Intramedullary cannula and prosthesis having the same

Abstract

The present invention provides an intramedullary cannula and a prosthesis having the same, wherein the intramedullary cannula comprises: a tube body, the tube body is a mesh tube woven from material threads, the material threads are made of memory material, and the inner hole of the tube body can accommodate the prosthesis. The technical solution of the present invention can effectively solve the problem of poor stability of prosthesis fixation in the prior art.

Description

Technical Field

[0001] The present invention relates to the technical field of prosthesis installation, and in particular to an intramedullary sleeve and a prosthesis having the same. Background Art

[0002] At present, artificial joint replacement has been widely used in clinical treatment and is one of the standard surgeries for treating joint diseases. Artificial joint replacement has the advantages of relieving pain, improving joint function, and restoring joint stability and limb function. However, due to problems with the material of the joint prosthesis itself and the replacement technology, complications such as loosening and dislocation may occur after surgery. When the above complications occur, revision is required.

[0003] In the prior art, when the replaced prosthesis is revised, due to problems such as osteolysis and stress shielding, a large range of bone defects will be caused when the prosthesis and bone cement are removed, which brings inconvenience to the re-implantation of the prosthesis. For example, when the prosthesis and bone cement need to be removed during the femoral revision, auxiliary operations such as greater trochanter extension osteotomy and femoral fenestration are required to achieve the removal of the prosthesis and bone cement, which will cause a large range of bone defects, making it difficult to fix the prosthesis and poor stability after fixation. Summary of the invention

[0004] The main purpose of the present invention is to provide an intramedullary cannula and a prosthesis having the same, so as to solve the problem of poor stability of prosthesis fixation in the prior art.

[0005] To achieve the above objective, according to one aspect of the present invention, an intramedullary cannula is provided, comprising: a tube body, the tube body being a mesh tube woven from material threads made of memory material, and the inner hole of the tube body being capable of accommodating a prosthesis.

[0006] Furthermore, there are multiple material threads, and each of the material threads on the cross section of the tube body is not perpendicular to each other.

[0007] Furthermore, the intramedullary cannula also includes: an outer sleeve, which is woven from material threads and wraps the surface of the tube body, and the inner hole of the outer sleeve forms a receiving hole for accommodating the prosthesis.

[0008] Furthermore, the surface of the tube body is provided with a plurality of free ends of material threads, and the free ends of the respective material threads are connected to the outer sleeve.

[0009] Furthermore, a first notch is provided on the side wall of the tube body and passes through the end surfaces of both ends of the tube body, and a second notch corresponding to the first notch is provided on the outer sleeve, and the second notch passes through the end surfaces of both ends of the outer sleeve.

[0010] Furthermore, the diameter of the inner hole of the outer sleeve is between 3 mm and 35 mm, and / or the diameter of the outer side wall of the outer sleeve is between 5 mm and 40 mm, and / or the length of the outer sleeve is between 20 mm and 500 mm.

[0011] Furthermore, the taper of the outer side wall of the outer sleeve is between 1° and 15°.

[0012] Furthermore, the memory material is a nickel-titanium material or a cobalt-chromium material.

[0013] Furthermore, the intramedullary cannula is printed by a 3D printer.

[0014] According to another aspect of the present invention, a prosthesis is provided, comprising: a prosthesis body; an intramedullary cannula, wherein the intramedullary cannula is the intramedullary cannula mentioned above, and the proximal end of the prosthesis body is inserted into the inner hole of the tube body of the intramedullary cannula.

[0015] By applying the technical solution of the present invention, the tube body is made of a memory material, and the tube body has a contracted state and a supported state. When the tube body is in the contracted state, its volume is small, which is convenient for placing it into the medullary cavity. When the tube body is in the supported state, its volume increases. During renovation, the tube body in the contracted state is first placed into the medullary cavity, and then the state of the tube body is changed to the supported state. The tube body in the supported state can abut against the inner wall of the medullary cavity and be fixed inside the medullary cavity, and then the prosthesis is fixed in the tube body to complete the fixation of the prosthesis. The above structure can enhance the strength of the medullary cavity, facilitate the fixation of the prosthesis, and also improve the stability of the prosthesis after implantation. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] The drawings constituting a part of the present application are used to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the drawings:

[0017] Figure 1 A schematic longitudinal section structure diagram of an embodiment of an intramedullary cannula according to the present invention after being installed in the intramedullary cannula is shown;

[0018] Figure 2 Shows Figure 1 A schematic side view of the intramedullary cannula;

[0019] Figure 3 Shows Figure 1 A schematic diagram of the cross-sectional structure of the intramedullary cannula; and

[0020] Figure 4 Shows Figure 3 A schematic cross-sectional structure diagram of the tubular body of the intramedullary cannula; and

[0021] Figure 5 Shows Figure 1 Schematic diagram of the structure after superposition of the intramedullary cannula.

