Femoral stem test mold

Abstract

The utility model provides a femoral stem test mold, and relates to the field of passive medical instruments. Comprising a first locking mechanism, a second locking mechanism and a handle body, the first locking mechanism is arranged at the top of the handle body, the second locking mechanism is arranged on the side edge of the first locking mechanism, and a preset included angle is formed between the axis of the second locking mechanism and the axis of the first locking mechanism; the first locking mechanism is provided with a groove, and a driving hole is formed in the bottom of the groove. The second locking mechanism is of a protruding structure, and a clamping groove is formed in the side face of the protrusion. A plurality of protruding edges are evenly arranged on the handle body and around the circumference of the handle body, and at least one protruding tooth is arranged between every two adjacent protruding edges. According to the utility model, the quick disassembly and assembly with the thrashing device can be realized, and meanwhile, the two locking parts can be connected with the thrashing device, so that the risk that an operation is stopped due to the fault of a single instrument in the operation process can be avoided, and the safety of the operation is improved; due to the fact that the convex edges and the convex teeth are arranged, the bone marrow cavity can be better matched, and operation accuracy is improved.

Description

Technical Field

[0001] The utility model relates to the technical field of passive medical equipment, in particular to a femoral stem trial mold. Background Art

[0002] During hip replacement surgery, an artificial hip stem is implanted into the human medullary cavity to reshape the hip joint structure and restore its function. Before the actual prosthesis is implanted, a trial model is used to verify that the position, angle, and other dimensions match the patient's anatomy. The stability of the model is also verified to ensure the correct placement of the actual prosthesis.

[0003] In the prior art, most femoral stem test molds only have a single locking part connected to the puller. When the single locking part fails, the femoral stem test mold will be stuck in the femur to be operated on, causing the operation to stop, affecting the efficiency and safety of the operation. The femoral stem test molds in the prior art are mostly cylindrical or rectangular, generally matching the corresponding implant structure shape. Although the test mold with a circular cross-section shape is good for filling the medullary cavity, because the circular cross-section has no major and minor axes and no ridges deeply embedded in the cortical bone, the anti-rotation stability of the cylindrical test mold is relatively poor; the test mold with a rectangular cross-section shape can effectively improve the anti-rotation stability of the test mold through the four corners of the rectangle, but the filling effect on the medullary cavity is poor, that is, the contact area between the bone and the final prosthesis is small, which may affect the bone regeneration in the later stage and cannot achieve a long-term fixation effect. At the same time, the test mold or implant with a rectangular cross-section is relatively round, and the control requirements of the position and angle during implantation are higher. Utility Model Content

[0004] In order to solve the technical problems existing in the prior art, the present invention provides a femoral stem trial mold. The technical solution is as follows:

[0005] A femoral stem trial mold comprises: a first locking mechanism, a second locking mechanism, and a stem body, wherein the first locking mechanism is arranged at the top of the stem body, the second locking mechanism is arranged at the side of the first locking mechanism, and the axis of the second locking mechanism forms a preset angle with the axis of the first locking mechanism;

[0006] A plurality of ridges are evenly arranged on the handle and around the circumference of the handle, and at least one ridge is arranged between two adjacent ridges.

[0007] Optionally, the first locking mechanism has a groove, and the bottom of the groove has a punch hole;

[0008] The second locking mechanism is a protruding structure, and a locking groove is provided on the side surface of the protrusion.

[0009] Optionally, a thread is provided in the punching hole.

[0010] Optionally, the cross-sectional length of the protrusion is greater than the cross-sectional width; and a limiting groove is provided on the end surface of the protrusion.

[0011] Optionally, one side of the first locking mechanism is an abutting surface, the protrusion is provided on the abutting surface, and the abutting surface is used to abut against the second puller.

[0012] Optionally, the protruding height of the protruding teeth is smaller than the protruding height of the protruding ridges.

[0013] Optionally, the taper of the handle body ranges from 2° to 20°.

[0014] Optionally, the number of ridges and teeth provided on the handle is an even number.

