A filled bone grafting scaffold with thermal balance

Abstract

A thermally balanced filler bone graft scaffold includes a scaffold shell and a base. The scaffold shell has an inner cavity. The base has a multi-purpose chamber at its tail end and a heat convection tube assembly at its head end. The multi-purpose chamber is connected to the surface of the head end of the base via the heat convection tube assembly. The heat convection tube assembly connects the inner cavity of the scaffold shell with the multi-purpose chamber of the base. This provides a stable support base, promotes the bone integration process, achieves thermal balance of the overall scaffold, appropriately increases the internal temperature of the femoral head, accelerates local blood circulation in the femoral head, enhances cell activity, accelerates metabolism, promotes the proliferation and differentiation of osteocytes and other related cells, promotes angiogenesis and bone repair, facilitates gas exchange, promotes the drainage of effusion and gas, continuously releases intraosseous pressure, and provides storage space and pathways for therapeutic drugs and / or nutrients. This implant achieves multi-system synergy and promotes overall rehabilitation.

Description

Technical Field

[0001] This utility model relates to medical devices, and more specifically, to an implant for bone reconstruction, particularly a thermally balanced filler bone graft scaffold. It is primarily used to address problems of bone injury, necrosis, or defects, focusing on technical solutions to improve bone tissue reconstruction and microcirculation. Background Technology

[0002] Avascular necrosis of the femoral head, also known as ischemic necrosis (ONFH), is a common and difficult-to-treat disease in orthopedics. It originates from insufficient blood supply to the femoral head due to various factors, leading to ischemia and necrosis of bone cells, fracture of bone trabeculae, and collapse of the femoral head. Without effective treatment, approximately 80% of patients will experience femoral head collapse within 1-4 years, resulting in joint dysfunction and ultimately requiring total joint replacement surgery. The high cost of total joint replacement surgery places a significant economic burden on patients and society. Furthermore, because artificial joints have a limited lifespan, young and middle-aged patients still face various complications, revision surgeries, and secondary replacements after joint replacement. In addition, the difficulty and risks of repeat joint replacement surgery further exacerbate the economic burden on patients and significantly reduce their quality of life. Recent studies show that the incidence of avascular necrosis of the femoral head has been increasing year by year in recent years, and the age of onset is trending younger. Early treatment of avascular necrosis of the femoral head to preserve the patient's original joint function has always been a focus of attention.

[0003] Currently, there is no unified principle or consensus on the treatment of early-stage osteoarthritis of the femoral head (ONFH). Treatment plans are typically determined by physicians based on their knowledge, skills, and experience. Clinical treatments for early-stage ONFH can be divided into non-surgical and surgical treatments. Non-surgical treatments can relieve symptoms, but there is insufficient evidence to suggest that they can prevent femoral head collapse, protect joint function, delay joint replacement, or cure ONFH. Among the various hip-preserving surgical methods for early-stage ONFH, core decompression combined with filling and / or structural bone support using various bone repair biomaterials can effectively remove necrotic tissue, reduce intraosseous pressure, improve femoral circulation, promote angiogenesis, enhance bone formation, reduce the risk of proximal femoral fractures, and improve the treatment outcome of ONFH. Early removal of diseased tissue, filling and supporting the damaged area with implantable materials, and promoting bone regeneration are currently key directions in research and clinical treatment.

[0004] Current support implants are typically threaded into a drilled hole in the femoral head. The implant is inserted by applying force to its coronal end. These implants only provide internal support and cannot promote microcirculation regeneration or facilitate rapid integration of bone tissue with the implant. For example, conventional implants for femoral head necrosis, such as tantalum rods, only provide mechanical support and cannot halt the progression of the disease. Their osseointegration capacity is limited, failing to address insufficient blood supply to the femoral head. They cannot continuously release intraosseous pressure or metabolic byproducts from the osseointegration process. Tantalum rods often fail to achieve ideal osseointegration at the lesion site, potentially leading to bone resorption at the osseointegration interface and subsequent collapse.

[0005] In orthopedic clinical treatment, bone implants are important devices for repairing bone damage and treating bone diseases, and thermal balance has a significant impact on their therapeutic effect and patient recovery.

[0006] Under normal physiological conditions, the human body maintains thermal homeostasis in various tissues through blood circulation and metabolic regulation. Bone tissue physiological activities (such as osteoogenesis, osteoclast formation, and intercellular substance exchange) generate heat. Normally, blood circulation removes this heat, maintaining a suitable temperature and ensuring normal bone metabolism. However, after bone implantation, thermal balance is often disrupted. Taking the treatment of avascular necrosis of the femoral head as an example, the implant occupies space, disrupts local blood circulation, and affects heat exchange. Simultaneously, if the implant material and structure are inappropriate, they can hinder heat transfer, leading to abnormal heat distribution locally. Current clinical bone implants present significant problems with thermal balance. When the base and the outer shell of the implant are made of different materials, if the base is a non-metallic material such as a polymer, its low thermal conductivity creates thermal resistance, hindering heat conduction and causing heat to accumulate at the implant tip. This alters the bone cell microenvironment, affects cell signaling pathways, inhibits osteoblast activity, hinders bone matrix synthesis and mineralization, and may even promote excessive activation of osteoclasts, worsening the condition. Even when both the base and the outer shell are made of metal, thermal balance issues still exist. Different metals (such as pure titanium and cobalt-chromium alloys) have different thermal conductivity, and differences in processing technology and microstructure also affect heat transfer efficiency. Furthermore, current metal implants are not conducive to fluid drainage and external drug administration. The smooth surface of metal hinders fluid drainage; drug adsorption, penetration, and diffusion on metal surfaces are difficult, reducing the effectiveness of targeted therapy and impeding bone repair.

[0007] Post-implantation, the femoral head often experiences fluid and air accumulation, which interacts with thermal balance. In cases of small amounts of fluid or air accumulation, especially in the early stages of the disease, conservative treatment is insufficient to resolve the thermal balance issue. Larger amounts require aspiration, but aspiration carries risks of infection and damage to blood vessels and nerves, and it cannot directly drain the intraosseous fluid and air. Failure to promptly drain intraosseous fluid and air can increase local pressure, disrupt thermal balance and blood supply, creating a vicious cycle that hinders bone repair and can even lead to avascular necrosis. Currently, aspiration only treats the surrounding tissues and cannot specifically drain the intraosseous effusion or air. If the intraosseous effusion or air is not effectively treated and controlled, it is likely to recur, and the condition may even progress further.

