CN110584842A - Extendable prosthesis - Google Patents

Abstract

The present invention provides an extendable prosthesis, in which a first prosthesis, a second prosthesis and a deformation structure are arranged, wherein the first prosthesis has an accommodation chamber, and the second prosthesis is connected to the first prosthesis. Body connection, the second prosthesis is movably set relative to the first prosthesis, the deformation structure is arranged in the accommodation cavity, one end of the deformation structure cooperates with the second prosthesis, the deformation structure is made of magnetic memory alloy, and the deformation structure can be placed on the outside Deformation occurs under the action of the magnetic field, and the deformed structure drives the second prosthesis to move away from the first prosthesis under the condition of deformation, so as to extend the total length of the prosthesis. Since the deformable structure is made of a magnetically controlled shape memory alloy, the deformable structure can be deformed by applying a magnetic field externally, thereby extending the prosthesis. In this way, after the prosthesis is implanted, the prosthesis can be extended only by applying a suitable magnetic field from the outside, so no traumatic surgery is required.

Description

extendable prosthesis

technical field

The invention relates to the technical field of medical devices, in particular to an extendable prosthesis.

Background technique

There are more than 10,000 primary osteosarcoma cases in China every year. Osteosarcoma accounts for 10% of primary bone tumors and 20% of primary malignant tumors. The annual incidence is 1-3 per 1 million people, and 75% of the patients are 10-30 years old. It seriously affects the body and mind of young adults. healthy malignancy.

The concept of limb salvage surgery has evolved and matured over the past 25 years. Limb salvage surgery mainly includes the complete resection of the involved bone tumor and the reconstruction of the bone defect. In the past two to three decades, bone tumor diagnosis and treatment centers in the United States and Europe have used various reconstruction techniques. Reconstruction of limbs. With the analysis of follow-up results of different reconstruction methods in recent years, it is found that artificial metal prosthesis reconstruction has achieved good mid-term and long-term follow-up results. The advantages of artificial prosthesis reconstruction include: durable internal fixation, and immediate postoperative stability Good, good short-term and long-term functional prognosis, good range of motion after surgery.

In adolescents, the growth of the distal femoral and proximal tibial epiphyseal plates (sites of bony growth) accounts for 70% of the total lower extremity ascending developmental length. Resection of the inferior femoral plate will result in a loss of approximately 1.6 cm per year in the affected limb. For this reason, knee resection in very young patients (less than 10 years) with bone tumors is bound to cause severe limb disparity. For children with bone tumors, as the survival time prolongs, complications such as limb length disequilibrium and claudication caused by prosthetic reconstruction after tumor segment resection are increasing day by day. Children have a great deal of bone growth capacity, and any metal prosthesis will eventually require revision as the child grows.

At present, about 10% of patients with primary bone tumors face the problem of limb length disequilibrium after limb salvage surgery. Extendable prosthesis can better solve this problem, but because the currently widely used extendable prosthesis requires surgery every time it is extended, a certain length of incision is made to expose the extension screw, and the mechanical drive device is used to extend the prosthesis. The length of the extension is limited (the blood vessels and nerves cannot tolerate stretching), and multiple operations increase the chance of infection and tissue scarring. Therefore, the invasive and extendable prosthesis currently used by doctors greatly increases the number of operations and the chance of postoperative complications for pediatric patients. This frequent operation process will last for ten years or even longer, causing considerable pain and economic burden to patients.

Contents of the invention

The present invention provides an extendable prosthesis to solve the problem in the prior art that the extendable prosthesis needs trauma-generating operations to be extended.

In order to solve the above problems, the present invention provides an extendable prosthesis, including: a first prosthesis, the first prosthesis has a receiving cavity; a second prosthesis, the second prosthesis is connected with the first prosthesis, and the second prosthesis The body is movably arranged relative to the first prosthesis; the deformation structure is arranged in the receiving cavity, and one end of the deformation structure cooperates with the second prosthesis. The deformation structure is made of magnetic memory alloy, and the deformation structure can be generated under the action of an external magnetic field Deformation, the deformation structure drives the second prosthesis to move away from the first prosthesis under the condition of deformation, so as to extend the total length of the extensible prosthesis.