[0015] Optionally, four ridges and eight teeth are provided on the handle, and the four ridges are evenly and radially arranged around the handle, and the cross section of the handle is an axisymmetric figure.

[0016] Optionally, on the cross-section of the handle body, the line connecting the protruding vertices of each ridge obtains an outer contour, and the line connecting the protruding vertices of each tooth obtains an inner contour, the inner contour is inside the outer contour and the inner contour is concentrically arranged with the outer contour, the outer contour is circular, elliptical or polygonal; the inner contour is circular, elliptical or polygonal.

[0017] The beneficial effects of the technical solution provided by the embodiment of the utility model include at least:

[0018] The femoral stem trial mold of the technical solution of the present invention is provided with two locking parts respectively connected with pullers of different specifications. When one of the locking parts fails or a puller of a certain specification fails, the operation can be continued through the other locking part or the puller, thereby improving the efficiency of the operation, ensuring the safety of the operation, and avoiding the risk of stopping the operation. The present invention enables the femoral stem trial mold to better fit the cortical bone of the medullary cavity by providing ridges and convex teeth, and can adapt to medullary cavities of different shapes and sizes, thereby improving the accuracy of the operation and facilitating the subsequent selection of the femoral stem. It can also ensure that when the femoral stem trial mold is driven into the medullary cavity, the test mold handle body can be uniformly stressed in the front-to-back and left-to-right directions, that is, when driven in, the axis of the test mold handle body can be ensured to coincide with the axis of the medullary cavity, thereby reducing the difficulty of the surgical operation, reducing the surgical risk for the patient, and reducing the cost. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0020] Figure 1 A schematic structural diagram of a femoral stem trial mold provided by the utility model;

[0021] Figure 2 A top view of a femoral stem trial mold provided by the utility model;

[0022] Figure 3 This is a schematic diagram of a cross section of a femoral stem trial mold provided by the present invention.

[0023] Reference numerals:

[0024] 1. First locking mechanism; 11. Groove; 13. Punch hole; 14. Abutment surface; 2. Second locking mechanism; 21. Retaining groove; 22. Limiting groove; 3. Handle; 5. Handle cross section; 5-1. Raised ridge; 5-2. Raised tooth; 6. Inner contour; 7. Outer contour. DETAILED DESCRIPTION

[0025] To make the purpose, technical solutions, and advantages of the embodiments of the present invention more clear, the technical solutions of the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of them. Based on the described embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0026] Unless otherwise defined, the technical or scientific terms used in this utility model shall have the usual meanings understood by persons of ordinary skill in the field to which this utility model belongs. The words "first", "second" and similar terms used in this utility model do not indicate any order, quantity or importance, but are only used to distinguish different components. Similarly, words such as "one", "an" or "the" do not indicate a quantity limitation, but rather indicate the existence of at least one. Words such as "include" or "comprise" mean that the elements or objects preceding the word include the elements or objects listed after the word and their equivalents, without excluding other elements or objects. Words such as "connect" or "connected" are not limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect.

[0027] It should be noted that the terms "up", "down", "left", "right", "front" and "back" used in the present invention are only used to indicate relative position relationships. When the absolute position of the object being described changes, the relative position relationship may also change accordingly.

[0028] like Figure 1-Figure 3 As shown, this embodiment provides a femoral stem trial mold, including: a first locking mechanism 1, a second locking mechanism 2 and a stem body 3, the first locking mechanism 1 is arranged at the top of the stem body 3, the second locking mechanism 2 is arranged on the side of the first locking mechanism 1, and the second locking mechanism 2 forms a preset angle with the axis of the first locking mechanism 1; the first locking mechanism 1 has a groove 11, and the bottom of the groove 11 has a punch hole 13; the second locking mechanism 2 is a convex structure, and the side of the convex is provided with a locking groove 21.