[0008] Furthermore, poor integration during surgery also affects post-implantation thermal balance. Difficulty in fusion between the implant and surrounding tissues creates tiny gaps that hinder heat conduction. Improper surgical procedures leading to abnormal implant placement or damage can disrupt tissue blood supply and metabolic environment, interfering with thermal balance and causing complications such as inflammation, tissue necrosis, and implant loosening, thus reducing treatment effectiveness and the patient's quality of life. Thermal balance issues caused by foreign bodies in the body after implantation persist throughout the entire bone implant treatment process and are a core factor affecting treatment outcomes and patient recovery, urgently requiring resolution.

[0009] Therefore, there is an urgent need to develop a bone implant that can effectively remove necrotic tissue, provide reliable mechanical support, promote osseointegration, rebuild intraosseous microcirculation, continuously reduce intraosseous pressure, achieve post-implantation thermal balance, and facilitate the drainage of fluid and gas buildup. Such an implant should have controllable production costs, be mass-producible, and have achieved good results in clinical applications. In summary, future research and development should focus on designing and manufacturing an ideal bone implant with a simplified structure, controllable production, convenient operation, and the ability to effectively promote bone tissue repair. This is expected to provide a more reliable and effective solution for treating osteonecrosis and bone defects, bringing better treatment outcomes and quality of life to patients. Utility Model Content

[0010] This invention aims to overcome the shortcomings of existing technologies and provide a bone implant with multiple superior properties. This implant achieves thermal equilibrium, can be combined with bone grafting surgery, and continuously drains fluid and gas buildup after bone necrosis, continuously reducing intraosseous pressure without the need for intraosseous puncture, thus reducing the risk of infection. It also exhibits durable stability, good biocompatibility, and can be perfectly adapted to different populations. Production costs are controllable, and it can be modularly mass-produced, achieving good results in clinical applications.

[0011] A thermally balanced bone graft scaffold, comprising a scaffold shell and a base, characterized in that,

[0012] The bracket housing is located at the head end of the bracket, and the base is located at the tail end of the bracket; the bracket housing and the base are detachably connected.

[0013] The bracket housing has an inner cavity, and the inner cavity has a first opening at the tail end of the bracket housing. The first opening is connected to the head end of the base.

[0014] The base has a multi-purpose chamber at the rear end and a heat convection tube assembly at the front end.

[0015] The multi-purpose chamber is connected to the surface of the base head end through a heat convection pipe assembly; the heat convection pipe assembly connects the inner cavity of the bracket shell to the multi-purpose chamber of the base.

[0016] Furthermore, the heat convection tube assembly includes an upward flow tube and a downward flow tube.

[0017] Furthermore, the upward passage is a heat conduction path from the multi-purpose chamber to the inner cavity. The inlet of the upward passage has a larger diameter, and the outlet of its head has a smaller diameter.

[0018] The downflow pipe provides a heat conduction path from the inner cavity to the multi-purpose chamber. The inlet of the downflow pipe has a larger diameter, while the outlet of the downflow pipe has a smaller diameter.

[0019] Furthermore, the upward and downward conduits can be made of straight pipes, tapered pipes, reducing pipes, hyperboloid pipes, or with enlarged inlets.

[0020] Furthermore, the upward conduit is located in the middle position, while several downward conduits are located around the perimeter.

[0021] Furthermore, there are several upstream and downstream conduits arranged in an array, with the upstream and downstream conduits interleaved.

[0022] Furthermore, the multi-purpose chamber has a second opening at the tail end of the base, which is in the form of an internal hexagon and is used to accommodate operating instruments.

[0023] Furthermore, the second opening is fitted with a tail end sealing component, which has a conveying pipe assembly with openings at both ends of the conveying pipe assembly at the head end face and the tail end face of the tail end sealing component, respectively.

[0024] Furthermore, the head end face of the tail end sealing component forms a concave surface, and a groove is formed on the tail end face of the tail end sealing component, with the external opening of the conveying pipe assembly located within the groove.

[0025] Furthermore, the settling tank is used to connect and operate instruments or external connectors.

[0026] Specifically, the advantages of this utility model are as follows:

[0027] First, it provides a stable support foundation, promoting the bone integration process. The scaffold shell is made of a porous material with interconnected voids (preferably metal 3D printing), possessing excellent mechanical strength and elasticity. In bone grafting surgery, it provides a stable support structure for the transplanted bone, effectively dispersing stress and preventing displacement, deformation, or collapse of the transplanted bone due to unreasonable pressure during healing. This creates a stable mechanical environment for bone tissue growth and fusion, contributing to a higher success rate of bone grafting. The porous structure of the scaffold provides ample space and sites for bone cell adhesion, proliferation, and differentiation, facilitating the ingrowth of new bone tissue and accelerating the integration of the transplanted bone with the surrounding host bone. Furthermore, its interior can be filled with various materials that promote bone repair, such as healthy autologous bone, allogeneic bone, xenogeneic bone, artificial bone, and bioactive materials. These fillers work synergistically with the scaffold to better induce bone regeneration, enhance bone integration, and allow the transplanted bone to fuse more quickly with the patient's own bone, restoring normal bone function.

[0028] Secondly, it achieves overall thermal balance of the stent. Through the built-in heat convection exchange component, it realizes heat convection transfer and heat balance between the head and tail ends of the implant, reduces the high temperature phenomenon at the head end of the affected area, and forms an improved environment for the recovery and growth of the affected area.

[0029] Third, it promotes the drainage of effusion and gas, accelerates bone repair, and slows disease progression. A negative pressure drainage system can be used for minimally invasive, continuous, and repeated drainage of effusion and gas from the lesion. This helps maintain the stability of the femoral head's internal microenvironment, promotes new bone formation and repair, and slows the progression of diseases such as femoral head necrosis. Taking avascular necrosis of the femoral head as an example, timely drainage of effusion and gas produced by necrotic tissue provides space and nutritional support for new bone tissue, helping to improve the femoral head's self-repair ability and increasing the chances of successful hip-preserving treatment.