Further, the deformation structure is a stretchable structure, and the deformation structure is elongated under the action of an external magnetic field to drive the movement of the second prosthesis.

Further, the extendable prosthesis also includes: a first anti-retreat structure, at least a part of the first anti-retreat structure is movably arranged, both the first prosthesis and the second prosthesis cooperate with the first anti-retreat structure, and the first anti-retreat structure The retreat structure is used to prevent the second prosthesis from moving toward the first prosthesis, so as to prevent the second prosthesis from retreating after the movement is completed.

Further, the first anti-retreat structure includes: a plurality of first anti-retreat grooves, and the plurality of first anti-retreat grooves are arranged on one of the first prosthesis and the second prosthesis; Any one of the plurality of first anti-recession slots is clamped, and the first clamping part is movably arranged on the other of the first prosthesis and the second prosthesis; the second prosthesis moves away from the first prosthesis In the case of moving in one direction, the first clamping part avoids a plurality of first anti-retreat grooves so that the second prosthesis moves in one direction; after the movement of the second prosthesis is completed, the first clamping part snaps into the corresponding first anti-retreat slot to prevent the second prosthesis from receding.

Further, the deformation structure is a helical first spring structure; or, the deformation structure includes a plurality of sequentially connected stretchable layers, and each stretchable layer can be stretched under the action of an external magnetic field.

Further, the deformation structure includes a plurality of stretchable layers, and the stretchable layer includes: two connecting plates arranged at intervals and a support plate arranged at intervals between the two connecting plates, each support plate is arranged obliquely relative to the connecting plate, and the outer Under the action of the magnetic field, the inclination angles of the supporting plates all change in the same direction, so as to change the distance between the two connecting plates.

Further, ribs are provided on one of the inner wall of the first prosthesis and the outer wall of the second prosthesis, and the ribs extend along the moving direction of the second prosthesis; the inner wall of the first prosthesis and the outer wall of the second prosthesis The other one is provided with a chute, the chute extends along the moving direction of the second prosthesis, and the ribs are slidably arranged in the chute.

Further, the first prosthesis includes a lower sleeve and an upper sleeve connected to each other, the deformation structure is arranged in the lower sleeve, the second prosthesis is passed through the upper sleeve and the lower sleeve, and the upper sleeve and the second dummy A sealing structure is provided between the bodies.

Further, one end of the upper sleeve facing the lower sleeve has a first limiting surface, and the second prosthesis includes: an intramedullary rod, the intramedullary rod passes through the upper sleeve, and the sealing structure is located between the upper sleeve and the intramedullary rod space; the top post, the top post is connected with the intramedullary rod, at least a part of the top post is located in the lower sleeve, the top post has a second limit surface, the deformation structure cooperates with the top post to drive the top post and the intramedullary rod to move, the first The second limit surface cooperates with the first limit surface to limit the moving distance of the intramedullary rod.

Further, the extendable prosthesis is a femoral prosthesis, and the first prosthesis also includes: a femoral condyle, and the lower sleeve is connected to the femoral condyle.

Further, the extendable prosthesis also includes: a second anti-regression structure, at least a part of the second anti-regression structure is movably arranged, and both the intramedullary rod and the push post cooperate with the second anti-regression structure, and the second anti-regression structure is used for It is used to prevent the top column from moving in the direction close to the deformed structure.

Further, the second anti-regression structure includes: a plurality of second anti-regression grooves, and the plurality of second anti-regression grooves are arranged on one of the intramedullary rod and the push post; Any one of the two anti-recession grooves is clamped, and the second clamping part is movably arranged on the other one of the intramedullary rod and the push post.

Applying the technical solution of the present invention, a first prosthesis, a second prosthesis and a deformation structure are provided in the extendable prosthesis, wherein the first prosthesis has an accommodation cavity, the second prosthesis is connected with the first prosthesis, and the second prosthesis is connected to the first prosthesis. The second prosthesis is movably arranged relative to the first prosthesis. The deformation structure is arranged in the accommodation cavity. One end of the deformation structure cooperates with the second prosthesis. The deformation structure is made of magnetic memory alloy. Deformation occurs, and the deformation structure drives the second prosthesis to move away from the first prosthesis under the condition of deformation, so as to extend the total length of the extensible prosthesis. Since the deformable structure is made of a magnetically controlled shape memory alloy, the deformable structure can be deformed by applying a magnetic field externally, thereby extending the prosthesis. In this way, after the prosthesis is implanted, the prosthesis can be extended only by applying a suitable magnetic field from the outside, so no traumatic surgery is required. In this way, the child will not suffer from the pain of two or more operations, and the number of extensions per unit time (such as within one year) can be increased according to the growth of the legs of the child, and the length of each extension can be reduced accordingly, so that The child is more likely to adapt to the length of the legs and balance problems after each extension.

