CN219021477U - Internal fixing device for femoral neck fracture - Google Patents

Abstract

The utility model belongs to the technical field of medical machinery, and provides an internal fixing device for femoral neck fracture. A sleeve is arranged on the inner side of the lower end of the steel plate, and a locking pressurizing screw hole is arranged above the sleeve on the steel plate; the sleeve is internally provided with threads which are matched with the tail cap, and the main nails can be limited to withdraw after locking; a sleeve flange is arranged in the tail end of the sleeve, a main nail flange is arranged on the main nail, and the main nail flange is matched with the sleeve flange to limit the main nail to penetrate out of the sleeve; the main nail is provided with an anti-rotation nail hole, the transverse nail is matched with the anti-rotation nail hole, and the central axis of the transverse nail is mutually perpendicular to the central axis of the main nail in all directions; the head of the main nail is a conical nail head, and three blade lobes are arranged on the conical nail head along the length direction of the main nail, so as to support the femoral head and prevent the femoral head from rotating. The fixing device can realize limited sliding pressurization of the fracture end, simultaneously prevent unstable rotation of the fracture end of the femoral head and prevent the main nail from cutting out the femoral head, and has better clinical effect.

Description

Internal fixing device for femoral neck fracture

Technical Field

The utility model relates to the technical field of medical machinery, in particular to an internal fixing device for femoral neck fracture.

Background

Femoral neck fracture is one of the common hip fracture in clinic, and the old patients are mostly osteoporosis fracture and the young and the old are mostly unstable fracture caused by high-energy injury. According to anatomical positions, femur neck fractures can be divided into under-head, middle-neck and basal type; according to Pauwell's angle, the angle can be divided into I type (less than 30 degrees), II type (30-50 degrees) and III type (more than 50 degrees), the shearing force of the fracture end of the bone increases along with the increase of the angle, the failure rate of internal fixation treatment also increases, and the internal fixation is often withdrawn or penetrated out of the femoral head, thus becoming a clinical treatment problem.

For the patients with fracture of the femoral neck under 65 years old, partial fracture of the femoral neck with good bone quality and high activity, the most common method at present is still internal fixation operation. Because of the high failure rate of internal fixation treatment in elderly femoral neck fracture patients, orthopedics may choose a hip arthroplasty but may be at a high risk of later revision. The most important thing of the internal fixation of the fracture of the femoral neck is good reduction and strong fixation, so that the fracture healing environment can be provided. The fracture healing is obviously affected by the biomechanical characteristics of the internal fixing device besides the characteristics of fracture per se among the factors causing the treatment failure because of higher failure rate of the femoral neck fracture treatment. Currently, many internal fixation devices are used, including cannulated screws, dynamic hip screws (dynamic hip screw, DHS), dynamic condyle screws (dynamic condylar screw, DCS), femoral neck internal fixation systems (femoral neck system, FNS), proximal femoral plate (proximal femoral locking plate, PFLP), percutaneous compression plate (percutaneous compression plate, PCCP), medial buttress plate, and intramedullary fixation systems. The internal fixing device for the femoral neck fracture, which is clinically applied at present, can well pressurize a fracture end, but in the loading process, excessive sliding pressurization often causes complications such as withdrawal of an internal fixture, penetration of a femoral head, fracture and the like, and causes complications such as femoral head necrosis, fracture disunion, excessive shortening of a femoral neck, hip dysfunction and the like.

The utility model patent with publication number CN 209808502U discloses a novel internal fixing device for femoral neck fracture, which comprises a tuberosity main nail and a plurality of lag screws, wherein 3-4 main nail holes are formed in the nail body of the tuberosity main nail, 3-4 lag screws are arranged on the nail body of the tuberosity main nail, the tuberosity main nail is obliquely and internally driven into the upper part of a small tuberosity from the outer side of a femur tuberosity, and at least 3 lag screws are driven into a femoral head from the proximal end of the femur through a femoral neck and pass through the main nail holes in the tuberosity main nail. The utility model enhances the compression resistance and rotation resistance of internal fixation, but the device does not limit the axial movement of the main nail, and has higher risk of withdrawing the nail and penetrating the screw out of the femoral head.