[0029] The femoral stem trial mold of the technical solution of the present invention is provided with two locking mechanisms which are respectively connected to pullers of different specifications. When one of the locking parts fails or a puller of a certain specification fails, the operation can be continued through the other locking part or puller, thereby improving the efficiency of the operation, ensuring the safety of the operation, and avoiding the risk of the operation being stopped.

[0030] Furthermore, the shape of the first locking mechanism 1 is the same as the shape of the shoulder of the femoral stem trial mold in the prior art, and the second locking mechanism is a convex structure, the upper and lower surfaces of the convexity are arc-shaped structures, and the remaining two side surfaces are planar structures. The first locking mechanism 1 is arranged at the top of the handle body 3, and the second locking mechanism 2 is arranged on the side of the first locking mechanism 1, and the axis of the second locking mechanism 2 is at a preset angle with the axis of the first locking mechanism 1.

[0031] The top of the first locking mechanism 1 is provided with a groove 11, and the bottom of the groove 11 has a punching hole 13 with a threaded interior. The punching hole 3 is provided to facilitate the mating and locking with the first puller, enabling rapid assembly and disassembly during surgery. The surface where the first locking mechanism 1 connects to the second locking mechanism 2 is an abutment surface 14, and the raised structure of the second locking mechanism 2 is provided on the abutment surface 14. When the second puller is connected to the second locking mechanism 2, the abutment surface 14 abuts against the end face of the second puller opening.

[0032] A locking groove 21 is provided on the side of the second locking mechanism 2, and the cross-sectional length of the second locking mechanism 2 is greater than the cross-sectional width of the protruding structure of the second locking mechanism 2. A limiting groove 22 is provided on the end surface of the second locking mechanism 2.

[0033] At least two ridges 5-1 are evenly arranged on the handle body 3 and around the circumference of the handle body 3. The extension direction of the ridges 5-1 is the same as the extension direction of the handle body 3, that is, the length of the ridges 5-1 is equal to the length of the handle body 3, and the length of the ridges 5-1 refers to the length of the longest side of the ridges 5-1; at least one ridge 5-2 is arranged between two adjacent ridges 5-1, and the extension direction of the ridges 5-2 is the same as the extension direction of the handle body 3, that is, the length of the ridges 5-2 is equal to the length of the handle body 3, and the length of the ridges 5-2 refers to the length of the longest side of the ridges 5-2, and the number of ridges 5-1 and the number of ridges 5-2 are even numbers; the protruding height of the ridges 5-2 is less than the protruding height of the ridges 5-1.

[0034] In one embodiment, the number of the protruding teeth 5 - 2 provided between two adjacent protruding ridges 5 - 1 is an even number, and the number of the protruding ridges 5 - 1 is also an even number.

[0035] In one embodiment, four ridges 5-1 are evenly distributed around the circumference of the handle 3. Two teeth 5-2 are located between two adjacent ridges 5-1, for a total of eight teeth 5-2. In this embodiment, the two teeth 5-2 located between two adjacent ridges 5-1 can be symmetrical. The four ridges 5-1 are evenly distributed radially around the circumference of the handle 3, and the handle cross section 5 is an axially symmetrical shape.

[0036] This design can evenly distribute the ridges 5-1 and the teeth 5-2 on the cross-sectional circumference of the handle body 3, and can also ensure that when the femoral stem trial mold is driven into the bone marrow cavity, the test mold handle body can be evenly stressed in the front-to-back and left-to-right directions. That is, when the femoral stem trial mold is driven into the bone marrow cavity, the axis of the test mold handle body can be ensured to coincide with the axis of the bone marrow cavity, thereby reducing the difficulty of the surgical operation, reducing the surgical risk for the patient, and reducing costs.