Description of drawings

The accompanying drawings constituting a part of the present application are used to provide a further understanding of the present invention, and the schematic embodiments and descriptions of the present invention are used to explain the present invention, and do not constitute an improper limitation of the present invention. In the attached picture:

FIG. 1 shows a schematic structural view of an extendable prosthesis provided by an embodiment of the present invention;

Figure 2 shows a cross-sectional view of the extendable prosthesis in Figure 1;

Fig. 3 shows a partial enlarged view of Fig. 2 at position A;

Figure 4 shows a schematic diagram of the first anti-retreat groove in Figure 3;

Fig. 5 shows a schematic diagram of the first clamping part in Fig. 3;

Figure 6 shows a schematic diagram of the sealing structure in Figure 2;

Fig. 7 shows the schematic diagram of top column and deformation structure in Fig. 2;

Fig. 8 shows a schematic view of the extendable prosthesis in Fig. 1 adopting another deformed structure;

Figure 9 shows an enlarged view of the deformed structure in Figure 8;

Figure 10 shows a schematic structural view of the upper sleeve in Figure 1;

Fig. 11 shows a schematic structural view of the intramedullary rod in Fig. 1;

Figure 12 shows a partial enlarged view of Figure 2 at position B;

Figure 13 shows a schematic diagram of the second anti-retreat groove in Figure 12;

FIG. 14 shows a schematic diagram of the second locking part in FIG. 12 .

Wherein, the above-mentioned accompanying drawings include the following reference signs:

10. First prosthesis; 11. Lower sleeve; 12. Upper sleeve; 13. Femoral condyle; 20. Second prosthesis; 21. Intramedullary rod; 22. Apex; 23. Rod body; 24. Boss ;30. Deformation structure; 31. Scalable layer; 32. Connecting plate; 33. Support plate; 41. The first anti-retreat groove; 42. The first clamping part; 43. The first spring; 44. The first clamping block ; 51, convex rib; 52, chute; 61, sealing sleeve; 62, sealing ring; 71, plate body; 72, limit tooth; 81, second anti-retreat groove; The second spring; 84, the second block.

Detailed ways

The following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the drawings in the embodiments of the present invention. Apparently, the described embodiments are only some of the embodiments of the present invention, but not all of them. The following description of at least one exemplary embodiment is merely illustrative in nature and in no way taken as limiting the invention, its application or uses. Based on the embodiments of the present invention, all other embodiments obtained by persons of ordinary skill in the art without creative efforts fall within the protection scope of the present invention.

As shown in the accompanying drawings, the embodiment of the present invention provides an extendable prosthesis, including: a first prosthesis 10, the first prosthesis 10 has a receiving chamber; a second prosthesis 20, the second prosthesis 20 is connected with The first prosthesis 10 is connected, and the second prosthesis 20 is movably arranged relative to the first prosthesis 10; the deformation structure 30 is arranged in the receiving cavity, and one end of the deformation structure 30 cooperates with the second prosthesis 20, and the deformation structure 30 is formed by Made of magnetic memory alloy, the deformable structure 30 can be deformed under the action of an external magnetic field. When deformed, the deformable structure 30 drives the second prosthesis 20 to move away from the first prosthesis 10 to extend the prosthesis. The total length of the prosthesis.

