CN216777191U

CN216777191U - Intramedullary nail and intramedullary nail assembly

Info

Publication number: CN216777191U
Application number: CN202123272792.2U
Authority: CN
Inventors: 张柳云; 朱威威; 林建东; 赵东; 刘梦星
Original assignee: Wuhan Mindray Technology Co Ltd
Current assignee: Wuhan Mindray Technology Co Ltd
Priority date: 2021-12-23
Filing date: 2021-12-23
Publication date: 2022-06-21
Anticipated expiration: 2031-12-23

Abstract

The application discloses intramedullary nail and intramedullary nail subassembly, an intramedullary nail, including the nail pole, the nail pole is equipped with first passageway, and first passageway extends to the distal end terminal surface of nail pole from the near-end terminal surface of nail pole, and first passageway is formed by the inner wall of nail pole, and the inner wall of nail pole is equipped with first chamfer with the junction of the distal end terminal surface of nail pole. In the application, the first chamfer is arranged on the end face of the far end to serve as an inner chamfer at the outlet of the first channel, so that the intramedullary nail is conveniently drawn out to penetrate through the instrument guide pin of the first channel after being installed in place.

Description

Intramedullary nail and intramedullary nail assembly

Technical Field

The application belongs to the technical field of medical instruments, and particularly relates to an intramedullary nail and an intramedullary nail assembly.

Background

When a patient's bone is fractured, different bone screw assemblies are usually selected to connect the fractured bones according to different fracture positions.

In the related art, when a fracture occurs in the bone of the extremities, such as femur, tibia, etc., usually, a nail hole is drilled in the medullary cavity of the bone, and an instrument guide pin is inserted into the nail hole, and then an intramedullary nail is inserted into the nail hole along the guide of the instrument guide pin. Wherein, still need to take out the apparatus guide pin from nail way downthehole after the intramedullary nail inserts nail way hole, however in the correlation technique the apparatus guide pin is taken out comparatively inconvenient.

SUMMERY OF THE UTILITY MODEL

Embodiments of the present application provide an intramedullary nail and intramedullary nail assembly to facilitate removal of a mechanical guide pin from a medullary cavity of a bone after insertion of the intramedullary nail into the medullary cavity.

The embodiment of the application provides an intramedullary nail, including the nail pole, the inside of nail pole is equipped with first passageway, first passageway is followed the near-end terminal surface of nail pole extends to the distal end terminal surface of nail pole, first passageway by the inner wall of nail pole forms, the inner wall of nail pole with the junction of the distal end terminal surface of nail pole is equipped with first chamfer.

Optionally, the nail stem comprises:

the first pipe body is an arc-shaped bent pipe;

one end of the second tube body is connected with one end of the first tube body, and the end face of the near end is positioned at the free tail end of the second tube body; and

and one end of the third pipe body is connected with the other end of the first pipe body, and the far end face is positioned at the free tail end of the third pipe body.

Optionally, the outer surface of the third pipe body is provided with one or more first grooves.

Optionally, in at least one radial section of the third tubular body:

the radius of curvature of the inner contour line of all the first grooves is R1;

the diameter of an inscribed circle of the inner contour line of all the first grooves is D4, and the inscribed circle of the inner contour line of all the first grooves is coaxially arranged with the first channel;

the inner diameter of the first channel is D3;

wherein R1 > (D3-D4)/2.

Optionally, a second locking hole is formed in the third pipe body, the second locking hole is a kidney-shaped hole, and the second locking hole is located on one side, far away from the distal end face, of the first groove.

Optionally, a second locking hole is formed in the third pipe body, the second locking hole penetrates through the third pipe body along the radial direction of the third pipe body, and a third chamfer is arranged at an opening on only one side of the second locking hole.

Optionally, in the axial direction of the second tube, a distance from an intersection point of the axis of the second tube and the axis of the third tube to the proximal end face is less than or equal to 90 mm;

the axis of the second tube and the axis of the third tube form an included angle of 174 ° to 176 °.

