Anti-spinning press-fit built-in artificial limb connector
By adopting a built-in prosthetic connector designed with a press-fit fixation and anti-rotation fixation mechanism, the long-term complications and infection risk problems of built-in prosthetic connectors in the prior art are solved, and the built-in prosthetic connector for early stable fixation in amputation patients is realized, which improves limb function and quality of life.
Patent Information
- Application Number
- CN202421006575.X
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-05-10
- Publication Date
- 2025-03-07
- Estimated Expiration
- 2034-05-10
AI Technical Summary
The existing built-in prosthetic connectors have long-term complications during use, such as host bone resorption and mechanical loosening, and have a high risk of infection, which affects the limb function and quality of life of amputated patients.
The built-in prosthetic connector designed with a press-fit fixation and anti-rotation fixation mechanism includes a medullary needle, connector body, prosthetic connector head and anti-rotation lock nail. The marrow cavity of the stump bone is implanted through a medullary needle, and the anti-rotation lock nail is used to prevent rotation, enhancing the connection stability.
The built-in prosthetic connector for early stable and fixed in amputation patients is realized, reducing the risk of long-term mechanical loosening and infection, and improving limb function and quality of life.
Smart Images
Figure CN222566041U_ABST
Abstract
Description
Technical Field
[0001] The utility model belongs to the technical field of medical devices, and in particular relates to an internal prosthetic connector which adopts a press-fit fixation and an anti-rotation fixation mechanism to achieve early stable fixation of patients with limb amputations. Background Art
[0002] Amputation is the removal of a limb that has no vitality or is seriously life-threatening due to local diseases. Common causes of amputation include peripheral vascular disease, trauma, burns, electrical injuries and frostbite, infection and malignant tumors. The most common cause of amputation in developed countries in Europe and the United States is diabetic foot, while in my country and other developing countries, it is limb damage caused by various injuries. According to the data of the second national survey of people with disabilities in my country in 2006, the total number of people with disabilities in my country is 82.96 million, of which 24.12 million are physically disabled and 2.26 million are amputees, accounting for 8% of the number of people with physical disabilities. How to restore the ability of the above-mentioned people to take care of themselves and even their normal working ability is an objective demand of my country's economic and social development in the field of medical and health care.
[0003] The function of human limbs is to perform various movements under the cooperation of the nervous system and other systems. During the movement, the contraction of skeletal muscles is the driving force of movement, the bones play a lever role, and the joints are the hubs of movement. The compensatory function after wearing a prosthesis is achieved by exerting the function of the residual limb and utilizing the characteristics of the prosthetic structure. The muscle strength of the residual limb is the driving force of movement, and the residual limb plays a lever role in controlling the movement of the prosthesis. The physiology of healthy people's limb movement and the compensatory function of amputees after wearing prostheses are both achieved in the form of movement. The movement of the prosthesis is completed through the control of the residual limb and the coordinated movements of the two. The residual limb is the active part of the movement and is a movement organ different from the healthy limb. The requirements for prosthetic assembly on the residual limb are as follows: ① The residual limb should have an appropriate length and moderate soft tissue coverage to ensure sufficient leverage and good muscle control. Any prosthesis must be attached to the residual limb to function. If the residual limb is too short, the leverage of the prosthesis will be weakened and the prosthesis will be difficult to function; if the residual limb is too long, the joint part of the prosthesis will be affected by the need for A certain space plays a role, so it will also affect the prosthesis after assembly Limb function. The residual limb length is related to the choice of amputation plane. ② The remaining joint should retain its original physiological function as much as possible, without contracture and deformity. ③ There should be no tenderness, bone spurs, or neuroma at the stump, so sufficient muscle should be used to cover the stump during surgery to reduce the stimulation of the bone end on the skin. ④ The stump should have good skin conditions, be healthy and smooth, have few scar adhesions, and no sinus ulcers. Therefore, the prosthetic fitting that matches the stump well and can play a satisfactory compensatory function is crucial to the quality of life and limb function of amputees after surgery.
