CN217408939U - An intramedullary nail suitable for fracture of the lower segment of the humeral shaft - Google Patents

Abstract

The utility model relates to an intramedullary nail suitable for humeral shaft lower segment fracture, which comprises a main nail body along a straight line, wherein the main nail body comprises a proximal end part, a distal end part and a connecting section, the proximal end part and the distal end part are respectively positioned at the two axial ends of the main nail body; the free end of the distal portion is further provided with a bifurcate portion which is in a bifurcate arrangement and has a radian bending towards cancellous bone at the distal end of the humerus.

Description

An intramedullary nail suitable for fracture of the lower segment of the humeral shaft

technical field

The utility model relates to the field of medical devices, in particular to an intramedullary nail suitable for the fracture of the lower segment of the humeral shaft.

Background technique

Fractures of the lower part of the humeral shaft are also called fractures of the distal third of the humeral shaft. Because of the special anatomical shape of the lower part of the humeral shaft, it is the junction of the middle cylindrical part of the humerus and the distal triangle of the humerus, which is a weak mechanical distribution of the humerus. Therefore, it is also a predisposing site for fractures. Due to the irregular anatomy of the lower humerus, there is no uniform standard for the selection of surgical treatment options in clinical practice.

At present, the surgical options available in clinical practice mainly include: external stent fixation, humeral intramedullary nail fixation and open reduction and internal fixation with plate. External stent fixation is often used for open fractures. Antegrade intramedullary nailing of the humerus is the preferred option for humeral shaft fractures, but is less commonly used due to the limited distal distance in lower humeral shaft fractures. Retrograde intramedullary nailing of the humerus can be used for the treatment of lower humeral shaft fractures, but it has the risk of iatrogenic supracondylar fractures and iatrogenic axillary nerve injury, and it is not widely used in clinical practice. Open reduction and internal fixation are the commonly used surgical methods at present, and different surgical approaches and internal fixation methods have been reported in the literature. Due to the irregular shape and limited length of the distal end of the lower segment of the humeral shaft, the fixation strength of the single plate through the anterior or lateral approach is insufficient, and the early functional exercise has the risk of internal fixation failure. The strength of the double plate fixation is reliable and can meet the early functional exercise. The most clinical application is the posterior approach double plate fixation. However, this surgical approach requires the proximal separation and exposure of the radial nerve, and repeated traction during the operation has the risk of iatrogenic radial nerve injury. It has been reported that the risk of injury is as high as 16% to 31.1%. At the same time, due to the extensive dissection of soft tissue through the posterior approach, the blood supply of the fracture end is destroyed, and it has been reported that the postoperative fracture nonunion is up to 2% to 10%. Some scholars have tried double plate fixation through the medial and anterior approach, because the ulnar nerve and brachial artery need to be exposed through the medial surgical approach, and the anatomical structure is relatively complex, so it is rarely used in clinical practice.

For the fracture of the lower humeral shaft, various treatment plans have been tried because the anatomical structure of this region is special, and there is no certain surgical approach and internal fixation material that has absolute advantages for the combination of the lower humeral shaft. In recent years, with the emphasis on minimally invasive and refined treatment in trauma orthopaedics, improvement and innovation of surgical instruments is one of the ways to explore fracture treatment methods. Due to the lack of specific internal fixation materials for lower humeral shaft fractures, an intramedullary nail for lower humeral shaft fractures was proposed.

Utility model content

The utility model aims to provide an intramedullary nail suitable for the fracture of the lower segment of the humeral shaft.

The specific plans are as follows:

An intramedullary nail suitable for the fracture of the lower segment of the humeral shaft, comprising a main nail body along a straight line, the main nail body comprising a proximal end portion and a distal end portion located at two axial ends thereof respectively, and a connecting proximal end portion and a distal end portion. The connecting section of the distal end is characterized in that: the free end of the distal end is further provided with a bifurcated portion arranged in a bifurcation, and the bifurcation portion has an arc curved toward the cancellous bone of the distal end of the humerus.