Optionally, the second tube body is provided with a first locking hole, and a radial cross section of the first locking hole is a non-circular cross section;

the included angle between the axis of the first locking hole and the axis of the third pipe body is 40-70 degrees;

the distance from the intersection point of the axis of the first locking hole and the axis of the second tube body to the proximal end face is 30-50 mm.

Optionally, at least a portion of the second tubular body has a non-circular cross-section in a radial cross-section.

Optionally, the nail rod is provided with a second groove, the second groove penetrates through the side wall of the first channel formed by the nail rod, and the second groove extends from the proximal end face to the distal end face.

Optionally, a second chamfer is arranged at the joint of the outer surface of the nail rod and the distal end face.

In a second aspect, embodiments of the present application also provide an intramedullary nail assembly including an intramedullary nail according to any one of the first aspect.

In the embodiment of the application, after the instrument guide pin inserting needle is inserted into the medullary cavity, the instrument guide pin can be positioned at the outer end part of the patient body and inserted into the first channel to form guiding matching, so that the intramedullary nail can be accurately inserted into the medullary cavity through the matching of the instrument guide pin and the first channel; conversely, when the intramedullary nail is inserted in place, the instrument guide pin can be conveniently taken out through the matching of the instrument guide pin and the first channel. Furthermore, in the process of drawing the instrument guide pin out of the first channel, the chamfer surface formed by the first chamfer can reduce or even avoid the mutual interference between the instrument guide pin and the distal end surface of the intramedullary nail. Therefore, the intramedullary nail provided by the embodiment of the application has the advantage of facilitating the extraction of the instrument guide pin.

Drawings

The technical solutions and advantages of the present application will become apparent from the following detailed description of specific embodiments of the present application when taken in conjunction with the accompanying drawings.

Fig. 1 is a schematic structural view of an intramedullary nail provided in an embodiment of the present application.

Fig. 2 is a cross-sectional view of the intramedullary nail of fig. 1 taken along the direction a-a.

Fig. 3 is an enlarged partial view at X of the cross-sectional view of the intramedullary nail of fig. 2.

Fig. 4 is a cross-sectional view of the intramedullary nail of fig. 1 taken along the direction B-B.

Fig. 5 is a cross-sectional view of the intramedullary nail of fig. 1 taken along the direction C-C.

Detailed Description

The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. It is to be understood that the embodiments described are only a few embodiments of the present application and not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present application.

The embodiment of the application provides an intramedullary nail and an intramedullary nail assembly, so that an instrument guide pin can be conveniently taken out in a surgical process.

An intramedullary nail is applied to an intramedullary nail assembly. The intramedullary nail assembly is used for connecting and fixing a plurality of sections of fractured bones in a fracture operation. For example, the intramedullary nail assembly may be suitable for femoral fractures and may also be suitable for tibial fractures, which is not limited by the embodiments of the present application. In the following, the technical solution of the embodiment of the present application will be further explained and explained by taking the intramedullary nail assembly as an example for femoral fractures.

The intramedullary nail assembly may include an intramedullary nail and a locking nail. The fractured multi-joint bone can be respectively fixed with the intramedullary nail in a screw joint way through the locking nail so as to connect the fractured multi-joint femoral bone.

In actual surgery, the end of the femur having the greater trochanter (i.e., the end of the femur near the hip) is referred to as the proximal end, while the end of the femur away from the greater trochanter (i.e., the end of the femur near the ankle) is referred to as the distal end. Typically, a cut is made at the apex of the greater trochanter of the femur in communication with the intramedullary canal of the femur, and a staple hole is drilled from the proximal end of the femur toward the distal end through the cut and through the fractured multi-segmented femur. At the moment, the intramedullary nail is inserted into the nail path hole from the incision, and then the multi-section thighbone is respectively screwed and fixed with the intramedullary nail through the locking nail. During the operation, the end of the intramedullary nail inserted into the nail way hole first is called the distal end of the intramedullary nail, and the end of the intramedullary nail inserted into the nail way hole last is called the proximal end of the intramedullary nail.

