Femoral stem prosthesis

Abstract

The application relates to the technical field of artificial joint in medical orthopedics, in particular to a femoral stem prosthesis. The femoral stem prosthesis comprises a body, a drug loading device and a slow-release device; the drug loading device is at least partially installed in the body and is used for loading drugs; a flow channel is formed in the body, one end of the flow channel is communicated with the drug loading device, the other end of the flow channel is communicated with the outer surface of the body, so that the drugs in the drug loading device can flow to the outer surface of the body through the flow channel; the slow-release device is arranged on the flow channel and is used for controlling the speed of the drugs flowing to the outer surface of the body through the flow channel. The application has the advantages that: the slow-release device for controlling the speed of the drugs flowing to the outer surface of the body through the flow channel is arranged on the flow channel, the slow-release control is performed on the drugs flowing from the drug loading device to the outer surface of the body, the drugs are slowly released to the outer surface of the body in a very small flow, and the antibacterial function of the femoral stem prosthesis in each stage is realized.

Description

TECHNICAL FIELD

[0001] The application relates to the technical field of artificial joint in medical orthopedics, in particular to a femoral stem prosthesis. BACKGROUND

[0002] At present, in the clinic, there are still problems such as loosening, infection and pain of the femoral stem prosthesis in the femur after hip joint prosthesis replacement surgery. Infection is a disastrous problem for patients, and can even endanger life in severe cases. The infection after hip joint prosthesis replacement surgery can be divided into three stages according to the occurrence time of the symptoms. The first stage infection occurs within 3 months after the surgery. The second stage infection is a delayed infection, which occurs within two years after the surgery. The third stage infection is a late blood-borne infection, which occurs more than two years after the surgery.

[0003] In view of the problem of infection around the femoral stem prosthesis, the existing solutions mainly include: performing micro-nano treatment on the surface of the femoral stem prosthesis to prevent bacterial adhesion; and loading antibiotics or antibacterial metal ions in the coating layer of the prosthesis to achieve sterilization effect. Among them, the method of performing micro-nano treatment on the surface of the prosthesis can only reduce bacterial adhesion, and cannot fundamentally solve the infection problem. Moreover, the area that can be micro-nano treated on the surface of the prosthesis is extremely limited, so the effect is very small. The method of loading antibiotics or antibacterial metal ions in the coating layer of the prosthesis has a relatively complex process, and the antibiotics are usually released completely within a short time after the prosthesis replacement surgery, which is only effective for early infection, but ineffective for delayed infection and late infection. SUMMARY

[0004] Therefore, it is necessary to provide a femoral stem prosthesis capable of achieving antibacterial function at each stage.

[0005] A femoral stem prosthesis comprises a body, a drug loading device and a slow-release device. The drug loading device is at least partially installed in the body and is used for loading drugs. A flow channel is formed in the body, one end of the flow channel is communicated with the drug loading device, and the other end of the flow channel is communicated with the outer surface of the body, so that the drugs in the drug loading device can flow to the outer surface of the body through the flow channel. The slow-release device is arranged on the flow channel, and is used for controlling the speed of the drugs flowing to the outer surface of the body through the flow channel.

[0006] The femoral stem prosthesis provided by the application is provided with a flow channel in the body, the flow channel is communicated with the drug loading device and the outer surface of the body, and a slow-release device is arranged on the flow channel. The slow-release device can control the speed of the drugs flowing to the outer surface of the body through the flow channel, so that the drugs can be slowly released to the outer surface of the body at a very small flow rate, and the antibacterial function of the femoral stem prosthesis at each stage after the surgery can be achieved.

[0007] In one embodiment, the slow-release device comprises a piston rod, the femoral stem prosthesis further comprises a shell, the shell is at least partially disposed on the outer surface of the body, and the shell is connected to the piston rod, the shell is capable of driving the piston rod to move to control the speed of the drug flowing from the flow passage to the outer surface of the body.

[0008] It can be understood that, since the shell is at least partially disposed on the outer surface of the body, the shell extending out of the outer surface of the body is capable of cooperating with the human femur, so that the shell serves as a trigger to trigger the movement of the piston rod, and the shell is capable of driving the human femur to move when the hip joint moves, the movement of the human femur causes the shell to be slightly deformed, and the slight deformation of the shell drives the piston rod to move, thereby controlling the speed of the drug flowing from the flow passage to the outer surface of the body.

