Intramedullary bone cement supporting rod for proximal humerus fracture

Abstract

The invention relates to the technical field of orthopedic biomedical treatment, in particular to a proximal humerus fracture intramedullary bone cement supporting rod. The bone fracture plate comprises a bone fracture plate body, a plurality of first connecting holes and a plurality of second connecting holes are formed in one side of the bone fracture plate body in a penetrating mode, and solid bone nails are arranged in the first connecting holes. According to the device, bone cement is injected into a marrow cavity from an injection molding channel and an injection molding opening and then solidified into a rod body, the marrow cavity space is tightly filled, supporting structures are synchronously formed on the inner side and the outer side of the humerus through cooperation of a bone fracture plate and a bone cement supporting rod in the marrow cavity space, and therefore stress generated when arms of a patient move is evenly dispersed on the two sides of the humerus; the fixing stability is remarkably improved, the risk of internal fixation failure such as steel plate displacement and screw cutting is effectively reduced, and the bone cement supporting rods can further prevent displacement of fracture blocks, promote fracture repair, relieve extrusion and friction of surrounding tissue of a filling position, reduce inflammatory response and postoperative pain and improve the rehabilitation comfort of a patient.

Description

Technical Field

[0001] The present invention relates to the technical field of orthopedic biomedicine, in particular to an intramedullary bone cement support rod for proximal humeral fracture. Background Art

[0002] Proximal humeral fractures are a common osteoporotic fracture type in the elderly. Due to the prevalence of osteoporosis in elderly patients, the proximal humeral bone strength is significantly reduced. The fracture often presents with an "eggshell" humeral head and severe comminution of the medial column, leading to collapse of the medial support structure and loss of the neck-shaft angle. This complex fracture morphology poses significant challenges to traditional open reduction and plate and screw fixation techniques: on the one hand, compression defects in the cancellous bone make reduction difficult and difficult to maintain; on the other hand, the porous bone cannot provide sufficient holding force for internal fixation devices (such as plates and screws), resulting in an extremely high risk of screw cutting, plate displacement, and internal fixation failure (such as nail and plate dislocation) after surgery.

[0003] To solve the problem of lack of medial support, bone grafting technology is often used in existing technologies for filling and supporting, which is mainly divided into the following two methods: one is autologous bone transplantation, which requires taking bones from other parts of the patient's body (such as the ilium). This not only increases the surgical trauma and time, but more importantly, the bone mass and quality of autologous bones in elderly osteoporosis patients are often poor, making it difficult to provide effective structural support, and there is a risk of complications at the bone harvesting site; the other is allogeneic bone transplantation, which usually uses allogeneic fibula or femur segments for support. However, this type of allogeneic bone material is scarce, difficult to purchase, and extremely expensive. In addition, allogeneic bone transplantation also has potential problems such as immune rejection reactions, disease transmission risks, and high postoperative infection rates.

[0004] Therefore, how to effectively and safely reconstruct comminuted fractures, especially the stable support of the medial column, while overcoming the fixation difficulties caused by osteoporosis and reducing the risk of internal fixation failure, remains a difficult problem that needs to be solved in clinical practice. Summary of the Invention

[0005] The present invention provides an intramedullary bone cement support rod for proximal humeral fractures, wherein bone cement is injected into the medullary cavity of the humerus through an injection channel and an injection port provided in a hollow bone screw. After the bone cement fills the medullary cavity and solidifies, a bone cement support rod is formed and cooperates with a bone plate to form support on both the inner and outer sides of the humerus, thereby solving the problems in the above-mentioned background technology, namely: In the case of osteoporotic proximal humeral fractures in the elderly, the porous bone cannot provide effective support for traditional internal fixation with plates and screws. In bone transplantation technology, there are problems such as the difficulty of self-harvested bone to provide effective support, and the high cost of allogeneic bone and the potential for immune rejection.

[0006] To achieve the above-mentioned purpose, the intramedullary bone cement support rod for proximal humeral fracture includes a bone plate, a plurality of No. 1 connecting holes and a plurality of No. 2 connecting holes are formed on one side of the bone plate, a solid bone screw is arranged inside the No. 1 connecting hole, and a hollow bone screw is arranged inside the No. 2 connecting hole. The hollow bone screw includes an injection channel and a plurality of injection ports, and the injection ports are connected to the injection channel. After the hollow bone screw enters the interior of the humerus, bone cement is injected into the medullary cavity of the humerus through the injection channel and the injection port. The bone cement will fill the interior of the medullary cavity. After the bone cement solidifies, a bone cement support rod will be formed inside the humerus, which will cooperate with the bone plate to synchronously form support on the inside and outside of the humerus.