Referring to fig. 1 and 2, fig. 1 is a schematic structural view of an intramedullary nail according to an embodiment of the present application, and fig. 2 is a cross-sectional view of the intramedullary nail shown in fig. 1 taken along a direction a-a.

The intramedullary nail may include a nail shaft 100. The shank 100 is hollow such that a first passageway 10 is provided in the shank 100. The first channel 10 extends from the proximal end face 31 of the stem 100 to the distal end face 41 of the stem 100 to enable the instrument guide pin to pass through the first channel 10 of the stem 100.

The technical solutions of the embodiments of the present application are further explained and illustrated below with reference to specific surgical procedures:

the instrument guide pin may be pre-inserted into the intramedullary canal prior to insertion of the nail shaft 100 into the intramedullary canal. The end of the instrument guide pin outside the patient's body is then inserted into the first channel 10 of the nail shaft 100 so that the instrument guide pin and the first channel 10 of the nail shaft 100 form a guiding fit, and the nail shaft 100 can be accurately inserted into the medullary cavity. Conversely, when the nail shaft 100 is inserted into the medullary cavity, the instrument guide needle can be conveniently withdrawn from the medullary cavity through the first channel 10.

Referring to fig. 3, fig. 3 is an enlarged partial view of the intramedullary nail shown in fig. 2 at the position X in cross section. The first channel 10 is formed by the inner wall of the shank 100, the junction of the inner wall of the shank 100 and the distal end face 41 of the shank 100 being provided with a first chamfer 42. The first chamfer 42 may be a straight chamfer or a round chamfer, which is not limited in the embodiments of the present application.

In the related art, a head is arranged at one end of the instrument guide pin inserted into the far end of the medullary cavity, and the outer diameter of the head is larger than that of other parts, so that a section difference is formed between the head of the instrument guide pin and the other parts. At this time, if the first chamfer 42 is not provided, the step difference of the instrument guide pin is easily interfered with the distal end surface 41 in the process of withdrawing the instrument guide pin, so that the instrument guide pin is not smooth or even clamped on the distal end surface 41 in the process of withdrawing the instrument guide pin. In contrast, by providing the first chamfer 42 in the embodiment of the present application, the head of the instrument guide pin can be guided by the chamfer formed by the first chamfer 42, so that the head of the instrument guide pin can be smoothly inserted into the first channel 10. Therefore, the intramedullary nail of the embodiment of the application has the advantage of easy extraction of the instrument guide pin.

As shown in FIG. 1, the proximal maximum outer diameter of the shank 100 is greater than the distal outer diameter of the shank 100. It will be appreciated that the inner diameter of the distal end of the intramedullary canal is smaller than the inner diameter of the proximal end of the intramedullary canal. Thus, the proximal maximum outer diameter of the shank 100 being greater than the distal outer diameter of the shank 100 may allow the shank 100 to better match the intramedullary canal of the femur.

As shown in fig. 2, the shank 100 may include a first tube 20, a second tube 30, and a third tube 40.

The first pipe 20 is an arc-shaped elbow. One end of the second tube 30 is connected to one end of the first tube 20. The proximal end face 31 is located at the free end of the second tube 30. One end of the third tube 40 is connected to the other end of the first tube 20, and the distal end face 41 is located at the free end of the third tube 40. Therefore, in the present embodiment, the first channel 10 may extend from the end surface of the free end of the second tube 30 to the end surface of the free end of the third tube 40.

As shown in FIG. 2, the maximum outer diameter of the second tube 30 is smaller than the maximum outer diameter of the third tube 40 to match the shape of the femoral medullary cavity with a smaller distal inner diameter and a larger proximal inner diameter. Alternatively, the outer diameters of the first rod body and the second rod body may be the same, which is not limited in this embodiment.