[0030] Fourth, it continuously releases intraosseous pressure, effectively relieving pain and improving quality of life. Excessive intraosseous pressure is a significant factor in the progression of femoral head-related diseases. This implant releases intraosseous pressure, helping to alleviate pain symptoms and improve quality of life. For example, in patients with early-stage femoral head necrosis, it can relieve hip pain caused by increased pressure within the femoral head, reducing limitations in daily activities, restoring some work and daily living abilities, and significantly improving the patient's quality of life.

[0031] Fifth, it provides storage space and pathways for the input of oxygen and therapeutic drugs and / or nutrients, enabling possible operational forms and plans for external adjunctive treatment of the affected area.

[0032] Sixth, this implant can function stably and long-term, reducing medical costs and improving treatment adherence. Compared to traditional invasive treatments such as repeated punctures and fluid aspirations, and drug injections, it can reduce the number of times patients need to visit the doctor and the treatment costs, thereby improving patient adherence and treatment effectiveness.

[0033] Seventh, from a surgical perspective, the design of this implant fully considers the convenience and safety of the procedure. Its simple implantation method and minimal surgical trauma significantly reduce the burden on the patient's body, enabling faster postoperative recovery. For patients with poor physical condition and limited tolerance, such as elderly patients with femoral head lesions, the advantages of this implant are even more pronounced, allowing more such patients to receive effective treatment and improving the accessibility and safety of treatment.

[0034] Eighth, the implant has excellent biocompatibility. The implant is made from biocompatible materials and optimized to ensure it will not cause strong immune rejection or inflammatory reactions in the body. This reduces complications and the need for subsequent treatments caused by immune reactions, allowing patients to have a better experience during treatment. It also helps improve rehabilitation outcomes and shorten the recovery period. For example, no local redness, swelling, fever, or fluid accumulation will occur after implantation, indicating immune rejection.

[0035] Ninth, from a long-term perspective, it has durable performance and longevity, functioning effectively in the body for an extended period without the need for frequent replacement or adjustment, saving patients subsequent treatment costs and effort. For example, it can function stably for several years or even more than a decade after implantation, eliminating patients' concerns about needing further surgical intervention in the short term.

[0036] Tenth, from a compatibility perspective, this implant can be personalized according to the anatomical structure and lesion condition of different patients' femoral heads, precisely matching the needs of each patient, resulting in more ideal treatment outcomes. For example, it can provide the most suitable implantation plan for patients of different ages, genders, weights, and the degree and extent of lesions.

[0037] Eleventh, multi-system synergy promotes overall rehabilitation. The implant's fluid circulation pathway can be organically combined with postoperative oxygen delivery, degassing, and hyperthermia systems. This innovative combination promotes blood vessel growth within the stent and lesion area, achieving the reconstruction of the oxygen circulation system in the lesion area. By providing the necessary stem cells, oxygen, nutrients, and growth factors to newly formed bone tissue and promptly removing local metabolic waste, a negative pressure drainage system can be used for minimally invasive, continuous, and repeated negative pressure drainage of fluid and gas at the lesion site. This achieves synergistic effects between multiple systems, promoting bone tissue repair and regeneration from multiple dimensions, comprehensively improving the overall treatment effect, and creating more favorable conditions for patient rehabilitation. Attached Figure Description

[0038] Figure 1 3D view of the stent implant;

[0039] Figure 2-3 Schematic diagram of stent implant components;

[0040] Figure 4 3D view of the bracket casing

[0041] Figure 5-6 3D view of the base;

[0042] Figure 7-8 3D view of the tail end sealing component;

[0043] Figure 9-11 Schematic diagram of cross-section of stent implant assembly;

[0044] Figure 12-13 This is a schematic diagram of a porous material scaffold implant.

[0045] In the figure: bracket shell 1, perforated part 11, tail end connection part 12, inner cavity 13, tail end opening 14, positioning and locking recess 15, base 2, receiving cavity 21, upward passage pipe 22, downward passage pipe 23, multi-purpose chamber 24, tail end opening 25, positioning connector 26, tail end sealing part 3, receiving cavity 31, central passage pipe 32, peripheral passage pipe 33, groove 34, concave surface 35, positioning and locking element 4, column 41, head hemispherical protrusion 42. Detailed Implementation

[0046] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0047] Figure 1 , 12 Figure 13 shows the assembled state of the bracket. The bracket includes: a bracket housing 1 and a base 2.

[0048] As a support implant, the stent can be provided for insertion into a surgical site (such as a hole in the bone), and in this specific example, into the femoral head.

[0049] It should be noted that the inner side of the supporting implant within the bone is called the head end, and the outer side is called the tail end.

[0050] The support housing 1 includes a porous portion 11 at the head end and a connecting portion 12 at the tail end. The porous portion 11 can be a porous material with interconnected voids, made by 3D metal printing. The connecting portion 12 is provided at the tail end of the porous portion 11.

[0051] The connecting part of the bracket housing 1 has a tail end opening 14, which communicates with the internal cavity of the bracket housing 1.

[0052] The internal filling material can be inserted into the internal cavity of the bracket housing 11 through the tail opening 14.

[0053] The support housing 1 is cup-shaped and forms a longitudinally extending inner cavity 13. The porous portion 11 has a cylindrical outer wall and a cylindrical inner wall, the cylindrical inner wall defining the inner cavity 13, and is made of a porous material. The relatively elastic properties of the porous material allow the support housing 1 to undergo minute deformations.

[0054] The outer shell 1 and inner cavity 13 of the support can be filled with the following materials, such as healthy autologous bone, allogeneic bone, xenogeneic bone, artificial bone, bioactive materials, etc., to promote the repair of surrounding bones.

[0055] The filler can also be attached to the porous material of the scaffold shell, that is, the filler in the cavity, the filler on the porous material of the scaffold, and the autologous bone around the bone hole are completely fused together.