[0007] In the above technical solution, bone cement is injected into the medullary cavity through the injection channel and injection port of the hollow bone screw and then solidified into a rod, tightly filling the medullary cavity space. Through the cooperation of the bone plate and the bone cement support rod in the medullary cavity space, a support structure is simultaneously formed on the inside and outside of the humerus, so that the stress during the patient's arm movement is evenly dispersed on both sides of the humerus, significantly improving the fixation stability and effectively reducing the risk of internal fixation failure such as steel plate displacement and screw cutting. The bone cement support rod can also prevent the displacement of fracture fragments, promote fracture repair, reduce the extrusion and friction of the surrounding tissues of the filling area, reduce inflammatory response and postoperative pain, and improve the patient's recovery comfort.

[0008] In another technical solution, a sliding sleeve is provided on the outside of the hollow bone screw, and the sliding sleeve is used to cover the injection port during the period when the hollow bone screw enters the inside of the humerus to prevent bone chips from entering the inside of the injection channel through the injection port; a number of the injection ports are opened on the outside of the nail rod part, and the injection ports are evenly distributed along the axial direction of the nail rod part; the hollow bone screw includes a nail tail part, a nail rod part and a nail head part, the nail tail part is fixedly connected to the nail rod part, the nail rod part is threadedly connected to the nail head part, and the injection channel is opened inside the nail tail part and the nail rod part; the sliding sleeve is provided with two symmetrically distributed grooves on the outside, and the interior of the No. 2 connecting hole is fixedly connected with two The guide keys are symmetrically distributed and slidably connected to the grooves; a filling strip is fixedly connected to the inside of the groove, and the filling strip is made of a deformable elastic material. When the guide key is located inside the groove, the guide key abuts against the filling strip; a guide baffle is fixedly connected to the outside of the injection port, and the guide baffle is used to block bone chips from entering the injection port when the nail rod rotates; the opening direction of the guide baffle is opposite to the rotation direction when the hollow bone screw is screwed into the humerus, and is used to bounce off bone chips when the hollow bone screw is screwed into the humerus; an accommodating cavity is opened at one end of the sliding sleeve close to the injection port, and when the sliding sleeve covers the injection port, several of the guide baffles are located inside the accommodating cavity.

[0009] In this technical solution, during the process of screwing the hollow bone screw into the humerus, the sliding sleeve completely covers the injection port, and at the same time, a guide baffle is provided on the outside of the injection port, with the opening direction opposite to the rotation direction of the hollow bone screw when screwing into the humerus. When the hollow bone screw is screwed into the humerus, bone chips are bounced off, which can effectively prevent bone chips from clogging the injection port or entering the injection channel, thereby avoiding abnormal injection pressure and the risk of bone cement leakage caused by bone chips. In addition, the filling strip fills the groove, which can keep the outer wall of the sliding sleeve smooth, and prevent the groove from scratching the bone and causing additional damage during implantation.

[0010] Compared with the prior art, the present invention has the following beneficial effects: 1. In the intramedullary bone cement support rod for proximal humeral fractures, bone cement is injected into the medullary cavity through the injection channel and the injection port and then solidified into a rod body, tightly filling the medullary cavity space. Through the cooperation of the bone plate and the bone cement support rod in the medullary cavity space, a support structure is simultaneously formed on the inside and outside of the humerus, so that the stress during the patient's arm movement is evenly dispersed on both sides of the humerus, significantly improving the fixation stability and effectively reducing the risk of internal fixation failure such as steel plate displacement and screw cutting. The bone cement support rod can also prevent the displacement of fracture fragments, promote fracture repair, reduce the extrusion and friction of the surrounding tissues of the filling site, reduce inflammatory response and postoperative pain, and improve the patient's recovery comfort.