Wherein, due to the first tube 20, the whole nail rod 100 can be regarded as a bent pipe. It will be appreciated that during surgery, an incision is typically made at the greater trochanter of the patient's femur to insert an intramedullary nail into the intramedullary canal of the femur. And in the coronal plane of the patient, there is a certain arc between the greater trochanter of the femur and the femoral shaft. Accordingly, the medullary cavity of the femur also has a curvature between the greater trochanter and the femoral solid. Therefore, the shank 100 is integrally formed in the shape of an elbow, which may allow for an improved fit of the intramedullary nail to the patient's medullary cavity.

As shown in fig. 2, the axis of the second tube 30 and the axis of the third tube 40 are at an angle α, which is between 174 ° and 176 °. It will be appreciated that, based on anatomical analysis of the human femur, the greater trochanter apex of the femur is preferably notched to insert the intramedullary nail into the medullary canal. The incision is located on the axis of the greater trochanter, which is at an angle of 174 ° to 176 ° to the axis of the femoral shaft in the coronal plane. Thus, an angle α of 174 ° to 176 ° may facilitate insertion of the intramedullary nail into the intramedullary canal of the femur during the surgical procedure at the greater trochanter of the femur.

As shown in fig. 2, the distance L1 from the intersection point of the axis of the second tube 30 and the axis of the third tube 40 to the proximal end surface 31 in the axial direction of the second tube 30 is L1 equal to or less than 90 mm. It will be appreciated that, based on anatomical analysis of the human femur, the greater trochanter apex of the femur is preferably notched to insert the intramedullary nail into the medullary canal. The average distance between the vertex of the greater trochanter of the femur and the bending part of the femoral shaft is 90 mm. Therefore, when L1 is less than or equal to 90 mm, it is possible to prevent the free end of the second tube 30 from protruding out of the femur after the intramedullary nail is inserted into the medullary canal, so that the second tube 30 can cause compression and/or irritation to the musculature outside the femur.

In some embodiments, as shown in fig. 1 and 2, the first tube 20 and the second tube 30 are integrally formed.

Alternatively, the first and

second tubes

20, 30 may be detachably connected, so that the first and

second tubes

20, 30 having different sizes may be selected for assembly according to the patient's femur length. For example, the first tube 20 and the second tube 30 may be fixed by a snap fit or a screw fit, which is not limited in the embodiments of the present application.

As shown in fig. 1, the second tube 30 is provided with a first locking hole 32, the first locking hole 32 being adapted to fit a locking nail, such as a proximal locking nail, to threadedly fix the proximal end of the bone and the intramedullary nail.

The radial cross-section of the first locking hole 32 may be a non-circular cross-section. Correspondingly, the proximal locking pin is a non-cylindrical rod-shaped structure similar to the first locking hole 32, and further the proximal locking pin is matched with the inner wall of the first locking hole 32 to limit the proximal locking pin from rotating after penetrating through the first locking hole 32.

As shown in fig. 2, the axis of the first locking hole 32 and the axis of the third tube 40 form an angle β, which is between 40 ° and 70 °. It will be appreciated that by anatomical analysis of a human femur, there is an angle between the femoral neck and the femoral shaft of the femur on the coronal plane of between 110 ° and 140 °. Therefore, the angle beta is between 40 and 70 degrees, so that the proximal locking nail can penetrate into the femur from the side of the femur solid opposite to the femur neck along the axis direction of the femur neck, and the proximal locking nail penetrates into the femur and then is inserted into the femur neck after first penetrating through the first locking hole. Furthermore, the mounting stability of the proximal locking nail can be increased by increasing the connecting area of the proximal locking nail and the femur, so that the intramedullary nail is more firmly mounted.

As shown in fig. 2, in order to allow the proximal locking pin in the first locking hole 32 to be inserted into the medullary cavity of the femoral neck more accurately, the intersection point of the axis of the first locking hole 32 and the axis of the second tube 30 is located at a distance L2 from the proximal end surface 31, and L2 is 30 mm to 50 mm.