[0009] In one embodiment, the slow-release device further comprises a slow-release body and a piston connected to the piston rod, the slow-release body is provided with a slow-release cavity, the piston is movably disposed in the slow-release cavity and divides the slow-release cavity into a first cavity and a second cavity which are not in communication with each other; the flow passage comprises a first passage and a second passage, two ends of the first passage are respectively connected to the drug carrier device and the first cavity, and two ends of the second passage are respectively connected to the first cavity and the outer surface of the body.

[0010] It can be understood that, by dividing the slow-release cavity into the first cavity and the second cavity by the piston, the movement of the piston in the slow-release cavity can change the pressure difference between the first cavity and the second cavity, thereby slowly releasing the drug in the drug carrier device to the outer surface of the body by the principle of suction.

[0011] In one embodiment, a first control valve is arranged on the second passage, and the first control valve is capable of controlling the one-way flow of the drug from the slow-release device to the outer surface of the body.

[0012] It can be understood that, by arranging the first control valve capable of controlling the one-way flow of the drug from the slow-release device to the outer surface of the body on the second passage, the backflow of the drug in the drug carrier device and the body fluid on the outer surface of the body is avoided.

[0013] In one embodiment, the femoral stem prosthesis further comprises a transmission mechanism connected between the piston rod and the shell, under the action of the hip joint force, the shell is capable of driving the piston rod to move through the transmission mechanism to control the speed of the drug in the drug carrier device flowing from the first passage to the second passage.

[0014] It can be understood that, by connecting the transmission mechanism between the piston rod and the shell, the transmission mechanism is used as a conductor for transmitting the force on the shell to the piston rod, thereby ensuring that the piston rod can move better along the axis direction of the slow-release body.

[0015] In one embodiment, the transmission mechanism includes a first connecting rod, a second connecting rod and a third connecting rod which are rotatably connected to each other, one end of the first connecting rod, the second connecting rod and the third connecting rod converges at a point and is rotatably connected, the other end of the first connecting rod is rotatably connected in the body, the other end of the second connecting rod is rotatably connected to the piston rod, and the other end of the third connecting rod is rotatably connected to the shell.

[0016] In one embodiment, the drug loading device includes a connecting portion and a drug loading portion which are connected to each other, the drug loading portion is detachably installed in the body through the connecting portion, a drug loading cavity for loading drugs is arranged in the drug loading portion, and the drug loading cavity is in communication with the flow-through channel.

[0017] It can be understood that, by detachably installing the drug loading portion in the body through the connecting portion, the antibacterial function of the femoral stem prosthesis at each stage can be realized by replacing the drug loading device through minimally invasive surgery without revision of the femoral stem, which greatly reduces the operation difficulty of the doctor and the surgical pain of the patient, and the type of antibiotic can be changed when replacing the drug loading device to prevent the occurrence of bacterial immunity caused by long-term use of the same drug.

[0018] In one embodiment, a communication pipe in communication with the drug loading cavity is arranged on the connecting portion, and one end of the communication pipe extends out of the body to be in communication with the joint cavity in the human body.

[0019] It can be understood that, by extending one end of the communication pipe out of the body to be in communication with the joint cavity of the human body, the normal movement of the piston in the slow-release cavity is ensured.

[0020] In one embodiment, a second control valve is arranged on the communication pipe, and the second control valve can control the one-way flow of the drug from the communication pipe to the drug loading cavity.

[0021] It can be understood that, by arranging the second control valve on the communication pipe, which can control the one-way flow of the drug from the communication pipe to the drug loading cavity, the backflow of the drug in the drug loading cavity to the joint cavity through the communication pipe is avoided.

[0022] In one embodiment, the body has a mounting hole, and the connecting part is threadedly connected to the wall of the mounting hole; or, the connecting part is snapped into the wall of the mounting hole.