Applying the technical solution of the present invention, a first prosthesis 10, a second prosthesis 20 and a deformation structure 30 are arranged in the extendable prosthesis, wherein the first prosthesis 10 has an accommodation cavity, and the second prosthesis 20 is connected to the first prosthesis. The prosthesis 10 is connected, the second prosthesis 20 is movably arranged relative to the first prosthesis 10, the deformation structure 30 is arranged in the accommodation cavity, and one end of the deformation structure 30 cooperates with the second prosthesis 20, and the deformation structure 30 is made of magnetic memory alloy made, the deformable structure 30 can be deformed under the action of an external magnetic field, and the deformable structure 30 drives the second prosthesis 20 to move away from the first prosthesis 10 under the condition of deformation, so as to extend the length of the prosthesis. total length. Since the deformable structure 30 is made of a magnetically controlled shape memory alloy, the deformable structure 30 can be deformed by applying an external magnetic field, thereby extending the prosthesis. In this way, after the prosthesis is implanted, the prosthesis can be extended only by applying a suitable magnetic field from the outside, so no traumatic surgery is required. In this way, the child will not suffer from the pain of two or more operations, and the number of extensions per unit time (such as within one year) can be increased according to the growth of the legs of the child, and the length of each extension can be reduced accordingly, so that The child is more likely to adapt to the length of the legs and balance problems after each extension. During the adjustment, the moving distance of the second prosthesis 20 is precisely controlled by controlling the strength and time of the magnetic field applied from the outside, so as to control and extend the total length of the prosthesis.

In this embodiment, the deformation structure 30 is a stretchable structure, and the deformation structure 30 is stretched under the action of an external magnetic field to drive the movement of the second prosthesis 20 . In this way, the second prosthesis 20 can be driven to move through the elongation of the deformation structure 30 .

In order to improve reliability, in this embodiment, the extendable prosthesis further includes: a first anti-retreat structure, at least a part of the first anti-retreat structure is movably arranged, and both the first prosthesis 10 and the second prosthesis 20 are connected to The first anti-retreat structure cooperates, and the first anti-retreat structure is used to prevent the second prosthesis 20 from moving toward the first prosthesis 10, so as to prevent the second prosthesis 20 from retreating after the movement is completed. The first anti-retraction structure realizes that the second prosthesis 20 can only move in one direction away from the first prosthesis 10 , but cannot move in a direction close to the first prosthesis 10 , thereby avoiding contraction of the prosthesis after being extended.

Specifically, the first anti-retreat structure includes: a plurality of first anti-retreat grooves 41, and the plurality of first anti-retreat grooves 41 are arranged on one of the first prosthesis 10 and the second prosthesis 20; 42, used to engage with any one of the multiple first anti-retreat grooves 41, the first engaging portion 42 is movably arranged on the other of the first prosthesis 10 and the second prosthesis 20; the second When the prosthesis 20 moves away from the first prosthesis 10, the first engaging part 42 avoids a plurality of first anti-retreat grooves 41 so that the second prosthesis 20 moves in one direction; the movement of the second prosthesis 20 is completed Afterwards, the first engaging portion 42 is engaged in the corresponding first anti-retreat groove 41 to prevent the second prosthesis 20 from retreating. In this way, the unidirectional movement of the second prosthesis 20 can be realized through the cooperation of the first engaging portion 42 and the plurality of first anti-retreat grooves 41 .

Optionally, a plurality of first anti-recession grooves 41 are provided on the outer wall of the second prosthesis 20, and the first engaging part 42 is provided on the inner wall of the first prosthesis 10, and there are multiple first engaging parts 42, to improve reliability. The first clamping part 42 is provided telescopically or the first clamping part 42 is rotatably provided, and the first clamping part 42 includes a first spring 43 and a first clamping block arranged in the groove of the first prosthesis 10 44. The first block 44 can extend out or retract into the groove. The first block 44 has a first limiting plane and a first guiding slope, and the first anti-retreat groove 41 has a second limiting plane and a second guiding slope, wherein the first limiting plane and the second limiting plane Cooperate to prevent retreat when the second prosthesis 20 is subjected to external axial pressure, and the first guide slope cooperates with the second guide slope to push the first clamping block 44 when the second prosthesis 20 moves in the direction of elongation retract into the groove.

In this embodiment, the deformation structure 30 is a helical first spring structure; or, the deformation structure 30 includes a plurality of sequentially connected stretchable layers 31 , and each stretchable layer 31 can be stretched under the action of an external magnetic field.