Therefore, the existing internal fixation mode of femoral neck fracture has the defect that the femoral head fracture end cannot form a locking relation with internal fixation, the device improves the existing mode, designs a limited pressurizing internal fixation device with the vertical cross locking of the femoral head fracture end, prevents the risk of the internal fixation device from withdrawing or penetrating out of the femoral head in the loading process, reduces the incidence rate of fracture disunion and femoral head necrosis, and has important clinical value.

Disclosure of Invention

In order to solve the above problems, an object of the present utility model is to provide an internal fixation device for fracture of a femoral neck, which can compress the fracture end in a limited manner while effectively preventing rotational instability of the fracture end of the femoral head and preventing the main nail from cutting out the femoral head, thereby having a better clinical effect and preventing fracture nonunion and femoral head necrosis.

In order to achieve the above purpose, the technical scheme adopted by the utility model is as follows:

an internal fixing device for femoral neck fracture comprises a steel plate, a sleeve, a main nail, a cross nail and a tail cap; the inner side surface of the steel plate is matched with the anatomical form of the proximal outer side wall of the femur, when the inner side surface of the steel plate is attached to the anatomical form of the proximal outer side wall of the femur, the surfaces which define the front side and the rear side of the hip of a human body of the steel plate are respectively the front side surface of the steel plate and the rear side surface of the steel plate, the inner side of the lower end of the steel plate is provided with a sleeve which is used for inserting femur moment and allowing a main nail to axially pass through, the steel plate is provided with a main nail hole, the sleeve is connected at the main nail hole, the inner side of one end of the sleeve, far from the steel plate, is circumferentially provided with a sleeve flange, the inner wall of the sleeve, close to the steel plate, is provided with threads, and the tail cap can be connected with the sleeve through threads after being inserted into the sleeve from the main nail hole; the lateral surface of the main nail is provided with more than one anti-rotation nail hole from the head part of the main nail to the middle part of the main nail, and the transverse nail is used for being connected with the anti-rotation nail hole in a matching way; the outer side wall of the tail end of the main nail is circumferentially provided with a main nail flange with the length of 10-15mm, and the main nail flange is matched with the sleeve flange to prevent the main nail from slipping from the sleeve when sliding; and an anti-rotation structure for preventing the circumferential rotation of the main nail is further arranged between the outer wall of the main nail and the inner wall of the sleeve, and when the main nail is sleeved into the sleeve and is connected through the anti-rotation structure, the extending direction of the central axis of the anti-rotation nail hole is consistent with the front-back direction between the front side surface of the steel plate and the back side surface of the steel plate.

In the utility model, preferably, the anti-rotation structure is a groove and a rib which are matched with each other, namely, the outer wall of the main nail is provided with the rib along the axial direction, the inner wall of the sleeve is provided with the groove along the axial direction, or the outer wall of the main nail is provided with the groove along the axial direction, the inner wall of the sleeve is provided with the rib along the axial direction, and the rib is connected in the groove in a sliding way to prevent the circumferential rotation of the main nail; when the inner wall of the sleeve is provided with a convex rib along the axial direction, the flange of the main nail is also provided with a notch matched with the convex rib; the grooves or the ribs are arranged in the sleeve at positions which are far away from the steel plate as far as possible, and the length of the grooves or the ribs is 8-12cm; when the main nail is in sliding connection in the sleeve through the groove and the convex rib structure, the extending direction of the central axis of the anti-rotation nail hole is consistent with the front and back directions of the front side surface and the back side surface of the steel plate.

In the utility model, preferably, the number of the anti-rotation nail holes is three, the three anti-rotation nail holes are arranged at intervals along the axial direction of the main nail, and the central axis of the anti-rotation nail hole is mutually perpendicular to the central axis of the main nail.

In the utility model, preferably, the head of the main nail is a conical nail head, three blade lobes are arranged on the conical nail head along the length direction of the main nail, each blade lobe is arranged along the circumferential direction of the conical nail head, and a blade groove is arranged between two adjacent blade lobes.