[0056] Autologous bone can be selected from bone tissue material drilled during the procedure. It can be applied through backfilling to avoid intraoperative loss and can help with bone repair.

[0057] The artificial bone induction material can be selected from one or more of the following: artificial bone synthesized from collagen + sodium alginate + nano hydroxyapatite, artificial bone synthesized from collagen + nano hydroxyapatite, hydroxyapatite (HA), tricalcium phosphate (TCP), and bidirectional calcium phosphate (BCP).

[0058] Bioactive materials are used, such as platelet-rich plasma (PRP).

[0059] The aforementioned filler can be granular and is filled into the inner cavity 13 of the stent using an instrument. The instrument is operated to apply a clamping force to compact the filler.

[0060] The filler can also be processed into a gel form and injected into the inner cavity 13 via a syringe, after which it solidifies.

[0061] After the filler is compressed or solidified in the inner cavity 13, it forms sufficient mechanical strength. The porous material is elastic, and under the action of elastic force generated by the slight deformation, it can ensure that the stent shell 1 will tightly wrap and press the internal filler. Through the covering effect of the stent shell 1, a complete implant is formed.

[0062] Figure 4 As shown, the tail opening 14 of the connecting part of the bracket housing 1 also serves as a positioning and mounting component, and is positioned and installed with the base 2.

[0063] The inner wall of the tail opening 14 is threaded, which can be screwed onto the base 2.

[0064] The support further includes a base 2, which is preferably made of a solid material.

[0065] The outer surface of the base 2 may be provided with threads or a rough surface to increase the friction between the base and the bone during implantation, thereby facilitating stronger adhesion of the scaffold body to the bone.

[0066] The bottom surface of the base 2 is designed with recesses or grooves for connecting with external instruments for surgical operations.

[0067] Figure 5 As shown, a positioning connector 26 is provided at the head end of the base 2, and the positioning mounting part of the connecting part 12 is connected to the positioning connector 26 at the head end of the base 2.

[0068] The positioning connector 26 is a cylinder extending axially at the head end of the base. The outer surface of the positioning connector 26 is threaded to mate with the inner wall thread of the positioning mounting part of the connecting part 12.

[0069] The positioning mounting part of the connecting part 12 and the positioning connecting part 26 at the head end of the base 2 can also adopt a tapered thread. The tapered threads of both can be kept consistent, and the connection can be more stable when tightening.

[0070] Figure 4-6 As shown, to further improve connection stability, positioning and locking recesses 15 are also machined on the inner wall of the tail opening 14. The positioning and locking recesses 15 are several recesses formed on the inner wall, and they are hemispherical in shape. The positioning and locking recesses 15 cooperate with the positioning and locking elements 4 on the base, providing positioning and locking when the bracket housing 1 and the base 2 are threaded together. There are three positioning and locking recesses, which are evenly arranged circumferentially.

[0071] Adaptively, several receiving cavities 21 are also provided around the positioning connector 26 at the head end of the base 2. The receiving cavities 21 are used to place the positioning locking element 4. They cooperate with the positioning locking recess 15 of the positioning mounting part of the connecting part 12. Preferably, the receiving cavities 21 can be arranged in three recesses evenly around the circumference.

[0072] The positioning and locking element 4 includes a column 41 with an internal elastomer and a hemispherical protrusion 42 at the head. Under external pressure, the hemispherical protrusion 42 compresses the internal elastomer. The positioning and locking element 4 is placed in the receiving cavity 21. When the bracket housing is threadedly connected to the base, during the rotational tightening process, the hemispherical protrusion 42 is pressed against the inner wall of the tail opening 14. When the bracket housing rotates to the predetermined position, the hemispherical protrusion 42 pops out and enters the recess 15 on the inner wall of the tail opening 14 to form a positioning and tightening effect, thereby positioning and tightening the threaded connection between the bracket housing and the base.

[0073] The stent shell and base are connected in a detachable manner. The opening at the rear end of the stent shell serves as a positioning and mounting component, threadedly engaging with the positioning connector at the front end of the base. This not only enables quick and accurate installation and removal, facilitating clinical operation and postoperative maintenance, but also ensures the stability of the implant within the body. This detachable connection and positioning mechanism represents a significant innovation in the field of bone implants. Compared to traditional single connection methods, it better adapts to the complex physiological environment of the human body, improving the overall performance of the implant.

[0074] Figure 9-11 As shown, a multi-purpose chamber 24 is also provided in the base 2 at the tail of the positioning connector 26.

[0075] A heat convection tube assembly is arranged inside the positioning connector 26.

[0076] The heat convection tube assembly includes an upward flow tube 22 and a downward flow tube 23.

[0077] The two ends of the upward passage 22 and the downward passage 23 are respectively opened into the head end face of the positioning connector 26 and the multi-purpose chamber 24.

[0078] After the support shell 1 is connected and assembled with the base 2, the inner cavity 13 of the support shell 1 and the multi-purpose chamber 24 can be connected by the upward and downward connecting pipes 22 and 23, thus forming an integrated thermal convection environment space. Due to the biochemical process of the growth and metabolism of the filler, the inner cavity 13 of the support shell 1 has a high temperature. Normal human tissue can achieve heat balance between the inside and outside of the body through fluid circulation. In the early stages of femoral head necrosis, local blood circulation is impaired, and blood stasis leads to inflammatory reactions. The accumulation of inflammatory factors accelerates local metabolism, causing an increase in the internal temperature of the femoral head. Excessively high temperatures affect the normal metabolism of cells within the femoral head. Normal cells, in environments exceeding the suitable temperature range, will have their physiological functions disrupted. High temperatures may inhibit osteoblast activity or even cause cell death, thus hindering new bone formation. This further expands the necrotic area and interferes with the physiological process of femoral head self-repair. Moreover, in the early stages of intraosseous implantation, because removing normal bone tissue cannot remove heat through fluid circulation, local heat accumulation is not conducive to normal tissue growth and may even lead to worsening of the affected area. Maintaining thermal stability in the inner cavity 13 is crucial, requiring the provision of a heat transfer path from the inner cavity 13 to the outside.