[0011] 2. In the intramedullary bone cement support rod for proximal humeral fracture, the sliding sleeve completely covers the injection port during the process of screwing the hollow bone screw into the humerus, which can effectively prevent bone chips from clogging the injection port or entering the injection channel, thereby avoiding abnormal injection pressure and the risk of bone cement leakage caused by bone chips. At the same time, a guide baffle is provided on the outside of the injection port with an opening direction opposite to the rotation direction of the hollow bone screw when it is screwed into the humerus. When the sliding sleeve moves to expose the injection port and the hollow bone screw is still rotating, bone chips can be bounced off, thereby preventing bone chips from entering the injection channel due to the medical staff's failure to stop the rotation of the hollow bone screw in time, thereby improving the safety of the surgical process. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 It is a schematic diagram of the overall structure of the present invention; Figure 2 Schematic diagram of the disassembled structure of the bone plate, solid bone screw and hollow bone screw in the present invention; Figure 3 Schematic diagram of the overall structure of the hollow bone screw of the present invention; Figure 4 This is a schematic diagram of the disassembled structure of the hollow bone screw after the sliding sleeve is cut away; Figure 5 For the present invention Figure 4 A magnified schematic diagram of the structure at center A; Figure 6 Schematic diagram of the state change before and after the injection port is exposed in the present invention; Figure 7 Schematic diagram of the state change of the hollow bone screw before and after it enters the second connecting hole; Figure 8 Schematic diagram of the overall structure of the bone cement support rod after forming in the present invention; Figure 9 Schematic diagram of the fit between the bone cement support rod and the humerus when implanted in the manner of Example 2 of the present invention.

[0013] The meaning of each number in the figure is: 1. Bone plate; 11. Connection hole No. 1; 12. Connection hole No. 2; 121. Guide key; 2. Solid bone screws; 3. Hollow bone screw; 31. Nail tail; 32. Nail shaft; 33. Nail head; 34. Injection channel; 341. Injection port; 35. Sliding sleeve; 351. Accommodating cavity; 36. Guide baffle; 37. Filling strip. DETAILED DESCRIPTION

[0014] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0015] Example 1 Currently, for osteoporotic proximal humeral fractures in the elderly, the porous bone is difficult to provide effective support for traditional internal fixation with steel plates and screws. In bone transplantation technology, there are problems such as the difficulty of self-obtained bone to provide effective support, and the high cost of allogeneic bone and the potential for immune rejection. The present invention provides an intramedullary bone cement support rod for proximal humeral fractures, see Figure 1 - Figure 5 As shown, it includes a bone plate 1, and one side of the bone plate 1 is penetrated by a plurality of No. 1 connecting holes 11 and a plurality of No. 2 connecting holes 12. A solid bone screw 2 is arranged inside the No. 1 connecting hole 11, and a hollow bone screw 3 is arranged inside the No. 2 connecting hole 12. The hollow bone screw 3 includes a nail tail 31, a nail rod 32 and a nail head 33. The nail tail 31 is fixedly connected to the nail rod 32, and the nail head 33 is threadedly connected to the nail rod 32. An injection channel 34 is opened inside the nail tail 31 and the nail rod 32, and a plurality of injection ports 341 connected to the injection channel 34 are evenly opened on the outside of the nail rod 32. A sliding sleeve 35 is arranged on the outside of the nail rod 32, and a guide baffle 36 is fixedly connected to one side of the plurality of injection ports 341.

[0016] Among them, see Figure 1 and Figure 2As shown, the shape of the bone plate 1 is wide at the top and narrow at the bottom. When a fracture occurs at the proximal end of the humeral head, the wider side at the top is used to connect to the humeral head, and the narrower side at the bottom is used to connect to the humeral body. The solid bone screw 2 and the hollow bone screw 3 respectively pass through the No. 1 connecting hole 11 and the No. 2 connecting hole 12 and are drilled into the interior of the humerus to connect the bone plate 1 and the two fractured humeri. The bone plate 1 fixes the position of the humerus and promotes the reconstitution of the fractured humerus. It should be noted that the hollow bone screws 3 are provided on both sides of the bone plate 1, and the specific number thereof is determined according to the specific surgical requirements. After the hollow bone screws 3 are drilled into the interior of the humerus, bone cement is injected into the medullary cavity of the humerus through the injection channel 34. The bone cement is finally injected into the medullary cavity through the injection port 341, and finally forms the following structure: Figure 8 The support rod shown can form an inner support in the medullary cavity of the humerus, and cooperate with the bone plate 1 to evenly disperse the stress on both sides of the humerus when the patient's arm moves, forming a more stable and durable support structure; the bone cement support rod can also be used to fill the medullary cavity to prevent the displacement of fracture fragments, which is conducive to promoting fracture repair, and the filling of the bone cement support rod can effectively reduce the extrusion and friction of the surrounding tissues at the medullary cavity filling site, has better fit, can effectively reduce the inflammatory response, and relieve the patient's pain.