In the utility model, preferably, the main nail is provided with a hollow channel along the central axis, and the hollow channel penetrates through the whole main nail and can be used for passing a Kirschner wire with the diameter of 2.5 mm.

In the present utility model, preferably, a locking pressing nail hole is provided above the sleeve on the steel plate, and a locking screw or a normal screw is provided in the locking pressing nail hole.

In the present utility model, it is preferable that the sleeve is disposed obliquely inside the steel plate, and an angle between the sleeve and the steel plate is 120 °.

In the present utility model, preferably, the sleeve has a length of 30-40mm.

In the present utility model, preferably, the steel plate is provided with 2.0mm k-wire nail holes.

In the utility model, preferably, the locking pressurizing nail hole comprises a hole I and a hole II which are communicated with each other, the inner diameters of the hole I and the hole II are the same, the hole I is far away from the main nail hole, the inner wall of the hole I is provided with an internal thread for connecting a locking screw, the hole II is close to the main nail hole, and the inner wall of the hole II is a smooth surface for connecting a common screw.

By adopting the technical scheme, the utility model has the following beneficial effects:

1. the transverse nails are perpendicular to the main nails, the main nails are driven from front to back when the bone fracture fixator is used, the transverse nails are perpendicular to trabecular travel, the bone fracture fixator has stronger and stable biomechanical characteristics, the conical blade structure of the main nails retains more bone mass, the bearing area of the blade groove surface is increased, and the rotation of the femoral head and the penetration of the internal fixing device out of the femoral head can be well prevented.

2. When the utility model is used, the proper tail cap is selected, so that a gap is reserved between the tail cap and the main nail, static locking or limited pressurization of a fracture end can be met, and the main nail is ensured not to excessively axially slide to withdraw the nail when in use, thereby ensuring the clinical treatment effect and preventing complications such as fracture nonunion, femoral head necrosis and the like.

3. According to the utility model, three anti-rotation nail holes are arranged on the main nail at intervals, so that the requirements of fixing three types of fracture such as under-head type fracture, neck type fracture and basal type fracture can be met, and the three fracture positions can be adaptively matched.

4. The utility model also provides a steel plate nail hole as a locking pressurizing nail hole, and can be fixed by using a locking screw or a common screw according to the fracture clearance condition, and can be flexibly selected according to specific fracture and reduction conditions.

Drawings

FIG. 1 is a functional schematic of the internal fixation device for femoral neck fractures of the present utility model;

FIG. 2 is a longitudinal section of the utility model showing the attachment of the main pin to the sleeve;

FIG. 3 is a view of the present utility model from the main head of the main pin in a connected condition with the sleeve;

FIG. 4 is a schematic view of the structure of the steel plate and sleeve according to the present utility model;

fig. 5 is a schematic view of the present utility model in use with a guide.

The device comprises a 1-steel plate, a 101-main nail hole, a 102-locking pressurizing nail hole, a 102 a-hole I, a 102 b-hole II, a 2-sleeve, a 201-sleeve flange, a 202-convex edge, a 3-main nail, a 301-main nail head, a 301 a-blade groove, a 302-main nail flange, a 4-anti-rotation nail hole, a 5-cross nail, a 6-broken line, a 7-locking screw, an 8-guider, a 801-guiding sleeve and a 9-tail cap.

Detailed Description

The present utility model will be described in further detail with reference to the drawings and examples, in order to make the objects, technical solutions and advantages of the present utility model more apparent. It should be understood that the specific embodiments described herein are for purposes of illustration only and are not intended to limit the scope of the utility model.

Referring to fig. 1-5, the utility model provides an internal fixing device for femoral neck fracture, which comprises a steel plate 1, a sleeve 2, a main nail 3, a cross nail 5 and a tail cap 9.