[0079] The multi-purpose chamber 24 can be configured as a heat dissipation end communicating with the inner cavity 13. Heat is transferred from the inner cavity 13 to the multi-purpose chamber 24 through a heat convection pipe assembly communicating between the two, and then ultimately conducted from the multi-purpose chamber 24 to the external area of ​​the human body.

[0080] The upward-flow pipe 22 is configured to provide a heat conduction path from the multi-purpose chamber 24 to the inner cavity 13. It is preferably a tapered pipe, with a larger diameter at the inlet and a smaller diameter at the outlet. The tapered pipe generates a pressure difference between the inlet and outlet due to the diameter difference, which ensures the smooth flow of the heat medium from the inlet to the outlet.

[0081] Similarly, the downflow pipe 23 is configured to provide a heat conduction path from the inner cavity 13 to the multi-purpose chamber 24. It is preferably a tapered pipe, with a larger diameter at the inlet and a smaller diameter at the outlet, which ensures smooth flow of the heat medium from the inlet to the outlet through pressure difference.

[0082] The upward passage 22 and the downward passage 23 may contain several, such as Figure 11 As shown,

[0083] An upward-flowing pipe 22 is located at the center of the positioning connector 26, which is used to transfer the low-temperature heat medium in the multi-purpose chamber 24 into the inner cavity 13; several downward-flowing pipes 23 are located around the periphery of the positioning connector 26, which are used to transfer the high-temperature heat medium in the inner cavity 13 into the multi-purpose chamber 24. Thermal balance between the inner cavity 13 and the multi-purpose chamber 24 is achieved by using a heat convection pipe assembly.

[0084] Several downward passage pipes 23 are arranged at intervals around the perimeter of the cavity 21. When the cavity 21 is arranged with three concave holes evenly distributed around its circumference, three downward passage pipes 23 can be evenly distributed at intervals around the cavity.

[0085] In the above implementation scheme, considering the mutual interference between the space occupied by the receiving cavity 21 and the heat convection tube group, a staggered and uniform distribution is adopted.

[0086] In another embodiment (not shown), when the positioning locking element 4 is not used, there is no need to set up the receiving cavity 21, and the heat convection tube assembly can be arranged on the circular cross section of the entire positioning connector 26 as the heat exchange surface.

[0087] Based on thermodynamic principles, an array arrangement can be made on the entire circular cross-section, typically consisting of several equilateral triangular units. Alternatively, an array can be formed by several concentric circles evenly distributed. At each node of the entire array plane, an upward-flowing pipe 22 or a downward-flowing pipe 23 is used, with the upward-flowing pipes 22 and downward-flowing pipes 23 of two adjacent nodes arranged alternately.

[0088] The full-section array arrangement can improve heat exchange efficiency, and the dense array of pipes can help the liquid in the inner cavity 13 to seep into the multi-purpose chamber 24.

[0089] The tapered tube used in the above embodiments is a simplified solution when seeking to reduce product costs.

[0090] If the upward passage pipe 22 and the downward passage pipe 23 are made of equal diameter cylindrical tubes, or if equal diameter cylindrical tubes are made but a local enlargement process is used at the inlet to create a pressure difference, it is sufficient.

[0091] On the other hand, when seeking to improve product performance, further optimization solutions can be adopted.

[0092] If the upward connecting pipe 22 and the downward connecting pipe 23 adopt a more optimized fluid piping type, using a hyperboloid rotating cylinder.

[0093] The hyperboloid rotating cylinder further accelerates the flow of fluid in the pipeline. When the upward pipe 22 and the downward pipe 23 adopt the hyperboloid rotating cylinder type, it can bring excellent heat medium convection effect, and the heat balance efficiency in the inner cavity 13 and the multi-purpose chamber 24 is better.

[0094] Furthermore, the upward passage 22 and the downward passage 23 can adopt any existing feasible passage form, as long as they can provide a thermal convection path from the inner cavity to the multi-purpose chamber.

[0095] like Figure 9-11 As shown, a cylindrical multi-purpose chamber 24 is coaxially arranged within the base 2. The multi-purpose chamber 24 has multiple functions.

[0096] First, the multi-purpose chamber contains a heat transfer fluid, such as gas or liquid. From a thermodynamic point of view, the multi-purpose chamber provides a matching expanded heat volume for the entire bone implant. The matching expanded heat volume can exchange heat with the heat transfer fluid in the inner cavity 13 and achieve overall thermal balance of the entire bone implant from head to tail.

[0097] Secondly, the filling material in the inner cavity 13 of the stent shell 1 will exchange nutrients with the surrounding bone tissue through the porous material, and the bone tissue will grow and fill into the stent. The physiological waste gas and waste fluid generated in this process need to be discharged in time. Since the stent implantation part lacks normal bone tissue, it cannot absorb and excrete waste gas and waste fluid from the human body's physiology. The pressure generated by excessive waste gas and waste fluid will cause physiological discomfort and affect the recovery and growth of bone tissue, so it needs to be discharged in time.

[0098] The internal space of the multi-purpose chamber 24 is connected to the head end cavity 13. Waste gas and waste liquid generated in the head end cavity can enter the multi-purpose chamber through the through-pipe in the heat convection tube assembly. The multi-purpose chamber provides sufficient space to accommodate physiological waste gas and waste liquid in the head end cavity, reducing the impact on bone growth in the head end cavity. The multi-purpose chamber 24 provides temporary storage space for physiological waste. When needed, drainage can be carried out by inserting tubes into the multi-purpose chamber.

[0099] Furthermore, the multi-purpose chamber 24 is further provided with a communication port to the outside of the stent. Through the communication port, externally supplied drugs can be placed into the multi-purpose chamber. The drug action can be delivered to the inner cavity 13 through the convection phenomenon between the inner cavity 13 and the multi-purpose chamber 24, providing drug support for the organic matter in the inner cavity.

[0100] The medication in the multi-use chamber 24 can be placed pre-implanted and / or post-implanted.

[0101] The multi-purpose chamber 24 will be described below.

[0102] The multi-purpose chamber 24 is cylindrical inside the base and has a tail opening 25 at the tail end of the base, which facilitates the processing or cleaning of the internal structure of the base.

[0103] The multi-purpose chamber 24 is also processed to form convection accessories.