[0004] With the continuous improvement of my country's economic development level, the country's attention to people with functional disabilities after amputation is also increasing. How to improve the function of the limb stumps of amputees and improve the labor capacity of the above-mentioned people so that they can return to society is a new issue posed by my country's economic and social development to clinical doctors. At the same time, surgical operations and prosthetic assembly in many hospitals in my country are still out of touch. Doctors no longer ask about it after the operation, so that many patients do not even have basic limb bandages after amputation. When they go to configure prostheses, they need to be re-bandaged, which wastes time, increases the economic burden on patients, and affects the function of the stumps. How to solve the problem of postoperative limb stump functional reconstruction in amputees in an integrated manner is also a realistic clinical problem that needs to be solved urgently.
[0005] At present, the main way to reconstruct the limb stump function of amputees in my country is still to use traditional cavity-type prostheses, but there are many problems with it: the walking speed of the prosthesis cannot change naturally and arbitrarily with the changes in the walking speed of the amputee, and cannot meet the needs of the amputee to change the speed within a larger range of walking speed to improve walking flexibility. In this case, the amputee can only walk at a speed that matches the fixed swing speed of the prosthesis. Too fast or too slow will cause the symmetry of the healthy leg and the prosthesis to be seriously damaged, making the amputee more likely to feel tired. At the same time, the poor air permeability of the cavity will cause the amputation stump to be soaked in sweat for a long time, leading to skin ulcers and other problems. In order to solve the problems and shortcomings of cavity-type prostheses in practical applications, in 1990, Swedish orthopedic surgeons used internal prostheses to reconstruct the limb stump function of a patient who underwent amputation surgery due to trauma. After that, a variety of built-in prosthetic connectors have flourished, including OPRA (Osseointegrated prosthesis for the rehabilitation of amputees, Sweden), OPL (Osseointegrated Prosthetic Limb, UK) and Compress (USA). Although the styles of built-in prosthetic connectors in different countries are different, the overall design concept is the same. The connector medullary pin is used to press fit and rivet with the patient's residual bone, and the connector is connected to the prosthesis percutaneously. This design can improve the coordination of the patient's walking speed and the swing speed of the prosthesis, thereby improving the functional status of the limb stump of amputees. However, there are currently no reports on the clinical application of such built-in prostheses in my country. Although built-in prostheses are widely used in the functional reconstruction of the limb stumps of amputees in Europe and the United States, there are many problems with built-in prostheses reported internationally: First, due to the stress shielding of the built-in prosthetic medullary pin and the host bone riveting point, long-term complications such as host bone absorption and mechanical loosening occur, which affect the long-term life of the built-in prosthesis. Second, because the connector needs to be connected to the prosthesis through the skin from deep inside the limb stump, some soft tissue and skin are in direct contact with the metal, increasing the risk of infection. How to reduce and avoid the occurrence of the above complications is crucial to improving the limb function and quality of life of amputees. Utility Model Content
[0006] The utility model aims to solve at least one of the technical problems existing in the prior art. To this end, the utility model provides an internal prosthetic connector that uses a press-fit fixation and an anti-rotation fixation mechanism to achieve early stable fixation of patients with quadruple amputations.
[0007] In order to achieve the above purpose, the utility model adopts the following technical solutions:
[0008] A rotation-proof press-fit internal prosthesis connector comprises: a medullary pin, the upper end of which is suitable for being implanted into the medullary cavity of a stump bone by press-fitting and being tightly connected thereto, and the upper end of the medullary pin is provided with at least two nail holes, and the lower end of the medullary pin forms a tapered joint; a connector body, which is a special-shaped structure with a thin upper end and a thick lower end, and the upper end of the connector body forms a tapered connection groove, and the tapered joint of the medullary pin and the tapered connection groove of the connector body are assembled by tapered connection; a prosthesis connector, which is tightly connected to the lower end of the connector body, and the prosthesis connector is suitable for being connected to an external prosthesis by a conversion joint; and anti-rotation locking nails, wherein at least two of the anti-rotation locking nails pass through the nail holes of the stump bone and the medullary pin and form a dynamic cross-locking to prevent the prosthesis connector from rotating.