[0017] Furthermore, since the bones of elderly patients are relatively fragile, large bone chips will be produced when the hollow bone screw 3 is drilled into the humerus. These bone chips may block the injection port 341 when the hollow bone screw 3 is drilled, or even enter the injection channel 34 from the injection port 341, which will cause a sudden increase in pressure when the bone cement is injected into the bone marrow cavity. The bone cement may penetrate from the fracture site into the fracture line, thereby hindering the healing of the humeral fracture site. Therefore, the sliding sleeve 35 is used to cover the injection port 341 when the hollow bone screw 3 enters the humerus to prevent bone chips from entering the injection port 341 during this process.

[0018] The following is a detailed disclosure of a structure of the sliding sleeve 35 to achieve the above-mentioned effect: See also Figure 4 、 Figure 5 and Figure 7 As shown, the sliding sleeve 35 is threadedly connected to the nail rod portion 32, and two symmetrical grooves are provided on the outside of the sliding sleeve 35. A filling strip 37 is fixedly connected inside the groove, and the filling strip 37 is made of medical-grade silicone. The inner wall of the No. 2 connecting hole 12 is fixedly connected to two symmetrically distributed guide keys 121, and the guide key 121 is slidably connected to the groove, and the guide key 121 conflicts with the filling strip 37.

[0019] See also Figure 6As shown, the specific process is as follows: first, the medical staff installs the sliding sleeve 35 to the outside of the nail rod 32 through a thread, and after ensuring that the sliding sleeve 35 covers the injection port 341, the nail head 33 is connected to the nail rod 32. Next, the medical staff opens a hole in the humerus for the hollow bone screw 3 to enter. After that, the medical staff aligns the two grooves of the hollow bone screw 3 with the two guide keys 121 and inserts the hollow bone screw 3 along the direction of the groove. After insertion, the medical staff uses a tool to twist the nail tail 31, so that the nail rod 32 and the nail head 33 rotate together. During this process, due to the limiting effect between the guide key 121 and the groove, the sliding sleeve 35 will not rotate with the hollow bone screw 3, but will slide on the nail rod 32, thereby gradually exposing the injection port 341.

[0020] See also Figure 7 As shown, after the guide key 121 enters the groove, it will squeeze the filling strip 37 and cause it to deform. During the movement of the sliding sleeve 35, the part of the filling strip 37 that is abutted by the guide key 121 is constantly changing, and the part that is out of abutment will be restored. The reason why the filling strip 37 is set inside the groove is that if the groove is not covered, when the sliding sleeve 35 enters the humerus, once the groove on the outer wall of the sliding sleeve 35 contacts the humerus, it will further cause wear of the humerus during the entry process. Filling the groove with the filling strip 37 can keep the outer surface of the sliding sleeve 35 cylindrical to avoid wear of the humerus by the groove.

[0021] Furthermore, a receiving cavity 351 is provided at one end of the sliding sleeve 35 close to the injection port 341. When the sliding sleeve 35 covers the injection port 341, a plurality of guide baffles 36 are arranged inside the receiving cavity 351. The opening of the guide baffle 36 faces in the opposite direction to the rotation direction of the hollow bone screw 3 when entering the humerus.

[0022] After the sliding sleeve 35 moves and exposes the injection port 341, the hollow bone screw 3 may fail to stop rotating in time due to the operation of the medical staff, resulting in some bone chips still entering the injection port 341 during the period from the injection port 341 being exposed to the time when the medical staff stops operating. At this time, since the opening direction of the guide baffle 36 is opposite to the rotation direction of the hollow bone screw 3 when entering the humerus, the guide baffle 36 will bounce off the bone chips during the rotation of the hollow bone screw 3, thereby further preventing bone chips from entering the injection port 341 and improving the safety of the device.