[0023] Compared with the prior art, this application provides a sustained-release device on the flow channel to control the speed at which the drug flows through the flow channel to the outer surface of the body, thereby controlling the sustained release of the drug flowing from the drug-carrying device to the outer surface of the body, so that the drug is released to the outer surface of the body at an extremely small flow rate, thereby achieving the antibacterial function of the femoral stem prosthesis at various stages. Attached Figure Description

[0024] To more clearly illustrate the technical solutions in the embodiments of this application or the conventional technology, the drawings used in the description of the embodiments or the conventional technology will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0025] Figure 1 This is a schematic diagram of the femoral stem prosthesis structure provided in this application;

[0026] Figure 2 for Figure 1 A magnified view of the structure at point A in the middle;

[0027] Figure 3 This is a schematic diagram of the structure of the femoral stem prosthesis provided in this application placed inside the human femur.

[0028] Reference numerals: 100, femoral stem prosthesis; 10, body; 11, flow channel; 111, first channel; 112, second channel; 12, mounting hole; 20, drug delivery device; 21, connecting part; 22, drug delivery part; 221, drug delivery cavity; 23, connecting tube; 30, sustained-release device; 31, sustained-release body; 32, sustained-release cavity; 321, first cavity; 322, second cavity; 33, piston; 34, piston rod; 40, housing; 50, first control valve; 51, second control valve; 60, transmission mechanism; 61, first connecting rod; 62, second connecting rod; 63, third connecting rod; 70, femur; 71, medullary cavity. Detailed Implementation

[0029] To make the above-mentioned objectives, features, and advantages of this application more apparent and understandable, the specific embodiments of this application are described in detail below with reference to the accompanying drawings. Many specific details are set forth in the following description to provide a thorough understanding of this application. However, this application can be implemented in many other ways different from those described herein, and those skilled in the art can make similar modifications without departing from the spirit of this application. Therefore, this application is not limited to the specific embodiments disclosed below.

[0030] It should be noted that when a component is referred to as being "fixed to" or "set on" another component, it can be directly on the other component or there may be an intermediate component. When a component is considered to be "connected to" another component, it can be directly connected to the other component or there may be an intermediate component present. The terms "vertical," "horizontal," "upper," "lower," "left," "right," and similar expressions used in this application's specification are for illustrative purposes only and do not represent the only possible implementation.

[0031] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this application, "multiple" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0032] In this application, unless otherwise expressly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature and the second feature are in indirect contact through an intermediate medium. Furthermore, "above," "over," and "on top" the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0033] Unless otherwise defined, all technical and scientific terms used in this application have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used in this application is for the purpose of describing particular embodiments only and is not intended to be limiting of the application. The term "and / or" as used in this application includes any and all combinations of one or more of the associated listed items.

[0034] Please see Figures 1 to 3The present invention provides a femoral stem prosthesis 100. This femoral stem prosthesis 100 is used in total hip replacement surgery to be installed into the medullary cavity 71 of the patient's femur 70, so that the patient can restore the physiological function of the hip joint to a certain extent, thereby achieving the purpose of treating the hip joint.

[0035] Currently, in clinical practice, problems such as loosening, infection, and pain still exist in the femoral stem prosthesis within the femur after hip replacement surgery. Infection is a catastrophic problem for patients, and in severe cases, it can even be life-threatening. Infection after hip replacement surgery can be divided into three stages based on the timing of symptom onset: Stage I infection occurs within 3 months after surgery; Stage II infection is delayed infection, occurring within 2 years after surgery; and Stage III infection is late hematogenous infection, occurring after 2 years after surgery.

[0036] Existing solutions for periprosthetic infection of the femoral stem are mainly: micro- and nano-treatment of the femoral stem prosthesis surface to prevent bacterial adhesion; and loading antibiotics or antibacterial metal ions into the surface coating of the femoral stem prosthesis to achieve a bactericidal effect. However, micro- and nano-treatment of the prosthesis surface only reduces bacterial adhesion and does not fundamentally solve the infection problem. Furthermore, the area on the prosthesis surface suitable for micro- and nano-treatment is extremely limited, thus its effectiveness is minimal. Loading antibiotics or antibacterial metal ions into the surface coating is technically complex, and antibiotics are usually released within a short time after prosthesis replacement surgery, making it effective only for early infections and ineffective against delayed or late-stage infections.