As shown in Figures 8 and 9, the deformation structure 30 includes a plurality of stretchable layers 31, and the stretchable layer 31 includes: two connecting plates 32 arranged at intervals and a support plate 33 arranged at intervals between the two connecting plates 32, Each support plate 33 is arranged obliquely relative to the connection plate 32, and under the action of an external magnetic field, the inclination angle of each support plate 33 changes in the same direction to change the distance between the two connection plates 32, thereby realizing the stretchable layer 31 elongation, two adjacent stretchable layers 31 share a connecting plate 32 . Through the above arrangement, a larger stretching range of the stretchable layer 31 can be realized, thereby realizing a larger stretching range of the deformable structure 30, which is convenient for adjusting the total length of the prosthesis.

In this embodiment, one of the inner wall of the first prosthesis 10 and the outer wall of the second prosthesis 20 is provided with a rib 51, and the rib 51 extends along the moving direction of the second prosthesis 20; the first prosthesis 10 The other one of the inner wall of the second prosthesis 20 and the outer wall of the second prosthesis 20 is provided with a chute 52 , the chute 52 extends along the moving direction of the second prosthesis 20 , and the rib 51 is slidably disposed in the chute 52 . Through the above arrangement, the movement of the second prosthesis 20 can be guided and the relative rotation of the first prosthesis 10 and the second prosthesis 20 in the circumferential direction can be avoided. The protruding rib 51 is arranged on the inner wall of the upper sleeve 12 , and the slide groove 52 is arranged on the outer wall of the intramedullary rod 21 .

In this embodiment, the first prosthesis 10 includes a lower sleeve 11 and an upper sleeve 12 connected to each other, the deformation structure 30 is arranged in the lower sleeve 11, and the second prosthesis 20 is passed through the upper sleeve 12 and the lower sleeve. In the cylinder 11 , a sealing structure is provided between the upper sleeve 12 and the second prosthesis 20 . By setting the upper sleeve 12 and the lower sleeve 11, the manufacture and assembly of each component is facilitated. A good sealing effect can be achieved by providing a sealing structure, preventing body fluids and the like from entering the first prosthesis 10 and affecting normal use. Optionally, the upper sleeve 12 and the lower sleeve 11 are screwed or welded, and the end of the upper sleeve 12 has a limit step for matching with the end surface of the lower sleeve 11 .

In this embodiment, one end of the upper sleeve 12 facing the lower sleeve 11 has a first limiting surface, and the second prosthesis 20 includes: an intramedullary rod 21 passing through the upper sleeve 12, a sealing structure Located between the upper sleeve 12 and the intramedullary rod 21; the push post 22, the push post 22 is connected to the intramedullary rod 21, at least a part of the push post 22 is located in the lower sleeve 11, and the push post 22 has a second limit surface, The deformation structure 30 cooperates with the push post 22 to drive the push post 22 and the intramedullary rod 21 to move, and the second limiting surface cooperates with the first limiting surface to limit the moving distance of the intramedullary rod 21 .

Optionally, the push post 22 includes a rod body 23 and a boss 24 arranged at one end of the rod body 23, the rod body 23 is penetrated in the intramedullary rod 21, the boss 24 is arranged in the lower sleeve 11, and the second limit surface is located on the boss. On the platform 24 , the deformation structure 30 abuts against the boss 24 . A limiting step is provided on the outer wall of the intramedullary rod 21 for limiting cooperation with the end of the upper sleeve 12 to limit the length of the intramedullary rod 21 penetrating into the upper sleeve 12 .

Optionally, the sealing structure includes: a sealing sleeve 61 sleeved on the intramedullary rod 21, a limit step is provided on the sealing sleeve 61 to limitly cooperate with the end of the upper sleeve 12, and a plurality of sealing rings 62 are located on the upper sleeve 12. In the annular groove of the inner wall of the sleeve 12, to improve the sealing effect.

The extendable prosthesis can be used for implantation in tibia, radius, ulna and other bones. In this embodiment, the extendable prosthesis is a femoral prosthesis, and the first prosthesis 10 further includes: a femoral condyle 13 , and the lower sleeve 11 is connected to the femoral condyle 13 . This extendable prosthesis can then be used for implantation in the residual femur.

Optionally, the lower sleeve 11 includes a sequentially connected cylinder body, a limit post and a positioning post, the positioning post is a tapered structure, the diameter of the positioning post is smaller than the diameter of the stop post, and the stop post and the positioning post pass through the In the femoral condyle 13, to realize positioning and limit.