[0023] The working principle of this device is as follows: First, the medical staff uses a special drill bit and, based on the specific needs of the surgery, creates holes corresponding to the solid bone screws 2 and the hollow bone screws 3 at the patient's humeral fracture site. The medical staff then places the bone plate 1 between the upper and lower bones of the humeral fracture, with the wider end of the plate 1 corresponding to the head of the humerus and the narrower end below corresponding to the body of the humerus. The medical staff then screws the solid bone screws 2 and the hollow bone screws 3 into the corresponding holes, respectively. During this process, the medical staff first screws the solid bone screw 2 into the hole through the No. 1 connecting hole 11, and then places the hollow bone screw 3 in the No. 2 connecting hole 12, and ensures that the two grooves of the sliding sleeve 35 correspond to the two guide keys 121 in the No. 2 connecting hole 12. Then the medical staff inserts the two guide keys 121 into the grooves and gradually slides the hollow bone screw 3 into the corresponding hole on the humerus; when the hollow bone screw 3 cannot slide into the humerus by sliding, the medical staff connects the nail tail 31 with a tool and uses the tool to rotate the hollow bone screw 3 to continue to enter the hole. During this period, due to the limiting effect of the guide key 121 on the groove, the sliding sleeve 35 cannot rotate with the nail rod 32. As the nail rod 32 continues to penetrate deeper, the sliding sleeve 35 slides on the nail rod 32, thereby gradually exposing the injection port 341; After the hollow bone screw 3 is completely inserted into the hole, the medical staff can stop rotating the hollow bone screw 3, then connect the injection molding equipment to the injection molding channel 34 of the nail tail 31 and inject bone cement. The bone cement is finally injected into the medullary cavity of the humerus from the injection molding port 341. By continuously injecting bone cement, the bone cement will gradually fill the medullary cavity of the humerus to form a supporting rod. During the injection molding process, the medical staff should monitor the injection amount of bone cement through X-ray observation technology to avoid excessive or insufficient injection of bone cement. If the injection port 341 is exposed until the medical staff stops operating, some bone chips may still enter the injection port 341. At this time, because the opening direction of the guide baffle 36 is opposite to the rotation direction of the hollow bone screw 3 when entering the humerus, the guide baffle 36 will bounce the bone chips away during the rotation of the hollow bone screw 3, thereby further preventing bone chips from entering the injection port 341. After the bone cement injection is completed, the medical staff can disconnect the injection equipment from the injection channel 34 and suture the patient's wound. After the support rod formed by the bone cement solidifies, it can form an inner support in the medullary cavity of the humerus, and cooperate with the bone plate 1 to evenly disperse the stress during the patient's arm movement on both sides of the humerus, forming a more stable and durable support structure. At the same time, the bone cement support rod can also be used to fill the medullary cavity to prevent the displacement of the fracture fragments, which is beneficial to promote fracture repair. The filling of the bone cement support rod can effectively reduce the extrusion and friction of the surrounding tissues at the medullary cavity filling point, and has better fit.

[0024] Example 2 This example provides another method for shaping and implanting a bone cement support rod, which includes the following steps: Step 1: First, the medical staff performs X-ray or CT scan on the patient's 1-2 cm below the surgical neck of the humerus. The medical staff then analyzes the shape of the location based on the scan results.

[0025] Step 2: After analyzing the shape of the location, medical staff will shape the bone cement raw materials so that the formed bone cement support rod fits the shape of the location.

[0026] Step 3: After the bone cement solidifies, the medical staff performs surgery on the patient's position and fits the bone cement support rod at the position. Finally, the medical staff uses a solid bone screw 2 to fix the bone cement support rod to the patient's humerus.

[0027] For details, see Figure 9 As shown, when the bone cement support rod is installed according to the above steps, the bone cement support rod fits in the inner concave surface of the surgical neck. For older people, this part is more fragile than that of young people. Therefore, when the bone cement support rod is installed in this position, it can further fit the humerus while providing more stable support for the inner concave surface. When shaping, the end of the bone cement support rod should have the same or similar curvature as the surgical neck of the patient's humerus.

