw 300. The connection hole 302 is a hexagonal hole, and the extracorporeal guide uses a hexagonal wrench.

[0066] When in use, the hexagonal wrench is clamped in the connecting hole 302 and the hexagonal wrench is rotated to tighten the anti-retroversion screw 300 into the medullary wall of the femoral neck 500 .

[0067] Furthermore, it also includes a connecting member 700;

[0068] The first end of the connecting member 700 is connected to the first end of one of the anti-backward tilt screws 300 , and the second end of the connecting member 700 is connected to the first end of the other anti-backward tilt screw 300 .

[0069] In one embodiment of the present invention, Figure 4 As shown, the number of the anti-retroversion screws 300 is set to two, and the lower ends of the two anti-retroversion screws 300 are exposed on the outer cortical side of the patient's femoral shaft 400.

[0070] The connecting piece 700 includes a rubber belt in the middle position, and hexagonal plugs are respectively connected to the two ends of the rubber belt. The two hexagonal plugs are respectively blocked in the connecting holes 302 at the lower ends of the two anti-retrovert screws 300. At this time, the rubber belt is in a taut state, and the rubber belt is used to ensure the firmness of the lower end connection position of the two anti-retrovert screws 300. At the same time, the rubber belt has a certain elasticity, which can ensure that the two anti-retrovert screws 300 have a certain tension force, thereby not affecting the patient's daily activities.

[0071] Furthermore, it also includes a support rod 800 disposed obliquely;

[0072] The first end of the support rod 800 is connected to the anti-retroversion screw 300 , and the second end of the support rod 800 abuts against the outer cortical side of the femoral shaft 400 of the patient.

[0073] In one embodiment of the present invention, Figure 5 As shown, the anti-retrotilt screw 300 is set to a relatively long size so that the exposed size of the lower end of the anti-retrotilt screw 300 is relatively long. At this time, a support rod 800 is welded to the side of the lower end of the anti-retrotilt screw 300, and the first end of the support rod 800 is welded to the side of the lower end of the anti-retrotilt screw 300, and the second end of the support rod 800 directly abuts against the outer cortical position of the patient's femoral shaft 400.

[0074] There is a certain angle between the support rod 800 and the anti-retrovert screw 300, for example, a 45° angle, so that the second end of the support rod 800 can directly abut against the outer cortical position of the patient's femoral shaft 400, and the support rod 800 is used to support and limit the lower end position of the anti-retrovert screw 300.

[0075] Furthermore, there are multiple support rods 800.

[0076] In one embodiment of the present invention, a plurality of support rods 800 are welded to the lower side of the anti-backward tilt screw 300 so as to support and limit the lower side position of the anti-backward tilt screw 300 from multiple directions using the plurality of support rods 800.

[0077] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A new type of cephalomedullar nail for preventing the backward tilt of the head and neck bone block, characterized in that: It comprises a main rod (100), a main nail (200) and an anti-backward tilt screw (300); The main rod (100) is used to be inserted into the femoral shaft (400) of a patient; The main nail (200) is arranged obliquely, the first end of the main nail (200) is penetrated and connected to the main rod (100), and the second end of the main nail (200) is penetrated and fixed to the fracture fragments of the femoral neck (500) and the femoral head (600); The anti-retroversion screw (300) is arranged obliquely, the first end of the anti-retroversion screw (300) passes through the main rod (100), and the second end of the anti-retroversion screw (300) passes through the intramedullary tissue of the femoral neck (500) to reach the posterior edge of the anterior cortex of the femoral neck (500); The main rod (100) is provided with a main nail oblique hole (101), and the main nail oblique hole (101) is used for the first end of the main nail (200) to pass through; An oblique screw hole (102) is provided on the main rod (100) on the side of the main nail oblique hole (101) in a direction close to the heart, and the oblique screw hole (102) is used for the first end of the anti-retroversion screw (300) to pass through; The distance a between the main nail oblique hole (101) and the screw oblique hole (102) has a value ranging from 5 mm to 15 mm; The number of the anti-backward tilt screws (300) is two, and the value range of the included angle α between each anti-backward tilt screw (300) and the main nail (200) in the vertical direction is between 10° and 30°.

2. The novel cephalomedullar nail for preventing posterior tilt of the head and neck bone block according to claim 1 is characterized in that: The diameter of the anti-backward tilt screw (300) is in the range of 3.5 mm to 5.0 mm, and the length of the anti-backward tilt screw (300) is in the range of 35 mm to 55 mm.

3. The novel cephalomedullar nail for preventing posterior tilt of head and neck bone blocks according to claim 1 is characterized in that: The second end of the anti-retroversion screw (300) is provided with a smooth blunt head (301), and the smooth blunt head (301) is used to penetrate the medullary wall of the femoral neck (500) of the patient.

4. The novel cephalomedullar nail for preventing posterior tilt of head and neck bone blocks according to claim 1 is characterized in that: The first end of the anti-backward tilt screw (300) is provided with a connection hole (302), and the connection hole (302) is used to connect to an extracorporeal guide.

5. The novel cephalomedullar nail for preventing posterior tilt of head and neck bone block according to claim 1 is characterized in that: Also includes a connecting piece (700); The first end of the connecting member (700) is connected to the first end of one of the anti-backward tilt screws (300), and the second end of the connecting member (700) is connected to the first end of another anti-backward tilt screw (300).

6. The novel cephalomedullar nail for preventing posterior tilt of head and neck bone block according to claim 1, characterized in that: Also included is a support rod (800) arranged obliquely; The first end of the support rod (800) is connected to the anti-retroversion screw (300), and the second end of the support rod (800) abuts against the outer cortical side of the femoral shaft (400) of the patient.

7. The novel cephalomedullar nail for preventing posterior tilt of head and neck bone block according to claim 6 is characterized in that: The number of the support rods (800) is plural.

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