[0037] To address the problems existing in current femoral stem prostheses, one embodiment of the present invention provides a femoral stem prosthesis 100, which includes a body 10, a drug-carrying device 20, and a sustained-release device 30. The drug-carrying device 20 is at least partially installed within the body 10 and is used to load a drug. A flow channel 11 is provided within the body 10, with one end of the flow channel 11 connected to the drug-carrying device 20 and the other end connected to the outer surface of the body 10, so that the drug in the drug-carrying device 20 can flow through the flow channel 11 to the outer surface of the body 10. The sustained-release device 30 is disposed on the flow channel 11 and is used to control the speed at which the drug flows through the flow channel 11 to the outer surface of the body 10.

[0038] It's important to note that existing methods of coating the femoral stem prosthesis with antibiotics or antibacterial metal ions for sterilization suffer from limitations. Since the antibiotics are typically released shortly after the replacement surgery, they only exert their inhibitory effect on bacteria in the early stages of infection. After the antibiotics have dissipated, the femoral stem prosthesis loses its antibacterial function, leading to delayed and late-onset infections within two years and two years post-surgery, respectively. These infections necessitate a second-stage revision surgery. This involves surgically removing the femoral stem prosthesis from the femur, placing a spacer, thoroughly cleaning the wound, and controlling the infection before performing a second revision surgery. However, the infection rate after revision surgery is significantly higher than after the initial replacement, failing to address the root cause of the problem.

[0039] In this application, by providing a sustained-release device 30 on the flow channel 11, the sustained-release device 30 is used to control the speed at which the drug flows through the flow channel 11 to the outer surface of the body 10, thereby controlling the sustained release of the drug flowing from the drug-carrying device 20 to the outer surface of the body 10, so that the drug is released to the outer surface of the body 10 at an extremely small flow rate, thereby slowing down the release rate of the drug, and thus enabling the femoral stem prosthesis 100 to achieve effective antibacterial action in both delayed and late infection stages.

[0040] like Figure 1 and Figure 2 As shown, the sustained-release device 30 includes a sustained-release body 31, a piston rod 34, and a piston 33 connected to the piston rod 34. The sustained-release body 31 is provided with a sustained-release cavity 32, and the piston 33 is movably disposed in the sustained-release cavity 32, dividing the sustained-release cavity 32 into a first cavity 321 and a second cavity 322 that are not interconnected. The flow channel 11 includes a first channel 111 and a second channel 112. The two ends of the first channel 111 are respectively connected to the drug delivery device 20 and the first cavity 321, and the two ends of the second channel 112 are respectively connected to the first cavity 321 and the outer surface of the body 10.

[0041] Reference Figure 1 It should be noted that the sustained-release device 30 uses the pump principle. When the piston rod 34 drives the piston 33 to move horizontally to the right, the second chamber 322 is compressed, and the drug flowing from the drug-carrying device 20 into the first channel 111 is drawn into the first chamber 321. When the piston rod 34 drives the piston 33 to move to the left, the drug drawn into the first chamber 321 is pushed out by the piston 33 and released to the outer surface of the body 10 through the second channel 112, thus realizing the entire drug release process.

[0042] It is worth noting that, in one embodiment of the present invention, the number of second channels 112 can be set to multiple. One end of the multiple second channels 112 converges at the sustained-release body 31 and is connected to the first cavity 321. The other end of the multiple second channels 112 is respectively connected to different positions on the outer surface of the body 10, thereby enabling the drug to be released to any position on the outer surface of the body 10, further enhancing the antibacterial effect of the drug on the body 10.

[0043] Furthermore, the femoral stem prosthesis 100 also includes a housing 40, which is connected to the piston rod 34. The movement of the housing 40 can drive the piston rod 34 to move, thereby controlling the speed at which the drug flows through the flow channel 11 to the outer surface of the body 10. The housing 40 is at least partially disposed on the outer surface of the body 10, and one end of the housing 40 is rotatably connected to the body 10, while the other end is connected to the piston rod 34. When the human body moves, the femoral head of the femur 70 is subjected to joint forces from the hip joint. Under the compression of the hip joint forces, the body 10 undergoes slight deformation. Since the outer surface of the body 10 is provided with the housing 40, the housing 40 will also be driven to move slightly when the body 10 undergoes slight deformation. At this time, the end of the housing 40 connected to the piston rod 34 rotates around the end of the housing 40 connected to the body 10, thereby driving the piston rod 34 to move. Furthermore, by slightly rotating one end of the piston rod 34 connected to the housing 40 around the other end connected to the body 10, the piston rod 34 drives the piston 33 to reciprocate slightly within the sustained-release chamber 32, thereby releasing the drug in the drug delivery device 20 little by little through the flow channel 11 onto the surface of the body 10 to exert the antibacterial effect of the drug.