[0028] Furthermore, medical tool processing factories can mass-produce bone cement support rods of different sizes based on the approximate shape of the surgical neck of the humerus of ordinary people. In this way, during surgery, medical staff can directly use bone cement support rods that have been prepared in advance and matched in size according to the results of X-ray or CT scans, reducing the manual shaping steps during the operation and improving surgical efficiency.

[0029] It should be noted that the average length of the surgical neck concavity of ordinary people is roughly between 8 and 15 mm, while the medullary cavity of the elderly may expand due to osteoporosis. Therefore, when factories mass-produce bone cement support rods of different sizes, the size can be increased by 10% to 20% accordingly.

[0030] The above shows and describes the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The above embodiments and descriptions are merely preferred examples of the present invention and are not intended to limit the present invention. Various changes and improvements may be made to the present invention without departing from the spirit and scope of the present invention. Such changes and improvements fall within the scope of the present invention. The scope of protection claimed in the present invention is defined by the appended claims and their equivalents.

Claims

1. An intramedullary bone cement support rod for proximal humeral fracture, comprising a bone plate (1), characterized in that: A plurality of No. 1 connection holes (11) and a plurality of No. 2 connection holes (12) are provided through one side of the bone plate (1), a solid bone screw (2) is provided inside the No. 1 connection hole (11), a hollow bone screw (3) is provided inside the No. 2 connection hole (12), the hollow bone screw (3) includes an injection channel (34) and a plurality of injection ports (341), the injection ports (341) are connected to the injection channel (34), after the hollow bone screw (3) enters the interior of the humerus, bone cement is injected into the medullary cavity of the humerus through the injection channel (34) and the injection port (341), the bone cement will fill the interior of the medullary cavity, and after the bone cement solidifies, a bone cement support rod will be formed inside the humerus, which will cooperate with the bone plate (1) to form support on both sides of the inside and outside of the humerus at the same time; A sliding sleeve (35) is provided on the outside of the hollow bone screw (3), and the sliding sleeve (35) is used to cover the injection port (341) when the hollow bone screw (3) enters the interior of the humerus, so as to prevent bone chips from entering the interior of the injection channel (34) through the injection port (341).

2. The intramedullary bone cement support rod for proximal humeral fracture according to claim 1, characterized in that: The hollow bone screw (3) comprises a nail tail portion (31), a nail shank portion (32) and a nail head portion (33); the nail tail portion (31) is fixedly connected to the nail shank portion (32); the nail shank portion (32) is threadedly connected to the nail head portion (33); and the injection molding channel (34) is opened inside the nail tail portion (31) and the nail shank portion (32).

3. The intramedullary bone cement support rod for proximal humeral fracture according to claim 2, characterized in that: The plurality of injection ports (341) are opened outside the nail rod portion (32), and the plurality of injection ports (341) are evenly distributed along the axial direction of the nail rod portion (32).

4. The intramedullary bone cement support rod for proximal humeral fracture according to claim 1, characterized in that: Two symmetrically distributed grooves are formed on the outside of the sliding sleeve (35), and two symmetrically distributed guide keys (121) are fixedly connected to the inside of the No. 2 connecting hole (12), and the guide keys (121) are slidably connected to the grooves.

5. The intramedullary bone cement support rod for proximal humeral fracture according to claim 4, characterized in that: A filling strip (37) is fixedly connected to the interior of the groove. The filling strip (37) is made of a deformable elastic material. When the guide key (121) is located inside the groove, the guide key (121) abuts against the filling strip (37).

6. The intramedullary bone cement support rod for proximal humeral fracture according to claim 2, characterized in that: A guide baffle (36) is fixedly connected to the outside of the injection port (341), and the guide baffle (36) is used to prevent bone chips from entering the injection port (341) when the nail rod portion (32) rotates.

7. The intramedullary bone cement support rod for proximal humeral fracture according to claim 6, characterized in that: The opening direction of the guide baffle (36) is opposite to the rotation direction of the hollow bone screw (3) when it is screwed into the humerus, and is used to bounce off bone chips when the hollow bone screw (3) is screwed into the humerus.

8. The intramedullary bone cement support rod for proximal humeral fracture according to claim 7, characterized in that: An accommodating cavity (351) is provided at one end of the sliding sleeve (35) close to the injection port (341). When the sliding sleeve (35) covers the injection port (341), the plurality of guide baffles (36) are located inside the accommodating cavity (351).

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