[0104] The convection auxiliary device is installed on the inner wall of the multi-purpose chamber. Under the action of the convection auxiliary device, the heat medium (such as gas) in the multi-purpose chamber 24 can be promoted to flow along a specific path to achieve the optimal heat convection exchange effect.

[0105] Fluid guide plates can be used as convection accessories as needed. If a straight fin structure is used, several strip fins can be evenly distributed circumferentially on the inner wall of the multi-purpose chamber. The strip fins are adjacent to each other, and the gap between them is used to form a heat medium fluid path.

[0106] To ensure good guidance of the heat transfer fluid, the strip fins are made at a certain height.

[0107] Its height should be greater than the gap width, preferably 1.5-3 times.

[0108] In other embodiments, the convection accessories can be arranged in a helical pattern, i.e., helical fins are formed axially on the inner wall of the multi-purpose chamber. Similarly, the spacing and height of the helical fins also have a specific proportional relationship, preferably the height being 1.5-3 times the spacing.

[0109] Under the action of the convection auxiliary components, the heat medium in the multi-purpose chamber forms a regular and orderly internal convection field along the length of the multi-purpose chamber, providing optimized internal heat convection exchange.

[0110] Figure 5 As shown, an opening 25 is formed at the tail end of the multi-purpose chamber for processing or cleaning the internal structure of the base. Furthermore, in actual implant application, the tail opening 25 also provides operability; the tail opening 25 has a two-part structure.

[0111] Its outer side is hexagonal, and its inner side has internal threads.

[0112] During implantation, a suitable tool is used in conjunction with the internal hexagon of the tail opening 25 to screw or press the assembled bracket into the bone hole. After implantation, the tail opening 25 needs to be sealed.

[0113] The tail end opening 25 of the multi-purpose chamber has an internal thread on the inside, which is fitted with a tail end sealing piece 3.

[0114] Figure 7-8 As shown, the tail end sealing component 3 is also roughly cylindrical.

[0115] Its head end has an external thread, which connects and engages with the internal thread of the tail end opening 25.

[0116] The tail end face of the tail end sealing component has a recessed groove 34, which is in the form of an internal hexagon.

[0117] When it is necessary to screw the tail end sealing part 3 into the fastener, use an Allen wrench or other operating tool to insert it into the sink 34 and drive the tail end sealing part 3 to rotate and tighten.

[0118] To ensure a stable and secure screw-in of the tail end sealing component 3.

[0119] A positioning and locking recess is also machined into the inner wall of the tail end opening 25 of the multi-purpose chamber. The positioning and locking recess consists of several recesses formed on the inner wall, and is hemispherical in shape. The positioning and locking recess engages with the positioning and locking element 4 on the tail end sealing member, providing positioning and locking when the tail end sealing member 3 is screwed in. There are three positioning and locking recesses, evenly arranged circumferentially.

[0120] The external thread portion of the tail-end sealing member 3 is further provided with several receiving cavities 31, which are used to place the positioning and locking element 4. They cooperate with the positioning and locking recess of the tail-end opening 25 of the multi-purpose chamber. Preferably, the receiving cavities can be arranged in three recesses evenly around the circumference.

[0121] The positioning and locking element 4 at the tail end sealing part and the positioning and locking element 4 at the head end positioning connector 26 of the base 2 adopt the same structure, which improves the interchangeability of instrument parts.

[0122] In another embodiment, the tail end sealing element 3 does not require the connection strength of a threaded fit.

[0123] To provide a simpler and more practical fitting method, the tail end sealing member 3 and the tail end opening 25 of the multi-purpose chamber adopt an insertion fitting method.

[0124] The tail opening 25 of the multi-purpose chamber and the tail sealing part 3 do not need to form internal and external mating threads. They can simply form a mating body with the same profile. Cylindrical or multi-faceted cylinders with the same profile dimensions can be used. To improve the tightness of the fit, a tapered design can be used, that is, a better sealing tightness is achieved after insertion by using a tapered mating surface.

[0125] In the insertion and mating method, to ensure a tight fit between the two parts and prevent them from falling off, a positioning and locking element 4 can be used at the tail end sealing part 3, often employing a positioning and locking recess in the tail end opening 25 of the chamber. When the tail end sealing part 3 is inserted to the predetermined depth, the positioning and locking element 4 enters the positioning and locking recess to achieve positioning and tightening, preventing it from falling off.

[0126] The above is a description of the connection structure and function of the tail-end sealing component 3.

[0127] The other functions of the tail end sealing component 3 will be further described below.

[0128] Multi-purpose chamber 24 needs to continue to transfer heat or exchange gas and liquid with the external environment of the stent.

[0129] A delivery pipe assembly is formed on the tail end sealing member 3, which is similar in structure to the heat convection pipe assembly arranged in the positioning connector 26.

[0130] Figure 7-8 As shown, the conveying pipe assembly includes a central pipe 32 and an outer pipe 33.

[0131] The two ends of the central pipe 32 and the peripheral pipe 33 are respectively opened at the head end face and the tail end face of the tail end sealing member 3.

[0132] The delivery tubing assembly can first serve as an external operating path for liquid aspiration or drug injection.

[0133] The delivery tubing assembly can be connected to the outside of the human body via external fittings. When a large amount of tissue metabolic waste is temporarily stored in the multi-purpose chamber 24, and gas and liquid diffusion, exchange, and absorption cannot be achieved under natural conditions, it needs to be discharged in a timely manner. This waste can be aspirated and discharged through the delivery tubing assembly. Additionally, the delivery tubing assembly can also serve as a pathway for delivering drugs and / or nutrients internally. Adjunctive therapeutic drugs and / or nutrients can be delivered into the multi-purpose chamber 24 via the delivery tubing assembly, temporarily stored within the chamber, and provide therapeutic and / or nutritional benefits to the organic tissues of the inner cavity 13. Ideally, using a delivery needle of a certain length, drug delivery can even be directly administered to the inner cavity 13 via the delivery tubing assembly and the heat convection tubing assembly.