Optionally, the first prosthesis 10 also includes a load-bearing structure, which is arranged at the bottom of the cavity of the lower sleeve 11. The load-bearing structure includes a plate body 71 and limit teeth 72 arranged on the plate body 71. The deformation structure 30 and the plate body The body 71 abuts, and the limit tooth 72 is inserted into the bottom wall of the cavity.

In order to further improve the reliability, the extendable prosthesis also includes: a second anti-regression structure, at least a part of the second anti-regression structure is movably arranged, and both the intramedullary rod 21 and the push post 22 cooperate with the second anti-regression structure, and the second anti-regression structure The second anti-retraction structure is used to prevent the top column 22 from moving towards the deformation structure 30 . In this way, after the movement of the second prosthesis 20 is completed and the deformation structure 30 is retracted, the apical post 22 can be prevented from moving toward the deformation structure 30 , thereby preventing the axial gap between the intramedullary rod 21 and the apical post 22 .

Further, the second anti-regression structure includes: a plurality of second anti-regression grooves 81, and the plurality of second anti-regression grooves 81 are arranged on one of the intramedullary rod 21 and the top post 22; In order to engage with any one of the multiple second anti-regression grooves 81 , the second engaging portion 82 is movably disposed on the other one of the intramedullary rod 21 and the abutment post 22 . Through the above setting, the axial position of the intramedullary rod 21 and the push post 22 can be realized. Moreover, when the intramedullary rod 21 and the push post 22 need to be disassembled, by applying a pulling force away from each other to the two, the second engaging part 82 can avoid a plurality of second anti-recession grooves 81 so that the intramedullary rod 21 and the top post 22 can be disengaged.

Optionally, a plurality of second anti-recession grooves 81 are provided on the outer wall of the top column 22, and the second locking part 82 is provided on the inner wall of the intramedullary rod 21, and there are multiple second locking parts 82 to improve reliability. sex. The second locking part 82 is telescopically arranged or the second locking part 82 is rotatably arranged, and the second locking part 82 includes a second spring 83 and a second locking block 84 arranged in the groove of the intramedullary rod 21 , the second block 84 can extend out or retract into the groove. The second block 84 has a first limiting plane and a first guiding slope, and the second anti-retreat groove 81 has a second limiting plane and a second guiding slope, wherein the first limiting plane and the second limiting plane Cooperate, the first guide slope cooperates with the second guide slope to push the second block 84 back into the groove when the intramedullary rod 21 and the abutment post 22 need to be separated.

This scheme is designed in accordance with the shape requirements of the human femoral condyle, which is thick at the distal end and thin at the proximal end. The upper and lower sleeves are made separately and then welded into one. It has a sealing effect to prevent body fluids from entering the interior of the prosthesis and causing corrosion damage to the internal material. The end of the prosthesis is made of PEEK plastic. PEEK has excellent biocompatibility and wear resistance, which prevents the metal at the end from wearing under bending stress.

Applying the technical solution of the present invention, a first prosthesis 10, a second prosthesis 20 and a deformation structure 30 are arranged in the extendable prosthesis, wherein the first prosthesis 10 has an accommodation cavity, and the second prosthesis 20 is connected to the first prosthesis. The prosthesis 10 is connected, the second prosthesis 20 is movably arranged relative to the first prosthesis 10, the deformation structure 30 is arranged in the accommodation cavity, and one end of the deformation structure 30 cooperates with the second prosthesis 20, and the deformation structure 30 is made of magnetic memory alloy made, the deformable structure 30 can be deformed under the action of an external magnetic field, and the deformable structure 30 drives the second prosthesis 20 to move away from the first prosthesis 10 under the condition of deformation, so as to extend the length of the prosthesis. total length. Since the deformable structure 30 is made of a magnetically controlled shape memory alloy, the deformable structure 30 can be deformed by applying an external magnetic field, thereby extending the prosthesis. In this way, after the prosthesis is implanted, the prosthesis can be extended only by applying a suitable magnetic field from the outside, so no traumatic surgery is required. In this way, the child will not suffer from the pain of two or more operations, and the number of extensions per unit time (such as within one year) can be increased according to the growth of the legs of the child, and the length of each extension can be reduced accordingly, so that The child is more likely to adapt to the length of the legs and balance problems after each extension. During the adjustment, the moving distance of the second prosthesis 20 is precisely controlled by controlling the strength and time of the magnetic field applied from the outside, so as to control and extend the total length of the prosthesis.