The inner side surface of the steel plate 1 is matched with the anatomical form of the proximal outer side wall of the femur, so that the steel plate 1 can be well attached to cortical bone, the main nail 3 is provided with a firm base, the periphery of the steel plate 1 is in a blunt arc shape, the length of the steel plate is about 40mm, and the thickness of the steel plate is about 6 mm. For convenience of description of the arrangement requirements of other elements, it is now defined that when the medial surface of the steel plate is in anatomic engagement with the proximal lateral wall of the femur, the faces of the steel plate facing the anterior and posterior sides of the human hip are the anterior and posterior faces of the steel plate, respectively. Preferably, 2.0mm Kirschner wire nail holes are formed in the steel plate, so that the steel plate can be fixed in an auxiliary mode, and rotational displacement during operation is avoided.

The inner side of the lower end of the steel plate 1 is provided with a sleeve 2 for inserting a femur moment and allowing a main nail 3 to axially pass through, and the inner side of one end of the sleeve 2 far away from the steel plate 1 is provided with a sleeve flange 201 along the circumferential direction. The steel plate 1 is provided with a main nail hole 101, the sleeve 2 is connected to the main nail hole 101, and the sleeve 2 and the steel plate 1 are preferably of an integrated structure. The sleeve 2 is obliquely arranged on the inner side of the steel plate 1, and the included angle between the sleeve 2 and the steel plate 1 is 120 degrees, so that the anatomical state of the femoral head is met, and the femoral head is convenient to attach to the femoral head moment. Based on the sleeve 2 being inclined, the sleeve 2 is not entirely cylindrical, the sleeve 2 has a length of 30-40mm, the longest portion being about 40mm and the shortest portion being about 30mm. The inner diameter of the sleeve is about 12mm, the width of the flange of the sleeve is 2mm, the outer diameter of the sleeve is about 15mm, and the thickness of the sleeve is 3mm, so that the main nailing and tilting pressure caused by human body gravity during standing can be resisted. The diameter of the main nail is 10mm, and the diameter of the transverse nail is 4.0mm. The inner wall of the sleeve 2, which is close to the steel plate, is provided with threads, and the tail cap 9 can be connected with the sleeve 2 through threads after being inserted into the sleeve 2 from the main nail hole; the effect of tail cap 9 is to carry out the spacing to the slip position of main nail 3, according to the condition when clinical actual operation, selects tail cap 9 of suitable length for tail cap 9 installs the back and leaves about 5 mm's clearance with the main nail, prevents main nail 3 to withdraw from, realizes limited pressurization.

The side of the main nail 3 is provided with more than one anti-rotation nail hole 4 from the main nail head 301 to the middle part of the main nail, when in use, the anti-rotation nail hole 4 is positioned at the fracture end of the femoral head, the cross nail 5 is matched and connected with the anti-rotation nail hole 4, when in matched and connected, the cross nail 5 can prevent the fracture end of the femoral head from rotating unstably and prevent the main nail from cutting out of the femoral head in the fracture end, and when in installation, the furthest end of the cross nail 5 cannot protrude out of the surface of the femoral head, otherwise, the hip joint movement is limited. The number of the anti-rotation nail holes 4 is preferably three, and the central axis of the anti-rotation nail holes 4 is preferably perpendicular to the central axis of the main nail 3, so that the most stable locking is realized; the three anti-rotation nail holes 4 are arranged at intervals along the axial direction of the main nail 3. The three anti-rotation nail holes 4 are arranged to adapt to three types of fracture of the femoral neck, namely a subhead type fracture, a middle-neck type fracture and a basal type fracture (see three fracture lines 6 with different positions in figure 1), so that the utility model is simultaneously applicable to the three types of fracture, and when the anti-rotation nail hole 4 positioned in the fracture end of the femoral head is used, the anti-rotation nail hole 4 is selected to install the cross nail 5 according to different fracture positions, so that the cross nail 5 is beaten at the fracture end of the femoral head, and the axial circumferential displacement of the main nail 3 is locked. Thereby preventing unstable rotation of the fracture end of the femoral head caused by rotation and displacement of the main nail and preventing the main nail from cutting out the femoral head.