[0022] The above drawings include the following reference numerals:

[0023] 1. Material wire; 2. Free end; 3. Medullary cavity; 10. Tube body; 11. First notch; 20. Outer sleeve; 21. Receiving hole; 22. Second notch; 23. Inner sleeve; 24. Outer sleeve; 25. End sleeve; 40. Inner sleeve of medullary cavity. DETAILED DESCRIPTION

[0024] It should be noted that, in the absence of conflict, the embodiments and features in the embodiments of the present application can be combined with each other. The present invention will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0025] like Figures 1 to 4 As shown, the intramedullary cannula of this embodiment includes: a tube body 10, which is a mesh tube woven from material wires 1, and the material wires 1 are made of memory material. The inner hole of the tube body 10 can accommodate a prosthesis.

[0026] Using the technical solution of this embodiment, the tube body 10 is made of a memory material, and the tube body 10 has a contracted state and a supported state. When the tube body 10 is in the contracted state, its volume is small, which is convenient for being placed inside the medullary cavity 3. When the tube body 10 is in the supported state, its volume increases. During renovation, the tube body 10 in the contracted state is first placed inside the medullary cavity 3, and then the state of the tube body 10 is changed to the supported state. The tube body 10 in the supported state can abut against the inner wall of the medullary cavity 3 and be fixed inside the medullary cavity 3, and then the prosthesis is fixed in the tube body 10 to complete the fixation of the prosthesis. The above structure can strengthen the strength of the medullary cavity 3, facilitate the fixation of the prosthesis, and also improve the stability of the prosthesis after implantation.

[0027] It should be noted that the intramedullary cannula needs to be soaked in ice saline before implantation to make it in a contracted state, and then placed in the medullary cannula 3. After a few minutes, the intramedullary cannula will expand into a supporting state, close to the inner side of the medullary cannula 3, and then the prosthesis will be implanted therein to complete the revision.

[0028] like Figures 2 to 4 As shown, in this embodiment, there are multiple material filaments 1, and each material filament 1 is not perpendicular to each other on the cross section of the tube body 10. In the above structure, if each material filament 1 on the cross section of the tube body 10 is perpendicular to each other, the contraction ability of the tube body 10 in the radial direction is poor, making it difficult to implant the tube body 10 into the medullary cavity 3. If each material filament 1 is not perpendicular to each other, the contraction ability of the tube body 10 in the radial direction can be improved, thereby facilitating the implantation of the tube body 10.

[0029] It should be noted that if Figure 4 As shown, the tube body 10 has a plurality of cross sections, and each material wire 1 on each of the cross sections is not perpendicular to each other.

[0030] like Figures 1 to 4As shown, in this embodiment, the intramedullary cannula further includes: an outer sleeve 20, the outer sleeve 20 is woven from material filaments 1 and wraps the surface of the tube body 10, and the inner hole of the outer sleeve 20 forms a receiving hole 21 for accommodating the prosthesis. In the above structure, since there are multiple free ends 2 of material filaments 1 on the surface of the tube body 10, if the free ends 2 of the material filaments 1 directly abut against the medullary cavity 3, the material filaments 1 are subjected to greater stress and are prone to breakage. Broken material filaments 1 will form metal debris, which will have an adverse effect on the patient's health after entering the body. Providing the outer sleeve 20 can reduce the probability of the free ends 2 of the material filaments 1 contacting the medullary cavity 3, that is, reduce the probability of broken wires, thereby protecting the material filaments 1.

[0031] It should be noted that if Figures 2 to 4 As shown, in this example, the outer sleeve 20 includes an inner sleeve 23, an outer sleeve 24, and end sleeves 25 located at both ends of the inner sleeve 23 and the outer sleeve 24. The inner sleeve 23 can be connected to the free end of the inner side of the material wire 1, the outer sleeve 24 can be connected to the free end of the outer side of the material wire 1, and the end sleeve 25 can be connected to the free end of the material wire 1 located at the end of the outer sleeve. The above structure enables the free ends of the material wire 1 at various locations to be connected to the outer sleeve 20, thereby further reducing the probability of the material wire 1 breaking.

[0032] like Figures 2 to 4 As shown, in this embodiment, the surface of the tube body 10 has a plurality of free ends 2 of the material wires 1, and the free ends 2 of the material wires 1 are connected to the outer sleeve 20. The above structure can strengthen the strength of the free ends 2 of the material wires 1 by connecting the free ends 2 to the outer sleeve 20, avoid stress concentration, and thus prevent the material wires 1 from breaking due to excessive stress, thereby protecting the material wires 1.