In order to facilitate the understanding of this scheme, the magnetic memory alloy is properly explained below:

After the traditional shape memory alloy is plastically deformed in the martensitic state, it will automatically return to the state of the parent phase if it is heated above the Af temperature; if it is cooled again below the Mf temperature, it will automatically recover to the original plastically deformed or martensitic shape. And it has a much larger strain than other driving materials, but the strain must be obtained by changing the temperature of the alloy, so its response speed is very slow. Traditional shape memory alloys, such as TiNi-based, Fe-based, Cu-based alloys, etc., have large reversible recovery strain and large recovery force, but because they are driven by the temperature field, their response frequency is low (about 1Hz ). In recent years, a new type of electromagnetic actuation material - magneto-controlled shape memory alloy has quietly emerged, and has attracted extensive attention because of its outstanding magneto-induced strain performance.

The advantage of magnetic shape memory alloy is that it has both ferromagnetic and thermoelastic martensitic phase transformation, and combines the advantages of large strain of shape memory alloy and fast response of magnetostrictive material. Using the Zeeman static magnetostatic force of the magnetic field on the unfavorable orientation martensite variants in the alloy, the favorable orientation martensite variants are promoted to grow up, and the unfavorable orientation variants are swallowed up (expressed as the movement of the twin boundary), resulting in macroscopic deformation .

The magnetic shape memory effect can only exist in magnetic alloys with thermoelastic martensitic transformation. Typical ferromagnetic shape memory alloys include Ni-Mn-Ga, Ni-Fe-Ga, Fe-based alloys (Fe-Pd, Fe-Ni-Co-Ti, etc.) and Co-based alloys (Co-Ni, Co-Mn series alloy, etc.) etc.

The reasons why magnetic shape memory alloys are particularly valued are: 1. Excellent performance. The most important performance index is strain, which is 1-2 orders of magnitude higher than that of existing materials. Magnetic shape memory alloys have bidirectional strain effects, and these unique properties are very suitable for the development of new actuators. 2. Compared with giant magnetostrictive materials, the price of this material is lower. Since the giant magnetostrictive material contains a large amount of expensive metal Tb, the price of the magneto-controlled shape memory alloy is about one-tenth of that of the giant magnetostrictive material. 3. There are many important applications. Magnetic shape memory alloys, as smart materials, are the material basis for future national defense and high-tech fields. Its high strain characteristics and high response frequency are expected to be applied in sensors, surface intelligent structures, automatic control, aircraft wing control systems and ultra-high-power ultrasonic transducer technology.

The above descriptions are only preferred embodiments of the present invention, and are not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and changes. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention shall be included within the protection scope of the present invention.

Claims (12)

1. An extendable prosthesis, comprising:

a first prosthesis (10), said first prosthesis (10) having a housing cavity;

a second prosthesis (20), said second prosthesis (20) being connected to said first prosthesis (10), said second prosthesis (20) being movably arranged with respect to said first prosthesis (10);

a deformation structure (30) arranged in the accommodating cavity, wherein one end of the deformation structure (30) is matched with the second prosthesis (20), the deformation structure (30) is made of magnetic memory alloy, the deformation structure (30) can be deformed under the action of an external magnetic field, and the deformation structure (30) drives the second prosthesis (20) to move away from the first prosthesis (10) under the condition of deformation so as to prolong the total length of the extensible prosthesis.

2. The extensible prosthesis of claim 1, wherein the deformation structure (30) is a telescopic structure, the deformation structure (30) being elongated under the action of an external magnetic field to drive the second prosthesis (20) in movement.

3. The extendable prosthesis of claim 2, further comprising:

a first anti-back-out structure, at least a portion of which is movably disposed, the first prosthesis (10) and the second prosthesis (20) both cooperating with the first anti-back-out structure, the first anti-back-out structure being configured to prevent the second prosthesis (20) from moving in a direction closer to the first prosthesis (10) to prevent the second prosthesis (20) from backing out after movement is complete.