When the cross nail 5 is driven in, the central axis of the cross nail 5 is required to be perpendicular to the central axis of the main nail 3, the matched guide 8 can be adopted for positioning, the design of the guide 8 can refer to fig. 5, the matched guide is used for positioning and mounting as the prior art, the guide 8 is provided with a screw which can be in threaded fit connection with the inner wall of the sleeve 2 and a fixing device which is connected with other parts of the steel plate, the main nail hole 101 and other parts of the steel plate are connected in a positioning way through the screw, the guide 8 and the steel plate 1 can not move relatively any more, at this time, the main nail 3 slides to a far-end limit position, namely the joint of the main nail flange 302 and the sleeve flange 201, the guide sleeve 801 is arranged at the other end of the guide 8 and is exactly vertically directed to the anti-rotation nail hole 4, and the cross nail 5 is driven in along the position and the direction of the guide sleeve 801, namely the cross nail 5 can be just inserted into the anti-rotation nail hole 4.

A main nail flange 302 with the length of 10-15mm is circumferentially arranged on the outer side wall of the tail end of the main nail 3, and the main nail flange 302 is matched with the sleeve flange 201 to prevent the main nail 3 from slipping from the sleeve 2 when sliding, namely the maximum outer diameter of the main nail flange 302 is larger than the inner diameter of the sleeve flange 201; an anti-rotation structure for preventing the main nail 3 from rotating circumferentially is further arranged between the outer wall of the main nail 3 and the inner wall of the sleeve 2, and when the main nail 3 is sleeved into the sleeve 2 and connected through the anti-rotation structure, namely after the relative positions are locked, the extending direction of the central axis of the anti-rotation nail hole 4 is consistent with the front side surface of the steel plate 1 and the front and back directions between the rear side surfaces of the steel plate. Namely, when the inner side surface of the steel plate is attached to the anatomical form of the proximal outer side wall of the femur, the central axis of the anti-rotation nail hole 4 is also directed to the front side of the human hip, so that the transverse nail 5 is conveniently driven from the front side of the human hip.

Those skilled in the art can adopt the prior art to design the anti-rotation structure, for example, the main nail is close to the tail end and is arranged into a quadrangle, a hexagon and the like, and the inner wall structure of the sleeve 2 far away from the part of the steel plate 1 is arranged into a structure with the same shape as the tail end of the main nail, so that the anti-rotation structure can play a role in preventing the circumferential rotation of the main nail 3. The utility model also provides another embodiment, the anti-rotation structure is a matched groove and a convex rib 202, namely the outer wall of the main nail 3 is axially provided with the convex rib 202, the inner wall of the sleeve 2 is axially provided with the groove, or the outer wall of the main nail 3 is axially provided with the groove, the inner wall of the sleeve 2 is axially provided with the convex rib 202, and the convex rib 202 is in sliding connection in the groove to prevent the main nail 3 from rotating circumferentially; when the rib 202 is axially disposed on the inner wall of the sleeve 2, the main nail flange 302 is further provided with a notch matching with the rib 202, see fig. 2-3, which is a preferred embodiment of the present utility model. In both the above two modes, the groove or the rib is required to be arranged at a position which is far away from the steel plate as far as possible in the sleeve, and the length is 8-12cm, so that the tail cap 9 is not interfered in use. When the main nails are slidably connected in the sleeve 2 through the grooves and the ribs 202, namely, when the main nails 3 are sleeved into the sleeve 2 and connected through the anti-rotation structure, the extending direction of the central axis of the anti-rotation nail holes 4 is consistent with the front side surface of the steel plate 1 and the front and back directions between the rear side surfaces of the steel plate. Namely, when the inner side surface of the steel plate is attached to the anatomical form of the proximal outer side wall of the femur, the central axis of the anti-rotation nail hole 4 is also directed to the front side of the hip of the human body, so that the transverse nail 5 is conveniently driven from front to back from the front of the hip of the human body.

Through the combined action of the structures of the transverse nail 5 and the anti-rotation structure, the main nail 3 can be ensured not to rotate circumferentially and slide axially to cut out the femoral head when in use, thereby ensuring the clinical treatment effect and preventing complications such as fracture disunion, femoral head necrosis and the like.