It will be appreciated that, based on anatomical analysis of a human femur, the distance from the greater trochanter apex of the femur to the axis of the femoral neck is between 30 mm and 50 mm. Thus, L2 between 30 mm and 50 mm allows for more accurate insertion of the proximal locking pin in the first locking hole 32 into the femoral neck.

Referring to fig. 4, fig. 4 is a cross-sectional view of the intramedullary nail of fig. 1 taken along the direction B-B. At least a portion of the second tube 30 has a non-circular cross-section in a radial cross-section. It will be appreciated that the spike hole formed in the medullary cavity by drilling is a circular hole. At least one radial section of the second tube 30 is a non-circular section, so that the contact area between the outer surface of the second tube 30 and the inner wall of the nail hole of the medullary cavity is reduced, and the pressure of the second tube 30 on the tissue in the medullary cavity is reduced, thereby reducing the influence of the second tube 30 on the blood supply of the tissue in the medullary cavity.

For example, the second tube 30 may be generally cylindrical, with the peripheral outer wall cut to form one or more flat surfaces. Alternatively, the second tube 30 may be an elliptic cylinder as a whole, which is not limited in the embodiment of the present application.

As shown in fig. 1, the nail shaft 100 is provided with a second groove 33. The second groove 33 forms a side wall of the first channel 10 through the shank 100. The second groove 33 extends from the proximal end face 31 towards the distal end face 41, so that an instrument for holding the intramedullary nail during surgery, such as a positioning protrusion on the lifting handle, can be snapped into the second groove 33 to position the lifting handle with the intramedullary nail.

As shown in fig. 1 and 2, the third tube 40 and the first tube 20 may be integrally formed.

Alternatively, the first tube 20 and the third tube 40 can be detachably connected, so that the first tube 20 and the third tube 40 with different sizes can be selected for assembly according to the change of the length of the femur of a patient. For example, the first tube 20 and the third tube 40 may be fixed by a snap fit or a screw fit, which is not limited in the embodiments of the present application.

As shown in fig. 2, the outer surface of the third tube 40 is provided with one or more first grooves 43. It can be understood that the spike hole formed in the medullary cavity of the patient by drilling is a circular hole, and the first groove 43 can reduce the contact area between the third tube 40 and the inner wall of the spike hole of the medullary cavity, so that the pressure of the third tube 40 on the tissue in the medullary cavity is reduced, thereby reducing the influence of the third tube 40 on the blood supply of the tissue in the medullary cavity.

Illustratively, the outer surface of the third tube 40 may be provided with one, two, three, or four first grooves 43. When the outer surface of the third pipe body 40 is provided with the first grooves 43, the first grooves 43 can be uniformly distributed around the circumference of the third pipe body 40, so that all the parts of the third pipe body 40 are stressed more uniformly, and the overall strength of the third pipe body 40 is improved.

Referring to fig. 5, fig. 5 is a cross-sectional view of the intramedullary nail of fig. 1 taken along the direction C-C. The technical solution of the embodiment of the present application will be further explained and explained by taking the example that the outer surface of the third tube 40 is provided with a plurality of first grooves 43.

In at least one radial section of the third tubular body 40, the inner contour of all the first grooves 43 has a radius of curvature R1, i.e., the first grooves 43 are arc-shaped grooves. Compared with the radial section of the first groove 43 being rectangular, the arc-shaped groove enables stress distribution of the groove wall at each position of the first groove 43 to be more uniform. The inscribed circle diameter of the inner contour line of all the first grooves 43 is D4. The inscribed circle of the inner contour of all first grooves 43 is arranged coaxially with first channel 10. The first passage 10 has an inner diameter D3. Wherein R1 > (D3-D4)/2. Further, the groove bottom of the first groove 43 may be made not to communicate with the first passage 10. It will be appreciated that the absence of the first groove 43 communicating with the first passage 10 may provide greater structural strength to the third body 40 where the first groove 43 is located.