[0134] The delivery pipe assembly includes a central pipe 32 and peripheral pipes 33. With corresponding pipe fittings, an internal and external circulation system can be formed. The tail ends of the central pipe 32 and peripheral pipes 33 open at the bottom of the settling tank 34. The settling tank 34 is hexagonal in shape, allowing the insertion of hexagonal prism-shaped pipe fittings. These fittings also have central and peripheral channels that connect to external equipment. When the delivery pipe assembly, external pipe fittings, and external equipment of the tail-end sealing member 3 are connected, an internal and external circulation system can be formed using the central pipe 32 and peripheral pipes 33. Through external equipment (such as a gas-liquid circulation device), continuous input and output of the internal environment in the multi-purpose chamber 24 and the inner cavity 13 are achieved, thus realizing a circulatory therapeutic effect.

[0135] The central conduit 32 and the peripheral conduit 33 can be straight pipes.

[0136] More preferably, the central conduit 32 and / or the peripheral conduit 33 adopt a better fluid piping type, using a hyperboloid rotating cylinder.

[0137] The hyperboloid rotating cylinder further accelerates the flow of fluid in the pipeline. When the central pipe and / or the peripheral pipe adopt the hyperboloid rotating cylinder type, it can bring excellent heat medium convection effect. The heat transferred from the inner cavity 13 to the multi-purpose chamber 24 can continue to be transferred to the outside through the conveying pipe group on the tail end sealing part 3. This not only achieves thermal balance at the head and tail ends of the support, but also achieves thermal balance between the inside and outside of the support, resulting in better thermal balance efficiency between the inner cavity and the multi-purpose chamber.

[0138] The head end face of the tail-end sealing component 3 forms an arc-shaped concave surface or a conical concave surface. The concave surface 35 can provide a storage area for the temporarily stored gas and liquid inside, and is more conducive to the suction of the temporarily stored gas and liquid during suction output. In addition, the concave surface 35 also provides fluid guidance for the transfer of internal heat to the outside, which is conducive to the balance of heat transfer between the inside and outside of the support.

[0139] The filling material is filled into the cavity 13 of the stent; the filling material can be pre-compressed and pre-cured using instruments;

[0140] It also includes a bone graft compression device used in conjunction with the stent, which can be used to compress the filling material in the inner cavity 13 of the stent.

[0141] The bone graft compression device has a handle and a pressure application part, with one end of the handle fixedly connected to the pressure application part.

[0142] The handle is a long, cylindrical shape for the operator to grip and apply force. The end of the handle serves as an inner cavity for filling and pressurizing.

[0143] When filling the inner cavity 13, the end of the handle is used to pre-compress the filling material.

[0144] After the filler has almost filled the inner cavity 13, it is still necessary to fill to a certain depth inside the positioning and mounting parts, which requires the use of the pressure part. The bottom surface of the pressure part can compress the filler material and make the filler material form a top plane, which can form a complete fit with the top surface of the positioning connector 26 of the base 2.

[0145] In practical applications, a variety of filler materials are available, including autologous bone, allogeneic bone, xenogeneic bone, artificial bone, and bioactive materials. Corresponding filling operation methods have been designed for different fillers, such as instrument filling of granular fillers and syringe injection of colloidal fillers. At the same time, a special bone graft presser is used to apply pressure to ensure filling quality.

[0146] In order to place the implant into a hole in the bone, the components are initially separated from each other.

[0147] First, a corresponding stent lumen filling plan is designed based on the individual patient.

[0148] During the surgical procedure, the femoral head core is drilled to collect the corresponding autologous bone particles; healthy autologous bone, allogeneic bone, xenogeneic bone, artificial bone, bioactive materials, etc. are selected as filling materials.

[0149] The filling material is filled into the cavity and the mesh area; the filling material is pre-compressed and pre-cured using instruments (such as bone graft compactors);

[0150] The stent shell and the base are threaded together, and assembled into a whole implant under the elastic covering of the stent shell 1. After assembly, the stent can be implanted into the cavity formed after the removal of the core decompression lesion in avascular necrosis of the femoral head, providing biomechanical support and promoting the ingrowth of blood vessels and bone tissue.

[0151] The entire implant is inserted into a drilled hole in the bone tissue. The physician uses an internal hexagonal instrument to engage the mating area at the tail of the base 2, such as the tail opening 25 and the countersunk groove 34. The assembled implant is then pressed, screwed, or tapped into the hole. The outer surface of the base 2 may be threaded or roughened, allowing for tight fixation between the base and surrounding tissues through rotation or compression.

[0152] The porous component of the scaffold housing 1 is pressed against the surrounding bone forming the pores, thereby generating initial stability in multiple directions using the scaffold housing 1.

[0153] The implant, situated within the bone cavity, achieves internal thermal equilibrium and guides high temperatures from the scalp to the tail and body surface. The implant's multi-purpose chamber provides sufficient space to accommodate physiological waste gases and fluids within the scalp cavity, minimizing its impact on bone growth.

[0154] When a large amount of tissue metabolic waste is temporarily stored in the multi-use chamber and needs to be discharged promptly, it can be aspirated and discharged through the delivery tubing assembly. Additionally, the delivery tubing assembly can also serve as a pathway for delivering drugs and / or nutrients internally. Oxygen and adjunctive therapeutic drugs and / or nutrients can be delivered into the multi-use chamber 24, temporarily stored within it, and provide therapeutic and / or nutritional benefits to the organic tissues within the lumen 13. Furthermore, it allows for direct drug administration into the lumen 13 using a delivery needle of a certain length, even via the delivery tubing assembly or the heat convection tubing assembly.

[0155] When negative pressure drainage is required, external pipes are connected to the drainage equipment to perform various drainage operations.

[0156] Furthermore, the fluid circulation pathway in the implant can be combined with the postoperative oxygen supply and exhaust system to promote blood vessel growth in the stent and lesion area, realize the reconstruction of the oxygen circulation system in the lesion area, provide the necessary stem cells, oxygen, nutrients, growth factors for new bone tissue, and remove local metabolic waste.