[0009] Preferably, it also includes a guide, which has an L-shaped structure and includes a guide connector and a guide rod, one end of the guide connector is fixedly connected to the prosthesis connector by a locking screw, and the guide rod is integrally connected to the other end of the guide connector and extends axially along the medullary needle, and at least two locking nail guide holes are provided on the guide rod.
[0010] Preferably, it also includes an extramedullary sleeve, which is a tubular structure with one end open and the other end closed, and the interior of the extramedullary sleeve defines a bone stump fixing cavity for accommodating the stump bone, and the extramedullary sleeve can be sleeved on the outside of the stump bone through its open end and tightly connected thereto, and a through tapered hole is formed at the closed end of the extramedullary sleeve, and the extramedullary sleeve is sleeved on the outside of the intramedullary needle through the tapered hole and taperedly abuts against the upper end of the connector body.
[0011] Preferably, the outer medullary sleeve adopts a three-pronged design, that is, the wall of the outer medullary sleeve is designed to be three fixed arms distributed at intervals along the circumferential direction, one end of the three fixed arms is connected to the closed end of the outer medullary sleeve, and the other ends of the three fixed arms extend axially to jointly enclose a bone stump fixing cavity.
[0012] Preferably, a plurality of muscle suture holes are processed on the connector body at intervals along the circumferential direction.
[0013] Preferably, a porous metal trabecular structure with a pore size of 400-600 μm and completely interconnected is prepared on the outer surface of the medullary needle and the connector body by 3D printing technology, with a porosity of more than 80% and a pore layer thickness of 2 mm.
[0014] The utility model adopts the above technical solution, which has the following advantages:
[0015] 1. After assembling the medullary needle and the connector body, the utility model presses the medullary needle into the medullary cavity of the amputation stump bone by means of a press-fit method, thereby tightly fixing the built-in prosthetic connector on the stump bone, thereby realizing the integration and stable fixation of the prosthetic connector and the stump bone.
[0016] 2. After the medullary needle is driven into the medullary cavity of the stump bone, the utility model can ensure the rapid and accurate placement of at least two anti-rotation locking screws during the operation to form a dynamic cross-locking with the aid of a matching guide, and increase the rotational stability of the prosthetic connector under the condition of medullary needle press-fitting, which not only facilitates the patient to walk and bear weight in the early stage after surgery, but also reduces the occurrence of long-term mechanical loosening and infection. In order to avoid rotational stress after walking and bearing weight in the early stage, medullary needles fixed by press-fitting are usually not recommended for walking and bearing weight in the early stage after implantation, but the design of adding anti-rotation locking screws can increase early stability and have the mechanical advantage of being able to walk and bear weight in the early stage.
[0017] 3. The connection between the medullary needle and the connector body in the utility model adopts a tapered connection design. During the operation, the corresponding medullary needle thickness and connector body model can be determined according to the size of the medullary cavity and the bone volume of the patient's amputated stump, which is convenient for dealing with different stump sizes in clinical practice. The patient can replace the prosthetic connector at will according to the actual situation, solving the problem that the limb stump of amputated patients cannot achieve integrated functional reconstruction after surgery.
[0018] 4. The utility model uses 3D printing technology to process the surface of the medullary pin into a metal pore structure. After the amputation operation, the medullary pin is pressed into the medullary cavity. Under the huge pressure-fitting effect, the surface of the medullary pin can effectively ensure that the cancellous bone in the medullary cavity grows into the metal pores on the surface of the medullary pin, so that the host bone and the prosthetic connector are integrated, thereby avoiding the frequent long-term loosening and infection of the existing built-in prosthetic connector.