As shown in fig. 5, the number of the first grooves 43 may be four. Also, in a radial section of the third tubular body 40, the inner contour of the first groove 43 forms an arc having an angle of less than 45 °. It will also be understood that, in a radial section of the third body 40, the angle between the perpendicular lines of the tangents to the two ends of the inner contour of the first groove 43 (i.e., the normal lines to the two ends of the inner contour of the first groove 43) is less than 45 °. Therefore, the depth of the first groove 43 in the radial direction of the third pipe body 40 can be made small to avoid the groove bottom of the first groove 43 from communicating with the first passage 10. Furthermore, the structural strength of the third tube 40 at the first groove 43 can be made higher.

As shown in fig. 1, the third tube 40 can be opened with a second locking hole 44. The second locking hole 44 is adapted to cooperate with a locking pin, such as a distal locking pin, to threadedly secure the femur to the third tube 40. The second locking hole 44 may or may not be in communication with the first channel 10, and is not limited in this embodiment. The second locking hole 44 may be a circular hole, a square hole, a hexagonal hole, or a kidney-shaped hole, which is not limited in the embodiment of the present application.

Hereinafter, taking the second locking hole 44 as a kidney-shaped hole as an example, the length direction of the kidney-shaped hole is the same as the axial direction of the third tube 40, and the technical solution of the embodiment of the present application will be further explained with reference to the operation process.

When the femur is fractured into two segments, one segment is the proximal end of the femur, the proximal end of the femur is connected and fixed with the second tube 30, and the other segment is locked to the third tube 40 by the distal locking pin and the kidney-shaped hole. Specifically, the distal locking nail can pass through the kidney-shaped hole, so that a part of the distal locking nail is fixedly connected with the inner wall forming the kidney-shaped hole, and a part of the distal locking nail is fixedly connected with the bone.

In the actual operation process, when the hole site for screwing the distal locking nail on the femur is unchanged and the relative position of the second tube 30 connected with the proximal end of the femur is also unchanged, the distal locking nail can be connected to different positions of the inner wall forming the kidney-shaped hole according to the actual fracture condition so as to adjust the relative positions of the two sections of femoral heads.

As shown in fig. 1, in order to ensure the strength of the third tube 40, the second locking hole 44 is located on the side of the first groove 43 away from the distal end surface 41, that is, in the axial direction of the third tube 40, the second locking hole 44 is offset from the first groove 43. It will be appreciated that providing the second locking hole 44 and the first groove 43 on the third tube 40 results in a reduction in the strength of the third tube 40. In contrast, if the second locking hole 44 and the first groove 43 partially overlap in the axial direction of the third tube 40, the strength of the third tube 40 at the overlapping position is greatly reduced, and the connection and fixation effect of the intramedullary nail on the bone is further affected.

As shown in fig. 1, the second locking hole 44 is a kidney-shaped hole, and the third pipe 40 includes a first arc surface 45 and a second arc surface 46 which are oppositely disposed along the axis of the third pipe 40 toward the first pipe 20. The axis of the first arc surface 45 and the axis of the second arc surface 46 are both perpendicular to the axis of the third pipe 40. The ends of the first circular arc surface 45 and the second circular arc surface 46 on the same side are connected through a straight surface to form a kidney-shaped hole.

As shown in fig. 1, the total length of the first, second and

third tubes

20, 30 and 40 in the axial direction of the third tube 40 is L. As shown in fig. 2, the distance L1 from the proximal end surface 31 is the intersection of the axis of the second tube 30 and the axis of the third tube 40 in the axial direction of the second tube 30. As shown in fig. 2, the distance from the intersection point of the axis of the second pipe 30 and the axis of the third pipe 40 to the axis of the second arc surface 46 is L3. As shown in fig. 2, the distance from the axis of the second arc surface 46 to the axis of the first arc surface 45 is L4. As shown in fig. 1, the first circular arc surface 45 and the second circular arc surface 46 each have a radius of curvature R2. As shown in fig. 2, the distance from the axis of the second arc surface 46 to the first groove 43 is L5. R2+ L4 < L5 < L-L1-L3 to make the overall strength of the third tube body 40 higher.