Further, the distal end is also provided with a plurality of locking nail holes arranged in a cross manner, each locking nail hole is used to receive a locking nail, and a plurality of locking nails of the plurality of locking nail holes are arranged in a cross manner.

Further, the number of locking nail holes on the distal end is three.

Further, the end of the distal portion away from the connecting section is a wedge shape that gradually decreases toward the distal end.

Further, a middle-section transverse locking nail hole is provided in the middle of the connecting section.

Further, the proximal end is provided with a plurality of transverse locking nail holes staggered from the proximal end to the distal direction, and each transverse locking nail hole is used to receive a transverse locking nail, and the plurality of transverse locking nail holes are located in it. staggered radially.

Further, a functional area is further provided on the proximal end in the area between the transverse locking nail hole and the connecting section, and the functional area includes an oblique locking hole slantingly penetrating the proximal end, and a radially penetrating the proximal end. Pressurized holes and two K-wire holes at opposite ends of the functional area.

Further, the pressure hole is an oblong hole extending from the proximal end to the distal end.

Further, both the proximal end and the connecting section are cylindrical, and the outer diameter of the proximal end is larger than the outer diameter of the connecting section, and the connection between the proximal end and the connecting section is connected by a circular truncated section.

Compared with the prior art, the intramedullary nail suitable for the fracture of the lower segment of the humerus shaft provided by the utility model has the following advantages: the intramedullary nail suitable for the fracture of the lower segment of the humeral shaft provided by the utility model is provided with a bifurcation on the distal end of the main nail The bifurcation part has an arc that bends towards the cancellous bone of the distal humerus, so that the main screw can be properly tapped at the distal end after entering, so that the bifurcation part at the distal end of the main screw can be inserted into the cancellous bone of the distal humerus, so that the Strengthen the stability of the main nail fixation, while avoiding protruding from the olecranon fossa.

Description of drawings

Figure 1 shows a schematic view of the intramedullary nail in one view direction.

Figure 2 shows a schematic view of the intramedullary nail in another view direction.

Detailed ways

To further illustrate the various embodiments, the present invention provides accompanying drawings. These drawings are a part of the disclosure of the present invention, which are mainly used to illustrate the embodiments, and can be combined with the relevant description of the specification to explain the operation principles of the embodiments. With reference to these contents, those of ordinary skill in the art should be able to understand other possible embodiments and the advantages of the present invention. Components in the figures are not drawn to scale, and similar component symbols are often used to represent similar components.

The present utility model will now be further described with reference to the accompanying drawings and specific embodiments.

As shown in FIG. 1 and FIG. 2 , the present embodiment provides an intramedullary nail suitable for the fracture of the lower segment of the humeral shaft, which uses the anterolateral incision of the acromion to enter the humeral shaft through the belly of the supraspinatus muscle. The main nail body 1 along a straight line is included, so that the entrance of the main nail body 1 is entered through the supraspinatus muscle belly, which can avoid damage to the rotator cuff.

The main nail body 1 includes a proximal end portion 11 , a distal end portion 12 located at two axial ends thereof, and a connecting segment 13 connecting the proximal end portion 11 and the distal end portion 12 .

The proximal portion 11 and the connecting segment 13 are both cylindrical, and the outer diameter of the proximal portion 11 is larger than the outer diameter of the connecting segment 13, and the connection between the proximal portion 11 and the connecting segment 13 is realized by a circular truncated segment 14. connect. The proximal end portion 11 is provided with a plurality of transverse locking nail holes 111 staggered from the proximal end to the distal direction. Each transverse locking nail hole 111 is used to receive a transverse locking nail 21 , and the plurality of transverse locking nail holes 111 are staggered. It is arranged so that one or more of the corresponding transverse locking nail holes 111 can be selected for locking according to the actual situation during the operation, so that the intramedullary nail can have the best locking effect.