Preferably, the main spike 3 is provided with a hollow passage along the central axis, which passes through the entire main spike 3 and can be passed through by a 2.5mm k-wire. Through the arrangement, the femoral head can be implanted by adopting the 2.5mm Kirschner wire for guiding, and then the main nail 3 is driven along the Kirschner wire, so that the purpose of minimally invasive is achieved.

When the fixing device is used, the femoral neck fracture is reduced by closing or cutting, 1-2 Kirschner wires are used for temporarily fixing the fracture, and the Kirschner wires for temporarily fixing the fracture need to avoid the screw position of the device; a guide needle (2.5 mm Kirschner wire) is placed in the femur neck by using a 120-degree angle guide device on the outer side wall of the proximal femur, and the position of the guide needle is the position of a main nail; the front side position piece of the femoral neck is seen through an X-ray machine, so that the guide pin is ensured to be positioned at the middle lower part of the femoral neck when the front position piece is arranged, the distal end is positioned in the subchondral bone of the femoral head, and meanwhile, the guide pin of the side position piece is positioned at the central position of the femoral neck; measuring the length of the guide pin in the bone by a measurer, determining the length specification of the main pin, and drilling holes along the guide pin by using a hollow drill to manufacture a bone tunnel; inserting the main nails 3 into the sleeve 2, and connecting the steel plate 1 by the guide device so that the main nails 3 slide to a far-end limit position, namely, the joint of the main nail convex edges 302 and the sleeve flange 201; the main nail 3 and the sleeve 2 are partially placed into a bone canal opened by an electric drill, the steel plate 1 is attached to the outer side wall of the proximal end of femur, the guide needle is withdrawn, 2.0mm Kirschner wire nail holes in the steel plate 1 are utilized, 2.0mm Kirschner wires are driven into the steel plate for temporary positioning, and rotational displacement during operation is avoided; due to the limiting action of the grooves and the ribs 202, the main nails 3 cannot rotate circumferentially, so that the direction of the anti-rotation nail holes 4 is not changed, and due to the action of the main nail flanges 302 and the sleeve flanges 201, the main nails 3 cannot slip from the sleeve 2. At this time, the other end of the guide 8 is provided with a guide sleeve 801 which points to the front of the hip of the human body and just points to the anti-rotation nail hole 4, and the cross nail 5 is driven in along the position and the direction of the guide rod, so that the cross nail 5 can be just inserted into the anti-rotation nail hole 4, the guide 8 is withdrawn, and all the kirschner wires are withdrawn. The transverse nails 5 and the main nails 3 are crossed and locked at the fracture ends of the femoral head, the circumferential rotation of the main nails 3 is limited, the cutting-out resistance is good, and the transverse nails can axially slide as a whole, so that the fracture ends are pressurized, the fracture healing is promoted, and the fracture nonunion, femoral head necrosis and internal fixation failure risks are reduced.

Regarding the selection of the specification of the tail cap 9, in clinical practice, if the fracture is well reduced and the fracture end has no gap, a static locking mode can be adopted, so that no gap exists between the tail cap 9 and the main nail. However, in clinic, the fracture end may be separated, that is, the fracture end has a gap, so that the fracture end needs to be powered, for example, when a patient steps on the ground, the bone slides down with the main nail, and a power is needed at this time, so that a certain gap is needed between the tail cap 9 and the main nail, so that the fracture end can be pressurized, the gap is limited, and healing is promoted.

Preferably, the head of the main nail 3 is a conical nail head, at least three blades are arranged on the conical nail head along the length direction of the main nail 3, each blade is arranged along the circumferential direction of the conical nail head, and a blade groove 301a is arranged between two adjacent blades. Three blade structures are 15mm long, the blade structures are hammered into bone, more bone mass is reserved, the bearing area is increased by the blade groove surfaces, and rotation of the femoral head and penetration of the internal fixing device out of the femoral head are well prevented.