As shown in fig. 2, the second locking hole 44 may penetrate the third tube 40 in a radial direction of the third tube 40, and a third chamfer 47 is provided at only one side opening of the second locking hole 44. It will be appreciated that during the process of inserting the distal locking pin through the second locking hole 44, even if there is some misalignment between the distal locking pin and the second locking hole 44 of the third tube 40, the distal locking pin can still be guided to the correct position along the formed chamfered surface of the third chamfer 47 and inserted into the second locking hole 44. On the other hand, the opening of the second locking hole 44 on one side is not provided with the third chamfer 47, so that the processing process of the second tube body 30 can be simplified, and the processing cost and the processing time of the whole intramedullary nail can be saved. The third chamfer 47 may be a straight chamfer or a round chamfer, which is not limited in the embodiment of the present application.

As shown in FIG. 3, the junction of the outer surface of the shank 100 and the distal end face 41 is provided with a second chamfer 48. Specifically, a second chamfer 48 may be provided at the junction of the outer surface and the end surface of the third tube 40. Therefore, even if the intramedullary nail is misaligned with the nail way hole of the medullary cavity to some extent, the intramedullary nail can be guided to a correct position along the chamfer formed by the second chamfer 48 and inserted into the nail way hole. The second chamfer 48 may be a straight chamfer or a round chamfer, which is not limited in the embodiment of the present application.

In the foregoing embodiments, the descriptions of the respective embodiments have respective emphasis, and for parts that are not described in detail in a certain embodiment, reference may be made to the related descriptions of other embodiments.

The intramedullary nail and the intramedullary nail assembly provided by the embodiment of the application are described in detail, and the principle and the embodiment of the application are explained by applying specific examples, and the description of the embodiment is only used for helping to understand the method and the core idea of the application; meanwhile, for those skilled in the art, according to the idea of the present application, there may be variations in the specific embodiments and the application scope, and in summary, the content of the present specification should not be construed as a limitation to the present application.

Claims

1. The intramedullary nail is characterized by comprising a nail rod, wherein a first channel is arranged inside the nail rod, the first channel extends from the proximal end face of the nail rod to the distal end face of the nail rod, the first channel is formed by the inner wall of the nail rod, and a first chamfer is arranged at the joint of the inner wall of the nail rod and the distal end face of the nail rod.

2. The intramedullary nail of claim 1, wherein the shank comprises:

the first pipe body is an arc-shaped bent pipe;

3. The intramedullary nail of claim 2, wherein an outer surface of the third tube is provided with one or more first grooves.

4. The intramedullary nail of claim 3, wherein, in at least one radial cross section of the third tube:

the inner diameter of the first channel is D3;

wherein R1 > (D3-D4)/2.

5. The intramedullary nail of claim 3, wherein the third tube defines a second locking hole, the second locking hole being a kidney-shaped hole, the second locking hole being located on a side of the first recess remote from the distal end surface.

6. The intramedullary nail of claim 2, wherein the third tube defines a second locking hole extending through the third tube in a radial direction of the third tube, and wherein only one side of the second locking hole is defined by a third chamfer.

7. The intramedullary nail of claim 2, wherein, in the direction of the axis of the second tube, the distance from the intersection of the axis of the second tube and the axis of the third tube to the proximal end surface is less than or equal to 90 mm;

8. The intramedullary nail of claim 2, wherein the second tube defines a first locking hole having a non-circular cross-section in a radial cross-section;

9. The intramedullary nail of claim 2, wherein a radial cross-section of at least a portion of the second tube is a non-circular cross-section.

10. The intramedullary nail of any one of claims 1 to 9, wherein the shank defines a second groove extending through the shank forming a side wall of the first channel, the second groove extending from the proximal end surface toward the distal end surface.

11. The intramedullary nail of any one of claims 1 to 9, wherein a second chamfer is provided at a junction of the outer surface of the shank and the distal end face.

12. An intramedullary nail assembly comprising an intramedullary nail according to any one of claims 1 to 11.