[0033] like Figures 2 to 4 As shown, in this embodiment, the side wall of the tube body 10 is provided with a first notch 11 penetrating the end faces of both ends of the tube body 10, and the outer sleeve 20 is provided with a second notch 22 corresponding to the first notch 11, and the second notch 22 penetrating the end faces of both ends of the outer sleeve 20. In the above structure, the first notch can increase the deformation of the tube body 10, and the deformation amount can reach 20%. Accordingly, the second notch provided on the outer sleeve 20 can protect the tube body 10, thereby preventing the material wire 1 from breaking due to excessive stress.

[0034] In this embodiment, the diameter of the inner hole of the outer sleeve 20 is between 3 mm and 35 mm. A suitable type of intramedullary cannula can be selected according to the actual size of the prosthesis.

[0035] In this embodiment, the diameter of the outer wall of the outer sleeve 20 is between 5 mm and 40 mm. A suitable type of intramedullary cannula can be selected according to the actual inner diameter of the medullary cavity 3 of the patient.

[0036] In this embodiment, the length of the outer sleeve 20 is between 20 mm and 500 mm. A suitable type of intramedullary cannula can be selected according to the actual length of the patient's medullary cannula 3. Figure 5 As shown, when the medullary cavity 3 is long, the tubular body 10 can be arranged into multiple sections, so as to facilitate the implantation of the tubular body 10 .

[0037] like Figure 1 As shown, in this embodiment, the taper of the outer wall of the outer sleeve 20 is between 1° and 15°. The above structure enables the intramedullary cannula to adapt to the shape of the medullary cavity 3, so that the intramedullary cannula can be connected to the medullary cavity 3 more stably.

[0038] In this embodiment, the memory material is a nickel-titanium material or a cobalt-chromium material. In the above structure, the nickel-titanium material and the cobalt-chromium material have the advantages of wear resistance and corrosion resistance in addition to the function of memory shape. Therefore, the above materials can not only facilitate the fixation of the prosthesis, but also prolong the period of re-renovation or eliminate the need for re-renovation, thereby improving the stability of the prosthesis after implantation.

[0039] In this embodiment, the intramedullary cannula is printed by a 3D printer. The above structure can improve the processing accuracy of the intramedullary cannula.

[0040] The present invention also provides a prosthesis. An embodiment of the prosthesis of the present invention includes: a prosthesis body and an intramedullary sleeve 40, wherein the intramedullary sleeve 40 is the above-mentioned intramedullary sleeve, and the proximal end of the prosthesis body is inserted into the inner hole of the tube body 10 of the intramedullary sleeve 40. Since the intramedullary sleeve 40 has the advantage of being able to improve the stability of prosthesis fixation, the prosthesis having it also has the above-mentioned advantages. It should be noted that in this embodiment, the prosthesis body is a femoral stem prosthesis. In other embodiments, the prosthesis body can also be other prostheses such as a humeral stem.

[0041] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. An intramedullary cannula, characterized in that: include: A tube body (10), the tube body (10) being a mesh tube woven from material threads (1), the material threads (1) being made of memory material, and the inner hole of the tube body (10) being capable of accommodating a prosthesis; An outer sleeve (20), the outer sleeve (20) being woven from material threads (1) and wrapping around the surface of the tube body (10), the inner hole of the outer sleeve (20) forming a receiving hole (21) for receiving the prosthesis; The surface of the tube body (10) is provided with a plurality of free ends (2) of the material threads (1), and each free end (2) of the material threads (1) is connected to the outer sleeve (20); The memory material is a nickel-titanium material or a cobalt-chromium material.

2. The intramedullary cannula according to claim 1, characterized in that: The material threads (1) are multiple in number, and the material threads (1) on the cross section of the tube body (10) are not perpendicular to each other.

3. The intramedullary cannula according to claim 1, characterized in that: The side wall of the tube body (10) is provided with a first notch (11) penetrating the end surfaces of both ends of the tube body (10), and the outer sleeve (20) is provided with a second notch (22) corresponding to the first notch (11), and the second notch (22) penetrating the end surfaces of both ends of the outer sleeve (20).

4. The intramedullary cannula according to claim 1, characterized in that: The diameter of the inner hole of the outer sleeve (20) is between 3 mm and 35 mm, and / or the diameter of the outer wall of the outer sleeve (20) is between 5 mm and 40 mm, and / or the length of the outer sleeve (20) is between 20 mm and 500 mm.

5. The intramedullary cannula according to claim 1, characterized in that: The taper of the outer side wall of the outer sleeve (20) is between 1° and 15°.

6. The intramedullary cannula according to claim 1, characterized in that: The intramedullary cavity sleeve is printed by a 3D printer.

7. A prosthesis comprising: Prosthesis body; An intramedullary cannula (40), characterized in that the intramedullary cannula (40) is the intramedullary cannula described in any one of claims 1 to 6, and the proximal end of the prosthesis body is inserted into the inner hole of the tube body (10) of the intramedullary cannula (40).

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