Through the operation, the main nail and the cross nail are driven into the femoral head, the fracture is subjected to reduction connection, at the moment, although the cross nail 5 and the main nail 3 are used for cross locking of the fracture end of the femoral head, the circumferential rotation of the main nail 3 is limited, the cross nail has good cutting resistance, and the cross nail can axially slide as a whole, so that the fracture end is pressurized, the healing of the fracture is promoted, and the fracture nonunion, femoral head necrosis and internal fixation failure risks are reduced. But the steel plate is not better fixed at this time and is also required to be locked; and when the fracture end is provided with a gap, if some operations can be performed, the gap is reduced, and healing can be better promoted.

Therefore, the present device is more preferably provided with locking press nail holes above the sleeve 2 on the steel plate 1, and locking screws 7 and/or common screws are provided in the nail holes. More preferably, the locking screw 7 is parallel to the main spike 3. In order to improve the adaptability of the present utility model, it is preferable that the locking nail hole is a locking pressing nail hole 102, the locking pressing nail hole 102 includes a hole one 102a and a hole two 102b which are mutually communicated, the inner diameters of the hole one 102a and the hole two 102b are the same, the hole one is far away from the main nail hole, the inner wall of the hole one 102a is provided with an internal thread for connecting a locking screw, the hole two is close to the main nail hole, the inner wall of the hole two 102b is a smooth surface for connecting a common screw 7, so that the present utility model can be used for punching the locking screw 7 and the common screw. The common screw 7 has the diameter of 5.0mm and the length of 60mm-100mm, can enter the fracture end, and the locking screw 7 has the diameter of 5.0mm and the length of 60mm-100mm. If the fracture has a gap, the fracture end can be pressed by a common screw, and if the reduction is good, the locking screw 7 is used.

When the fixing device is used, the whole implantation sequence is as follows:

firstly, fracture reduction and temporary fixation of 1-2 Kirschner wires are carried out, the Kirschner wires avoid the screw position of the device, a guide needle (2.5 mm Kirschner wire) is placed in the position of the guide needle, namely the main nail position, after the X-ray fluoroscopy machine ensures that the guide needle is good in position, the main nail specification is determined by measuring the length of the guide needle in bones, after an electric drill is used for perforating, the main nail 3 is inserted into a sleeve 2, the guide is connected with a steel plate 1, so that the main nail 3 slides to a far-end limiting position, a guide sleeve 801 of the guide 8 is opposite to an anti-rotation nail hole 3, the main nail 3 and the sleeve 2 are placed into a bone canal opened by the electric drill, the steel plate 1 is attached to the outer side wall of the proximal end of a femur, and the guide sleeve 801 of the guide is pointed to the front of the hip of a human body. The position and orientation of the guide sleeve 801 along the guide 8 drives the cross pin 5 in, i.e. just so that the cross pin 5 is inserted into the anti-rotation pin hole 4, out of the guide 8 and the k-wire.

Observing through an X-ray perspective machine, if the fracture is well reduced and the fracture end has no gap, punching a locking screw 7 on the first hole 102a to perform static locking; so that there is no gap between the main pin 3 and the tail cap 9.

If the fracture end is separated, namely the fracture end is provided with a gap, a common screw 7 is driven into the second hole 102b, the fracture end is pressurized, the gap is reduced, the hole is drilled into the femoral head, a measurer measures the depth of a bone canal, and the common screw with proper length is selected for locking. The measurer measures the distance between the main nail and the steel plate, and the tail cap 9 with proper length is selected to be connected in the sleeve 3, so that a gap of about 3-5mm exists between the tail cap 9 and the main nail, and dynamic pressurization is carried out.

The above description is illustrative of the preferred embodiment of the present utility model and is not intended to limit the present utility model, but is to be construed as including any modifications, equivalents, and improvements made within the spirit and principles of the present utility model.