[0044] The advantage of releasing the drug through the movement of the piston rod 34 is that the piston rod 34 will only move when the patient is moving and the hip joint applies joint force to the femoral stem prosthesis 100, driven by the slight movement of the housing 40. In other words, when the patient is resting, the hip joint does not apply joint force to the femoral stem prosthesis 100, and the piston rod 34 will not move under the influence of the housing 40. Therefore, the drug delivery device 20 does not continuously deliver the drug to the surface of the body 10 through the flow channel 11, which further slows down the drug delivery speed and prolongs the effective antibacterial time of the drug.

[0045] Specifically, to adapt to the shape of the human femur 70, the outer surface of the body 10 is arc-shaped, and the shell 40 is located on the outer surface of the body 10. To match the shape of the outer surface of the body 10, the shell 40 is also arc-shaped and fits tightly against the outer surface of the body 10. After the femoral stem prosthesis 100 is placed in the medullary cavity 71, the shell 40 is located between the outer surface of the body 10 and the inner surface of the femur 70. When the femur 70 is subjected to hip joint forces, the hip joint forces are directly transmitted to the shell 40.

[0046] In one embodiment of the present invention, the body 10 is made of a metallic material such as a nickel-chromium alloy or a nickel-titanium alloy. Of course, in other embodiments of the present invention, the body 10 may also be made of other metallic materials. In one embodiment of the present invention, the shell 40 is made of a metallic material such as a nickel-chromium alloy, a nickel-titanium alloy, or tantalum. For example, the shell 40 may be made of tantalum, which has better bioactivity, thus facilitating the connection between the shell 40 and the femur 70, thereby making the force transmission from the femur 70 to the shell 40 more direct. Of course, in other embodiments of the present invention, the shell 40 may also be made of other bioactive metallic materials or other metallic materials.

[0047] Furthermore, a first control valve 50 is provided on the second channel 112. The first control valve 50 can control the unidirectional flow of the drug from the sustained-release device 30 to the surface of the main body 10; that is, the first control valve 50 is a one-way valve. A second control valve 51 is provided on the first channel 111. The second control valve 51 can control the unidirectional flow of the drug from the drug-carrying device 20 to the sustained-release device 30; that is, the second control valve 51 is a one-way valve.

[0048] It should be noted that since the sustained-release device 30 uses the pump principle to release the drug, and the first channel 111 and the second channel 112 are respectively connected to both sides of the sustained-release body 31 and are both connected to the first cavity 321, when the piston rod 34 drives the piston 33 to move horizontally to the right, the fluid in the first cavity 321 and the second cavity 322 will both be subjected to a force that draws them into the first cavity 321. This causes the fluid in the first cavity 321 and the second cavity 322 to tend to flow into the first cavity 321. However, the second channel 112 is connected to the outer surface of the body 10, which means that when the piston rod 34 drives the piston 33 to move to the right, the body fluid on the outer surface of the body 10 will be drawn back into the first cavity 321, forming backflow, which will cause discomfort to the patient. To avoid this phenomenon, a first control valve 50 is installed on the second channel 112 to control the unidirectional flow of the drug from the sustained-release device 30 to the surface of the body 10. This ensures that the drug can only flow from the first cavity 321 into the second channel 112 and cannot flow back from the second channel 112 into the first cavity 321. Additionally, when the piston rod 34 drives the piston 33 to move to the left, the piston 33 generally forces the drug in the first cavity 321 into the first channel 111 and the second channel 112. However, if the drug enters the first channel 111 and then flows back, the drug release effect will be weakened. Therefore, a second control valve 51 is also needed on the first channel 111 to control the unidirectional flow of the drug from the drug-carrying device 20 to the sustained-release device 30. In this way, the drug in the first cavity 321 can be released to the surface of the body 10 through the second channel 112.

[0049] In one embodiment of the present invention, both the first control valve 50 and the second control valve 51 are capable of adjusting the opening degree of the valve port. Thus, by adjusting the valve opening degree, the flow rate of the drug can be controlled, thereby adapting to different drug dosage requirements. Since the severity of different patients' conditions varies, the required drug dosage will also differ. Before surgery, the valve opening degree is pre-set according to the different patients' conditions, and then the first control valve 50 and the second control valve 51 are installed in the main body 10. This method achieves targeted antibacterial treatment for patients after surgery.