4. The extendable prosthesis of claim 3, wherein said first anti-backup structure comprises:

a plurality of first anti-back grooves (41), a plurality of the first anti-back grooves (41) being provided on one of the first prosthesis (10) and the second prosthesis (20);

a first clamping portion (42) used for clamping any one of the first anti-back grooves (41), wherein the first clamping portion (42) is movably arranged on the other one of the first prosthesis (10) and the second prosthesis (20);

when the second prosthesis (20) moves in a direction away from the first prosthesis (10), the first clamping parts (42) avoid the first anti-retreat grooves (41) so that the second prosthesis (20) moves in one direction; after the second prosthesis (20) is moved, the first clamping parts (42) are clamped into the corresponding first anti-withdrawal grooves (41) to prevent the second prosthesis (20) from withdrawing.

5. The extendable prosthesis of claim 2,

the deformation structure (30) is a spiral first spring structure; or the like, or, alternatively,

the deformation structure (30) comprises a plurality of telescopic layers (31) which are connected in sequence, and each telescopic layer (31) can be stretched under the action of an external magnetic field.

6. The extensible prosthesis of claim 5, wherein said deformation structure (30) comprises a plurality of said retractable layers (31), said retractable layers (31) comprising:

two connecting plates (32) that the interval set up and interval set up two backup pad (33) between connecting plate (32), each backup pad (33) all set up to connecting plate (32) slope, under the effect of external magnetic field, each the inclination of backup pad (33) all changes to same direction, in order to change two the distance between connecting plate (32).

7. The extendable prosthesis of claim 1,

a convex rib (51) is arranged on one of the inner wall of the first prosthesis (10) and the outer wall of the second prosthesis (20), and the convex rib (51) extends along the moving direction of the second prosthesis (20);

a sliding groove (52) is arranged on the other one of the inner wall of the first prosthesis (10) and the outer wall of the second prosthesis (20), the sliding groove (52) extends along the moving direction of the second prosthesis (20), and the convex rib (51) is arranged in the sliding groove (52) in a sliding mode.

8. The extensible prosthesis of claim 1, wherein the first prosthesis (10) comprises a lower sleeve (11) and an upper sleeve (12) connected to each other, the deformation structure (30) being arranged inside the lower sleeve (11), the second prosthesis (20) being arranged through the upper sleeve (12) and the lower sleeve (11), a sealing structure being arranged between the upper sleeve (12) and the second prosthesis (20).

9. The extensible prosthesis of claim 8, wherein the end of the upper sleeve (12) facing the lower sleeve (11) has a first stop surface, the second prosthesis (20) comprising:

an intramedullary rod (21), the intramedullary rod (21) passing through the upper sleeve (12), the sealing structure being located between the upper sleeve (12) and the intramedullary rod (21);

the support column comprises a top column (22), the top column (22) is connected with the intramedullary rod (21), at least one part of the top column (22) is located in the lower sleeve (11), the top column (22) is provided with a second limiting surface, the deformation structure (30) is matched with the top column (22) to drive the top column (22) and the intramedullary rod (21) to move, and the second limiting surface is matched with the first limiting surface in a limiting mode to limit the moving distance of the intramedullary rod (21).

10. The extendable prosthesis of claim 8, wherein said extendable prosthesis is a femoral prosthesis, said first prosthesis (10) further comprising:

a femoral condyle (13), the lower sleeve (11) being connected to the femoral condyle (13).

11. The extendable prosthesis of claim 9, further comprising:

the second prevents moving back the structure, the second prevents moving back at least partly of structure and sets up, intramedullary pole (21) with shore (22) all with the cooperation of second prevents moving back the structure, the second prevents moving back the structure and is used for stopping shore (22) are to being close to the direction of deformation structure (30) removes.

12. The extendable prosthesis of claim 11, wherein said second anti-recoil structure comprises:

a plurality of second withdrawal prevention grooves (81), the plurality of second withdrawal prevention grooves (81) being provided on one of the intramedullary rod (21) and the top post (22);

the second clamping portion (82) is used for being clamped with any one of the second anti-back grooves (81), and the second clamping portion (82) is movably arranged on the intramedullary rod (21) and the other of the top columns (22).