The proximal end portion 11 is further provided with a functional area 16 on the area between the transverse locking nail hole 111 and the connecting section 13 , and the functional area 16 includes an oblique locking hole 161 obliquely penetrating the proximal end portion 11 and penetrating the proximal end portion in a radial direction. 11 and the two K-wire holes 163 located at opposite ends of the functional area 16, the oblique locking hole 161 is used to receive a locking nail 22, the locking nail 22 and the horizontal locking nail 21 It has better locking effect; the compression hole 162 is an oblong hole extending from the proximal end to the distal end, so as to facilitate the intraoperative compression treatment according to the actual situation; the Kirschner wire hole 163 can be used for intramedullary nailing during the operation. Temporary fixation and positioning.

The middle part of the connecting section 13 is provided with a middle transverse locking screw hole 131, and the middle transverse locking screw hole 131 is used for receiving a transverse locking screw 21 from outside to inside, so as to increase the fixing strength of the lower section of the humeral shaft.

The proximal part connecting the distal part 12 and the connecting segment 13 is cylindrical, the length of the proximal part accounts for about 2/3 of the total length of the distal part, and the distal part far from the connecting segment gradually decreases towards the distal end. The length of the distal part accounts for about 1/3 of the total length of the distal part, so that the distal part 12 of the intramedullary nail can adapt to the anatomical shape of the intramedullary cavity of the humerus. Bifurcation 15, the bifurcation 15 has an arc that bends towards the cancellous bone of the distal end of the humerus, so that the main nail can be properly tapped to the distal end after entering, so that the bifurcation part 15 at the distal end of the main nail can be inserted into the distal end of the humerus. To enhance the stability of the main nail fixation and avoid protruding from the olecranon fossa.

The distal portion 12 is also provided with three locking nail holes 121 arranged in a cross manner, each locking nail hole 121 is used to receive a locking nail 22, and the three locking nails 22 are arranged in a cross manner to achieve a fixed locking effect. , and meet the limited length of the fracture end of the lower segment of the humeral shaft.

Although the present invention has been specifically shown and described in conjunction with preferred embodiments, it will be understood by those skilled in the art that changes in form and detail may be made without departing from the spirit and scope of the present invention as defined by the appended claims. Various changes are made to the present utility model, which are all within the protection scope of the present utility model.

Claims (8)

1. an intramedullary nail that is applicable to the fracture of the lower segment of the humeral shaft, comprising a main nail body along a straight line, the main nail body including being positioned at the proximal end, the distal end and the connection proximal end respectively at both ends of its axial direction It is characterized in that: the free end of the distal part is also provided with a bifurcated part arranged in a bifurcation, and the bifurcated part has an arc curved towards the cancellous bone of the distal end of the humerus. The distal end is also provided with a plurality of locking nail holes arranged in a cross manner, each locking nail hole is used to receive a locking nail, and a plurality of locking nails of the plurality of locking nail holes are arranged in an intersecting manner. 2 . The intramedullary nail according to claim 1 , wherein the number of locking nail holes on the distal end is three. 3 . 3 . The intramedullary nail according to claim 1 , wherein the end of the distal portion away from the connecting section is a wedge shape that gradually decreases toward the distal end. 4 . 4 . The intramedullary nail according to claim 1 , wherein a middle-section transverse locking nail hole is provided in the middle of the connecting section. 5 . 5 . The intramedullary nail according to claim 1 , wherein: the proximal end is provided with a plurality of transverse locking nail holes staggered from the proximal end to the distal end, and each transverse locking nail hole is used for receiving A horizontal locking nail, a plurality of horizontal locking nail holes are arranged alternately in its radial direction. 6 . The intramedullary nail according to claim 1 , wherein the proximal end is further provided with a functional area on the area between the transverse locking nail hole and the connecting section, and the functional area includes an oblique penetration through the proximal end. 7 . There is an oblique locking hole at the top, a pressure hole radially penetrating the proximal end, and two K-wire holes located at opposite ends of the functional area. 7 . The intramedullary nail according to claim 6 , wherein the compression hole is an oblong hole extending from the proximal end to the distal end. 8 . 8 . The intramedullary nail according to claim 1 , wherein the proximal part and the connecting section are both cylindrical, and the outer diameter of the proximal part is larger than the outer diameter of the connecting section, and the proximal part is the same as the outer diameter of the connecting section. A transitional connection is realized at the connection of the connecting segment through a circular truncated segment.

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