[0050] It is worth noting that, in one embodiment of the present invention, the number of control valves having the function of controlling the flow rate of the drug by adjusting the opening of the valve port is at least one, and it needs to be set on the flow channel 11 connected to the drug delivery device 20.

[0051] Furthermore, the femoral stem prosthesis 100 also includes a transmission mechanism 60. The transmission mechanism 60 is connected between the piston rod 34 and the housing 40. Under the action of the joint force of the hip joint, the housing 40 can drive the piston rod 34 to move via the transmission mechanism 60, so as to control the speed at which the drug in the drug delivery device 20 flows from the first channel 111 to the second channel 112.

[0052] It should be noted that, since the piston rod 34 drives the piston 33 to move horizontally in the release chamber 32, and the housing 40 connected to one end of the piston rod 34 makes a circular motion with the end of the housing 40 connected to the body 10 as the center, in order to further ensure the stability of the piston rod 34 driving the piston 33 to move horizontally in the release chamber 32, in one embodiment of the present invention, a transmission mechanism 60 is connected between the piston rod 34 and the housing 40. The transmission mechanism 60 is used to convert the circular motion of the housing 40 into the horizontal motion of the piston rod 34, thereby avoiding the piston rod 34 being subjected to non-horizontal forces and failing to drive the piston 33 to move well in the release chamber 32.

[0053] In order to enable the transmission mechanism 60 to better convert the circular motion of the housing 40 into the horizontal motion of the piston rod 34, in one embodiment of the present invention, the transmission mechanism 60 is configured as a crank-connecting rod mechanism. Specifically, the transmission mechanism 60 includes a first connecting rod 61, a second connecting rod 62, and a third connecting rod 63 that are rotatably connected to each other. One end of the first connecting rod 61, the second connecting rod 62, and the third connecting rod 63 converges at a point and is rotatably connected. The other end of the first connecting rod 61 is rotatably connected to the body 10, the other end of the second connecting rod 62 is rotatably connected to the piston rod 34, and the other end of the third connecting rod 63 is rotatably connected to the housing 40. Thus, when the end of the housing 40 connected to the piston rod 34 rotates clockwise around the end of the housing 40 connected to the body 10, the third connecting rod 63 is pulled away from the sustained-release device 30, and the end of the first connecting rod 61 connected to the third connecting rod 63 rotates counterclockwise around the end of the first connecting rod 61 connected to the body 10. At this time, a horizontal force is applied to the second connecting rod 62, pulling it away from the sustained-release device 30. The piston rod 34 drives the piston 33 to move to the right in the sustained-release chamber 32, and the drug in the drug delivery device 20 is drawn into the first chamber 321; when the housing 40 rotates clockwise, the third connecting rod 63 is pulled away from the sustained-release device 30, and the piston rod 34 drives the piston 33 to move to the right in the sustained-release chamber 32, and the drug in the drug delivery device 20 is drawn into the first chamber 321; when the housing 40 rotates clockwise around the end of the body 10, the third connecting rod 63 is pulled away from the body 10, and the piston rod 34 rotates clockwise around the end of the housing 40 connected to ... When one end of the piston rod 34 rotates counterclockwise around the end of the housing 40 connected to the body 10, the third connecting rod 63 is pushed toward the direction of the sustained-release device 30. The end of the first connecting rod 61 connected to the third connecting rod 63 rotates clockwise around the end of the first connecting rod 61 connected to the body 10. At this time, a horizontal force is applied to the second connecting rod 62, which is pushed toward the direction of the sustained-release device 30. The piston rod 34 drives the piston 33 to move to the left in the sustained-release chamber 32. The drug in the first chamber 321 is pressed into the second channel 112 and flows to the outer surface of the body 10.

[0054] Of course, the transmission mechanism 60 is not limited to a crank-connecting rod mechanism. In other embodiments of the present invention, the transmission mechanism 60 can also be other structural forms such as an elastic beam unit, as long as it can realize the transmission of motion between the housing 40 and the piston rod 34. No limitation is made here.