[0157] Furthermore, the components of the scaffold can be fabricated using 3D printing technology, or non-3D printing technologies (such as subtractive manufacturing, vapor deposition, or sintering). The scaffold can be processed into any other shape as needed. This scaffold is a porous titanium alloy scaffold, but the material can also be tantalum, titanium-tantalum alloy, nickel-titanium alloy, pure titanium, cobalt alloy, calcium phosphate, hydroxyapatite, polylactic acid (PLA), lactic acid-glycolic acid copolymer (PLGA), polyacetin (PCL), coral, or bioceramics, etc.

[0158] This invention offers a wide variety of filler options to meet the needs of different patients and clinical treatment scenarios. Healthy autologous bone can be used as a filler, directly selected from bone tissue material drilled during the procedure. Through backfilling, not only can intraoperative bone tissue loss be avoided, but the biological characteristics of autologous bone itself also help accelerate the bone repair process. In addition, allogeneic bone, xenogeneic bone, artificial bone, and various bioactive materials can also be used as filler options. Artificial bone induction materials can be selected from one or more of the following: artificial bone synthesized from collagen + sodium alginate + nano-hydroxyapatite, artificial bone synthesized from collagen + nano-hydroxyapatite, hydroxyapatite (HA), tricalcium phosphate (TCP), and bidirectional calcium phosphate (BCP). These artificial bone materials have good biocompatibility and bone induction properties, providing an effective scaffold and guide for new bone formation. Regarding bioactive materials, platelet-rich plasma (PRP) is rich in various growth factors, which can actively promote cell proliferation, differentiation, and tissue repair, providing strong bioactive support for bone tissue regeneration.

[0159] Corresponding filling methods were designed for different types of fillers. For granular fillers, specially designed instruments are used to fill them into the scaffold cavity. During the filling process, the instruments apply appropriate clamping force to ensure the filler is evenly distributed and compacted within the scaffold cavity, guaranteeing a stable structure and providing a solid foundation for bone growth. For gel-like fillers, a syringe is used to precisely inject them into the cavity. After injection, the filler undergoes a solidification reaction, forming a stable filling structure within the scaffold cavity. Whether granular or gel-like, after compaction or solidification, the filler achieves sufficient mechanical strength within the scaffold cavity, working in conjunction with the elastic scaffold shell to form a complete implant structure. The scaffold shell, with its porous material and elastic properties, tightly encapsulates and continuously compresses the internal filler under the elastic force generated by minute deformations, achieving a balance between strength and toughness, further enhancing the stability and integrity of the implant.

[0160] To ensure the quality and uniformity of the filler material within the stent cavity, a specially designed bone graft compactor was employed. The compactor consists of a handle and a pressure-applying section, which work together to precisely compress the filler material. The handle is designed as a long, cylindrical shape for easy gripping and application of force. During the initial filling stage, the handle can be used to pre-compact the filler material, establishing a certain degree of compaction within the stent cavity. Once the cavity is nearly full, a further depth of filler needs to be inserted into the positioning and mounting components. This is achieved using the pressure-applying section, whose outer surface is designed to precisely match the inner surface of the positioning and mounting components. When the pressure-applying part is inserted into the positioning and mounting component, its bottom surface can apply a uniform and effective clamping force to the filler material, so that the filler material forms a top plane inside the positioning and mounting component. This top plane can form a complete and tight fit with the top surface of the base positioning insert, ensuring the connection stability between the stent shell and the base. It also ensures the uniform distribution and compactness of the filler in the entire stent cavity, laying a solid foundation for the implant to perform optimally in the body.

[0161] Finally, it should be noted that the above description is merely an explanation of this utility model and is not intended to limit it. Although this utility model has been described in detail, those skilled in the art can still modify the foregoing technical solutions or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this utility model should be included within the protection scope of this utility model.

Claims

1. A thermally balanced bone graft scaffold, comprising a scaffold shell and a base, characterized in that, The bracket housing is located at the head end of the bracket, and the base is located at the tail end of the bracket; the bracket housing and the base are detachably connected. The bracket housing has an inner cavity, and the inner cavity has a first opening at the tail end of the bracket housing. The first opening is connected to the head end of the base. The base has a multi-purpose chamber at the rear end and a heat convection tube assembly at the front end. The multi-purpose chamber is connected to the surface of the base head end through a heat convection pipe assembly; the heat convection pipe assembly connects the inner cavity of the bracket shell to the multi-purpose chamber of the base.

2. The thermally balanced bone graft scaffold according to claim 1, characterized in that, The heat convection tube assembly includes an upward flow tube and a downward flow tube.

3. The thermally balanced bone graft scaffold according to claim 2, characterized in that, The upward-flowing pipe is a heat conduction path from the multi-purpose chamber to the inner cavity. The inlet of the upper-flowing pipe has a larger diameter, while the outlet of its head has a smaller diameter. The downflow pipe provides a heat conduction path from the inner cavity to the multi-purpose chamber. The inlet of the downflow pipe has a larger diameter, while the outlet of the downflow pipe has a smaller diameter.

4. The thermally balanced bone graft scaffold according to claim 2, characterized in that, The upward and downward conduits can be made of straight pipes, tapered pipes, reducing pipes, hyperboloid pipes, or with enlarged inlets.

5. The thermally balanced bone graft scaffold according to claim 2, characterized in that, The upward conduit is located in the middle, and several downward conduits are located around the perimeter.

6. The thermally balanced bone graft scaffold according to claim 2, characterized in that, There are several upstream and downstream conduits arranged in an array, and the upstream and downstream conduits are arranged alternately.

7. The thermally balanced bone graft scaffold according to claim 1, characterized in that, The multi-purpose chamber has a second opening at the tail end of the base. The second opening is in the form of an internal hexagon and is used to accommodate operating instruments.

8. The thermally balanced bone graft scaffold according to claim 7, characterized in that, The second opening is used to install the tail end sealing component, which has a conveying pipe assembly with openings at both ends on the head and tail end faces of the tail end sealing component.

9. The thermally balanced bone graft scaffold according to claim 8, characterized in that, The head end face of the tail end sealing component forms a concave surface, and a groove is formed on the tail end face of the tail end sealing component. The external opening of the conveying pipe assembly is located in the groove.

10. The thermally balanced bone graft scaffold according to claim 9, characterized in that, The settling tank is used to connect and operate instruments or external connectors.

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