[0019] 5. The utility model uses 3D printing technology to process the surface of the connector body into a metal pore structure. When the muscles of the amputated stump are fixed to the connector body, soft tissues such as muscles can grow into the metal pores, thereby forming a bioactive layer with rich blood supply on the metal surface of the prosthetic connector, which can reduce the risk of implant infection and reduce the stimulation of the prosthetic connector to the skin tissue deep in the skin, thereby solving the problem of wound complications of existing built-in prosthetic connectors.
[0020] In summary, the utility model can be widely used in patients who undergo amputation for different reasons, and can realize the integrated connection between the built-in prosthetic connector and the amputation stump, making it convenient for amputee patients to replace different more comfortable prostheses according to their own needs. BRIEF DESCRIPTION OF THE DRAWINGS
[0021] By reading the detailed description of the preferred embodiment below, various other advantages and benefits will become clear to those of ordinary skill in the art. The accompanying drawings are only used for the purpose of illustrating the preferred embodiment and are not considered to be limiting of the present invention. The same reference numerals are used throughout the accompanying drawings to represent the same components. In the accompanying drawings:
[0022] Figure 1 This is a structural schematic diagram of an anti-rotation press-fitting internal prosthesis connector provided by a preferred embodiment of the utility model;
[0023] Figure 2 This is a diagram showing the use state of the anti-rotation press-fitting internal prosthesis connector provided by this embodiment of the utility model;
[0024] Figure 3 It is a structural schematic diagram of an anti-rotation press-fitting internal prosthesis connector provided by another preferred embodiment of the utility model.
[0025] The reference numerals in the figures are as follows:
[0026] 1-medullary needle; 2-connector body; 3-prosthesis connector; 4-anti-rotation screw; 5-guide; 6-extramedullary sleeve;
[0027] 10-residual bone; 11-cone joint; 21-cone joint groove; 22-muscle suture hole; 51-guide connector; 52-guide rod; 53-locking screw guide hole. DETAILED DESCRIPTION
[0028] In order to make the purpose, technical solution and advantages of the utility model clearer, the specific embodiments of the utility model are further described below in conjunction with the accompanying drawings. Although the exemplary embodiments of the utility model are shown in the accompanying drawings, it should be understood that the utility model can be implemented in various forms and should not be limited by the embodiments described here. On the contrary, these embodiments are provided to enable a more thorough understanding of the utility model and to fully convey the scope of the utility model to those skilled in the art.
[0029] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present invention.
[0030] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the present utility model, the meaning of "plurality" is more than two, unless otherwise clearly and specifically defined.
[0031] In the present invention, unless otherwise expressly specified or limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or a formed connection. One; can be Mechanical connection or electrical connection; it can be directly connected or through an intermediate medium. Connected may be the internal connection of two elements or the interaction relationship between two elements. For those skilled in the art, the specific meanings of the above terms in the present utility model can be understood according to specific circumstances.
[0032] In the present utility model, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may mean that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Moreover, a first feature being "above", "above" or "above" a second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. A first feature being "below", "below" or "below" a second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.
[0033] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the utility model. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, without contradiction.
[0034] The utility model provides an anti-rotation press-fit built-in prosthesis connector, comprising: a medullary pin, the upper end of which is suitable for being implanted into the medullary cavity of the stump bone by press-fitting and being tightly connected thereto, and the upper end of the medullary pin is provided with at least two nail holes, and the lower end of the medullary pin forms a conical joint; a connector body, which is a special-shaped structure with a thin upper end and a thick lower end, and a conical connection groove is formed at the upper end of the connector body, and the conical joint of the medullary pin and the conical connection groove of the connector body are assembled by conical connection; a prosthesis connector, which is tightly connected to the lower end of the connector body, and the prosthesis connector is suitable for being connected to an external prosthesis through a conversion joint; and anti-rotation locking nails, wherein at least two anti-rotation locking nails pass through the nail holes of the stump bone and the medullary pin and form a dynamic cross-locking to prevent the prosthesis connector from rotating. The utility model can be widely used in patients who undergo amputation for different reasons, and realizes the integrated connection between the built-in prosthesis connector and the amputation stump, so as to facilitate amputee patients to replace different more comfortable prostheses according to their own needs.