Claims (10)

1. An internal fixing device for femoral neck fracture is characterized by comprising a steel plate, a sleeve, a main nail, a cross nail and a tail cap; the inner side surface of the steel plate is matched with the anatomical form of the proximal outer side wall of the femur, when the inner side surface of the steel plate is attached to the anatomical form of the proximal outer side wall of the femur, the surfaces which define the front side and the rear side of the hip of a human body of the steel plate are respectively the front side surface of the steel plate and the rear side surface of the steel plate, the inner side of the lower end of the steel plate is provided with a sleeve which is used for inserting femur moment and allowing a main nail to axially pass through, the steel plate is provided with a main nail hole, the sleeve is connected at the main nail hole, the inner side of one end of the sleeve, far from the steel plate, is circumferentially provided with a sleeve flange, the inner wall of the sleeve, close to the steel plate, is provided with threads, and the tail cap can be connected with the sleeve through threads after being inserted into the sleeve from the main nail hole; the lateral surface of the main nail is provided with more than one anti-rotation nail hole from the head part of the main nail to the middle part of the main nail, and the transverse nail is used for being connected with the anti-rotation nail hole in a matching way; the outer side wall of the tail end of the main nail is circumferentially provided with a main nail flange with the length of 10-15mm, and the main nail flange is matched with the sleeve flange to prevent the main nail from slipping from the sleeve when sliding; and an anti-rotation structure for preventing the circumferential rotation of the main nail is further arranged between the outer wall of the main nail and the inner wall of the sleeve, and when the main nail is sleeved into the sleeve and is connected through the anti-rotation structure, the extending direction of the central axis of the anti-rotation nail hole is consistent with the front-back direction between the front side surface of the steel plate and the back side surface of the steel plate.

2. The internal fixation device for femoral neck fracture of claim 1, wherein: the anti-rotation structure is a groove and a convex rib which are matched with each other, namely, the outer wall of the main nail is provided with the convex rib along the axial direction, the inner wall of the sleeve is provided with the groove along the axial direction, or the outer wall of the main nail is provided with the groove along the axial direction, the inner wall of the sleeve is provided with the convex rib along the axial direction, and the convex rib is in sliding connection in the groove to prevent the circumferential rotation of the main nail; when the inner wall of the sleeve is provided with a convex rib along the axial direction, the flange of the main nail is also provided with a notch matched with the convex rib; the grooves or the ribs are arranged in the sleeve at positions which are far away from the steel plate as far as possible, and the length of the grooves or the ribs is 8-12cm; when the main nail is in sliding connection in the sleeve through the groove and the convex rib structure, the extending direction of the central axis of the anti-rotation nail hole is consistent with the front and back directions of the front side surface and the back side surface of the steel plate.

3. The internal fixation device for femoral neck fracture of claim 1, wherein: the number of the anti-rotation nail holes is three, the three anti-rotation nail holes are arranged at intervals along the axial direction of the main nail, and the central axis of the anti-rotation nail holes is mutually perpendicular to the central axis of the main nail.

4. The internal fixation device for femoral neck fracture of claim 1, wherein: the head of the main nail is a conical nail head, three blade lobes are arranged on the conical nail head along the length direction of the main nail, each blade lobe is arranged along the circumferential direction of the conical nail head, and a blade groove is formed between two adjacent blade lobes.

5. The internal fixation device for femoral neck fracture of claim 1, wherein: the main nail is provided with a hollow channel along the central axis, and the hollow channel penetrates through the whole main nail and can be used for passing a Kirschner wire with the diameter of 2.5 mm.

6. The internal fixation device for femoral neck fracture of claim 1, wherein: the steel plate is provided with a locking pressurizing nail hole above the sleeve, and a locking screw or a common screw is arranged in the locking pressurizing nail hole.

7. The internal fixation device for femoral neck fracture of claim 1, wherein: the sleeve is obliquely arranged on the inner side of the steel plate, and the included angle between the sleeve and the steel plate is 120 degrees.

8. The internal fixation device for femoral neck fracture of claim 1, wherein: the length of the sleeve is 30-40mm.

9. The internal fixation device for femoral neck fracture of claim 1, wherein: 2.0mm Kirschner wire nail holes are formed in the steel plate.

10. The internal fixation device for femoral neck fracture of claim 6, wherein: the locking pressurizing nail hole comprises a first hole and a second hole which are communicated with each other, the inner diameters of the first hole and the second hole are the same, the first hole is far away from the main nail hole, the inner wall of the first hole is provided with an internal thread for connecting a locking screw, the second hole is close to the main nail hole, and the inner wall of the second hole is a smooth surface for connecting a common screw.

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