[0055] Furthermore, the drug-carrying device 20 includes a connecting portion 21 and a drug-carrying portion 22 that are interconnected. The drug-carrying portion 22 is detachably installed within the main body 10 via the connecting portion 21. The drug-carrying portion 22 has a drug-carrying cavity 221 for loading drugs, and the drug-carrying cavity 221 is connected to the flow channel 11. The main body 10 has a mounting hole 12, and the drug-carrying portion 22 is detachably installed within the mounting hole 12 via the connecting portion 21.

[0056] It should be noted that existing femoral stem prostheses generally have mounting holes on their main body. During surgery, instruments connect to the main body through these mounting holes. After the main body is implanted into the femur, the instruments detach from the mounting holes and separate from the main body, thus achieving the implantation of the femoral stem prosthesis. In this application, the mounting hole on the main body 10 of the femoral stem prosthesis 100 can be used as the mounting hole 12 for the drug-loaded device 20, simplifying the manufacturing process. In one embodiment of the present invention, after the main body 10 is implanted into the femur 70, the drug-loaded device 20 is detachably installed using the mounting hole 12. This allows for the replacement of the drug-loaded device 20 through minimally invasive surgery, eliminating the need for re-engineering the femoral stem prosthesis 100 to achieve its antibacterial function at various stages. This greatly reduces the difficulty of the surgeon's operation and the patient's surgical pain. Furthermore, when replacing the drug-loaded device 20, the type of antibiotic can be changed to prevent the development of bacterial immunity caused by long-term use of the same drug.

[0057] Optionally, the connecting part 21 is threadedly connected to the wall of the mounting hole 12; or, the connecting part 21 is snap-fitted into the wall of the mounting hole 12, allowing the connecting part 21 to be more easily inserted into or removed from the mounting hole 12. Other methods can also be used to connect the connecting part 21 to the wall of the mounting hole 12, not limited to threaded connections or snap-fitting, as long as a detachable connection between the connecting part 21 and the wall of the mounting hole 12 can be achieved; no limitation is imposed here.

[0058] Furthermore, the connecting part 21 is provided with a connecting tube 23 that communicates with the drug-carrying cavity 221. One end of the connecting tube 23 is connected to the drug-carrying cavity 221, and the other end extends out of the main body 10 to communicate with the joint cavity inside the human body.

[0059] It should be noted that, since the sustained-release device 30 uses the suction principle to draw the drug in the drug-carrying chamber 221 into the first chamber 321 and release the drug drawn into the first chamber 321 from the second channel 112 to the outer surface of the body 10, based on this, in order to ensure the normal suction of the sustained-release device 30, both ends of the flow channel 11 need to be connected to the joint cavity of the human body. Therefore, a connecting pipe 23 connected to the joint cavity of the human body is provided on the connecting part 21 to ensure the normal movement of the piston 33 in the sustained-release chamber 32.

[0060] Of course, in order to prevent the drug in the drug-carrying cavity 221 from flowing back out through the connecting pipe 23, the second control valve 51 can also be set on the connecting pipe 23, thereby preventing the drug in the drug-carrying cavity 221 from flowing back into the joint cavity through the connecting pipe 23.

[0061] like Figure 3 As shown, the working process of the femoral stem prosthesis 100 provided in one embodiment of the present invention is as follows: When the patient moves, the hip joint applies a vertical joint force to the femoral head, thereby compressing the femur 70. Since the housing 40 is located between the femur 70 and the body 10, when the femur 70 is compressed, the body 10 undergoes slight deformation, thereby causing one end of the housing 40 connected to the third link 63 to perform a slight circular motion around the end of the housing 40 connected to the body 10. The movement of the housing 40 drives the first link 61 to connect to the third link 63. One end of piston 34 rotates slightly around the first connecting rod 61, connecting to the end of the main body 10. Then, the second connecting rod 62 pulls piston rod 34 to reciprocate horizontally. The reciprocating motion of piston rod 34 drives piston 33 to reciprocate within the sustained-release chamber 32, thereby realizing the suction process of sustained-release device 30. This allows sustained-release device 30 to continuously draw the drug from drug-carrying chamber 221 into the first chamber 321 and release it to the outer surface of main body 10 through second channel 112. When the patient is resting, piston 33 remains stationary within sustained-release chamber 32. In this way, the drug is released intermittently to the outer surface of main body 10, thereby prolonging the antibacterial time of femoral stem prosthesis 100 and enabling femoral stem prosthesis 100 to achieve antibacterial effects at various stages prone to infection.