[0035] The anti-rotation press-fitting internal prosthesis connector provided by a preferred embodiment of the utility model is described in detail below in conjunction with the accompanying drawings.
[0036] See also Figure 1 , Figure 2 The utility model provides an anti-rotation press-fit internal prosthesis connector in a preferred embodiment, comprising a medullary needle 1, a connector body 2, a prosthesis connector 3 and an anti-rotation locking nail 4. The upper end of the medullary needle 1 is suitable for being implanted into the medullary cavity of the stump bone 10 by press-fitting and being tightly connected thereto, and at least two nail holes are provided at the upper end of the medullary needle 1, and a conical joint 11 is formed at the lower end of the medullary needle 1; the connector body 2 is a special-shaped structure with a thin upper end and a thick lower end, and a conical connection groove 21 is formed at the upper end of the connector body 2, and the conical joint 11 of the medullary needle 1 is assembled with the conical connection groove 21 of the connector body 2 by a conical connection; the prosthesis connector 3 is tightly connected to the lower end of the connector body 2, and the prosthesis connector 3 is suitable for being connected to an external prosthesis through a conversion joint; at least two anti-rotation locking nails 4 pass through the nail holes of the stump bone 10 and the medullary needle 1 and form a dynamic cross-locking to prevent the prosthesis connector from rotating.
[0037] In the above embodiment, preferably, a guide 5 is further included, which is in an L-shaped structure, including a guide connector 51 and a guide rod 52. One end of the guide connector 51 is fixedly connected to the prosthesis connector 3 through a locking screw, and the guide rod 52 is integrally connected to the other end of the guide connector 51 and extends along the axial direction of the medullary needle 1. At least two locking screw guide holes 53 are formed on the guide rod 52. Therefore, by using the guide 5, the cortex is drilled with a drill bit in the direction determined by the locking screw guide hole 53, so that the anti-rotation screw 4 can be screwed in quickly and accurately during the operation.
[0038] In the above embodiments, preferably, please refer to Figure 3, and also includes an outer medullary sleeve 6, which is a tubular structure with an open end and a closed end. The inner part of the outer medullary sleeve 6 defines a bone stump fixing cavity for accommodating the stump bone. The outer medullary sleeve 6 can be sleeved on the outside of the stump bone through its open end and tightly connected thereto. A through tapered hole is opened at the closed end of the outer medullary sleeve 6. The outer medullary sleeve 6 is sleeved on the outside of the medullary needle 1 through the tapered hole and taper-connected to the upper end of the connector body 2.
[0039] In the above embodiment, preferably, please continue to refer to Figure 3 The outer medullary sleeve 6 adopts a three-pronged design, that is, the wall of the outer medullary sleeve 6 is designed to be three fixed arms 61 distributed at intervals along the circumferential direction, one end of the three fixed arms 61 is connected to the closed end of the outer medullary sleeve 6, and the other end of the three fixed arms 61 extends axially to jointly surround the bone stump fixing cavity. Through the above-mentioned arrangement, the outer medullary sleeve 6 has a certain expansion space when the outer medullary sleeve 6 is driven in due to its own three-pronged tubular structure, which facilitates the simultaneous driving of the medullary needle 1 and the outer medullary sleeve 6.
[0040] In the above embodiments, preferably, please refer to Figure 1 A plurality of muscle suture holes 22 are processed at circumferential intervals on the connector body 2, so that the muscles of the amputation stump can be passed through the muscle suture holes and tightly wrapped around the outside of the connector body 2 by sutures, ensuring that the connector body 2 has abundant muscle coverage and does not directly contact the skin, thereby reducing the risk of prosthesis infection and increasing the power of the stump prosthesis.
[0041] In the above embodiment, preferably, a porous metal trabecular structure with a pore size of 400-600 μm and completely interconnected is prepared on the outer surface of the medullary needle 1 and the connector body 2 using 3D printing technology, and the porosity is above 80%, and the pore layer thickness is 2 mm, thereby providing space for the growth of new bone tissue, allowing the new bone tissue to creep into the porous structure, and ultimately integrating the medullary needle 1 and the connector body 2 on the stump bone, greatly increasing the long-term stability and service life of the prosthetic connector.
[0042] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them; although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein by equivalents; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present application, and they should all be included in the scope of the claims and specification of the present application. In particular, as long as there is no structural conflict, the various technical features mentioned in the various embodiments can be combined in any way. The present application is not limited to the specific embodiments disclosed herein, but includes all technical solutions that fall within the scope of the claims.
Claims
1. An anti-rotation press-fit internal prosthesis connector, characterized in that: include: A medullary needle, the upper end of which is suitable for being implanted into the medullary cavity of the stump bone by press-fitting and being firmly connected thereto, and the upper end of the medullary needle is provided with at least two nail holes, and the lower end of the medullary needle forms a cone joint; The connector body is a special-shaped structure with a thin upper end and a thick lower end. A conical connection groove is formed at the upper end of the connector body. The conical joint of the medullary needle is assembled with the conical connection groove of the connector body by a conical connection method. A prosthesis connector, which is fixedly connected to the lower end of the connector body, and is suitable for connecting to an external prosthesis through a conversion joint; Anti-rotation locking nails, at least two of which pass through the stump bone and the nail holes of the medullary pin and form a dynamic cross-locking to prevent the prosthetic connector from rotating.
2. The anti-rotation press-fit internal prosthesis connector according to claim 1, characterized in that: It also includes a guide, which has an L-shaped structure and includes a guide connector and a guide rod. One end of the guide connector is fixedly connected to the prosthesis connector by a locking screw, and the guide rod is integrally connected to the other end of the guide connector and extends axially along the medullary needle. At least two locking nail guide holes are provided on the guide rod.
3. The anti-rotation press-fit internal prosthesis connector according to claim 1, characterized in that: It also includes an extramedullary sleeve, which is a tubular structure with one end open and the other end closed. The interior of the extramedullary sleeve defines a bone stump fixing cavity for accommodating the stump bone. The extramedullary sleeve can be sleeved on the outside of the stump bone through its open end and tightly connected thereto. A through tapered hole is provided at the closed end of the extramedullary sleeve. The extramedullary sleeve is sleeved on the outside of the intramedullary needle through the tapered hole and tapered against the upper end of the connector body.
4. The anti-rotation press-fitting internal prosthesis connector according to claim 3, characterized in that: The extramedullary sleeve adopts a three-pronged design, that is, the wall of the extramedullary sleeve is designed as three fixing arms distributed at intervals along the circumferential direction, one end of the three fixing arms is connected to the closed end of the extramedullary sleeve, and the other ends of the three fixing arms extend axially to jointly enclose a bone stump fixing cavity.
5. The anti-rotation press-fitting internal prosthesis connector according to claim 1, characterized in that: A plurality of muscle suture holes are processed at intervals along the circumferential direction on the connector body.
6. The anti-rotation press-fitting internal prosthesis connector according to claim 1, characterized in that: A fully interconnected porous metal trabecular structure with a pore size of 400-600 μm is prepared on the outer surface of the medullary needle and the connector body by using 3D printing technology, with a porosity of more than 80% and a pore layer thickness of 2 mm.