[0062] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0063] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the patent application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the scope of protection of this application. Therefore, the patent protection scope of this application should be determined by the appended claims.

Claims

1. A femoral stem prosthesis, characterized in that, include: The main body (10), the drug delivery device (20), and the sustained-release device (30); The drug delivery device (20) is at least partially installed within the body (10), and the drug delivery device (20) is used to load drugs; The body (10) has a flow channel (11) inside. One end of the flow channel (11) is connected to the drug-carrying device (20), and the other end is connected to the outer surface of the body (10), so that the drug in the drug-carrying device (20) can flow through the flow channel (11) to the outer surface of the body (10). The sustained-release device (30) is disposed on the flow channel (11), and the sustained-release device (30) is used to control the speed at which the drug flows through the flow channel (11) to the outer surface of the body (10); The sustained-release device (30) includes a piston rod (34), and the femoral stem prosthesis also includes a housing (40). The housing (40) is at least partially disposed on the outer surface of the body (10), and the housing (40) is connected to the piston rod (34). The movement of the housing (40) can drive the piston rod (34) to move, so as to control the speed at which the drug flows through the flow channel (11) to the outer surface of the body (10) through the movement of the piston rod (34). The housing is configured as an arc-shaped structure.

2. The femoral stem prosthesis according to claim 1, characterized in that, The sustained-release device (30) further includes a sustained-release body (31) and a piston (33) connected to the piston rod (34). The sustained-release body (31) is provided with a sustained-release cavity (32). The piston (33) is movably disposed in the sustained-release cavity (32) and divides the sustained-release cavity (32) into a first cavity (321) and a second cavity (322) that are not interconnected. The circulation channel (11) includes a first channel (111) and a second channel (112). The two ends of the first channel (111) are respectively connected to the drug delivery device (20) and the first cavity (321), and the two ends of the second channel (112) are respectively connected to the first cavity (321) and the outer surface of the body (10).

3. The femoral stem prosthesis according to claim 2, characterized in that, The second channel (112) is provided with a first control valve (50), which can control the unidirectional flow of the drug from the sustained-release device (30) to the surface of the body (10).

4. The femoral stem prosthesis according to claim 2, characterized in that, The femoral stem prosthesis also includes a transmission mechanism (60), which is connected between the piston rod (34) and the housing (40). Under the action of hip joint force, the housing (40) can drive the piston rod (34) to move through the transmission mechanism (60) to control the speed at which the drug in the drug delivery device (20) flows from the first channel (111) to the second channel (112).

5. The femoral stem prosthesis according to claim 4, characterized in that, The transmission mechanism (60) includes a first link (61), a second link (62), and a third link (63) that are rotatably connected to each other. One end of the first link (61), the second link (62), and the third link (63) converges at a point and is rotatably connected. The other end of the first link (61) is rotatably connected to the body (10), the other end of the second link (62) is rotatably connected to the piston rod (34), and the other end of the third link (63) is rotatably connected to the housing (40).

6. The femoral stem prosthesis according to claim 1, characterized in that, The drug-carrying device (20) includes a connecting part (21) and a drug-carrying part (22) that are connected to each other. The drug-carrying part (22) is detachably installed in the body (10) through the connecting part (21). The drug-carrying part (22) is provided with a drug-carrying cavity (221) for loading drugs. The drug-carrying cavity (221) is connected to the flow channel (11).

7. The femoral stem prosthesis according to claim 6, characterized in that, The connecting part (21) is provided with a connecting tube (23) that communicates with the drug-carrying cavity (221). One end of the connecting tube (23) extends out of the body (10) to communicate with the joint cavity inside the human body.

8. The femoral stem prosthesis according to claim 7, characterized in that, The connecting pipe (23) is provided with a second control valve (51), which can control the unidirectional flow of the drug from the connecting pipe (23) to the drug-carrying chamber (221).

9. The femoral stem prosthesis according to claim 8, characterized in that, The main body (10) has a mounting hole (12), and the connecting part (21) is threadedly connected to the wall of the mounting hole (12); Alternatively, the connecting part (21) engages with the wall of the mounting hole (12).

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