[0037] The ridges 5-1 can be deeply embedded in the cortical bone of the human medullary cavity when implanted into the medullary cavity, ensuring excellent anti-rotational stability. The ridges 5-2 can directly press against the cortical bone of the medullary cavity, achieving excellent anti-sinking effect. This can well simulate the state and effect of the prosthetic implant when it is installed, improving the adaptability and stability of the angle size of the artificial hip joint femoral stem after implantation into the human medullary cavity, while reducing the occurrence of incorrect unpacking of the prosthesis during surgery due to uncertain specifications. In order for the corresponding implant femoral stem to better match the cortical bone conditions and anatomical characteristics of the patient's medullary cavity, the number of ridges 5-1 and the number of ridges 5-2 can be adjusted within the range of 2-40, and the ridges 5-1 and ridges 5-2 can be designed to be arranged in an alternating manner according to any size and position, or in a non-alternating alternating arrangement.

[0038] The handle 3 includes a proximal end and a distal end. The proximal end is connected to the first locking mechanism 1. The handle 3 is a tapered rod. The shape of the handle 3 is similar to that of the prior art and will not be described in detail here. The diameter of the proximal end is greater than that of the distal end. The taper of the handle 3 ranges from 2° to 20°, meaning the angle of inclination between the proximal and distal ends is between 2° and 20°. In this embodiment, the handle 3 has a 5° taper, which further improves the stability of the femoral stem trial mold within the medullary cavity and prevents excessive sinking.

[0039] The side surface of the first locking mechanism 1 away from the second locking mechanism 2 is inclined toward the second locking mechanism 2, and the inclination angle ranges from 0.1° to 20°. In this embodiment, the inclination angle is 1°, which makes it more convenient to implant the prosthesis during surgery.

[0040] A punching hole 13 is provided on the top surface of the first locking mechanism 1 for connecting a fixed implant device such as the first puller 6, which serves as an auxiliary pulling interface when the second locking mechanism 2 fails. It can achieve a firm connection with other implant devices and at the same time restrict the relative axial rotation of the two, making it convenient to control the rotation angle when implanting the trial mold during surgery.

[0041] The surface of the femoral stem test mold is sandblasted, and the surface roughness Ra of the femoral stem test mold is 0.8-6.3, which can better simulate the friction resistance and tactile feedback of the implant prosthesis during implantation.

[0042] On the cross section 5 of the handle, the line connecting the protruding vertices of each ridge 5-1 forms an outer contour 7, and the line connecting the protruding vertices of each tooth 5-2 forms an inner contour 6. The inner contour 6 is located inside the outer contour 7 and is concentric with the outer contour 7. The inner contour 6 can be circular, elliptical, or polygonal, and the outer contour 7 can be circular, elliptical, or polygonal. This design can better adapt to the cortical bone of the patient's medullary cavity and the anatomical characteristics of the bone.

[0043] When the inner contour 6 is elliptical, the ratio of the major axis of the inner contour 6 to the minor axis of the inner contour 6 is in the range of 1-10. When the outer contour 7 is elliptical, the ratio of the major axis of the outer contour 7 to the minor axis of the outer contour 7 is in the range of 1-10. When the inner contour 6 is polygonal, the size of each convex tooth 5-2 is different and the protrusion height is also different. When the outer contour 7 is polygonal, the size of each convex ridge 5-2 is different and the protrusion height is also different. When both the inner contour 6 and the outer contour 7 are circular, the radius of the inner contour 6 is smaller than the radius of the outer contour 7. The protrusion height is the distance from the protrusion vertex to the surface of the handle body 3.

[0044] In the technical solution of the present invention, the second locking mechanism 2 is provided with a locking groove 21, which is convenient for matching and locking with the interface of the second puller 5, so as to realize rapid disassembly and assembly during the operation;

[0045] The ridge 5-1 is designed to be deeply embedded in the cortical bone of the human medullary cavity when implanted into the medullary cavity, ensuring excellent anti-rotational stability; the convex teeth 5-2 are designed to directly press against the cortical bone of the medullary cavity, achieving excellent anti-sinking effect. The design of the ridge 5-1 and the convex teeth 5-2 can well simulate the state and effect of the prosthetic implant when it is installed, and can better adapt to the cortical bone of the patient's medullary cavity and the anatomical characteristics of the bone.

[0046] The inner contour 6 and the outer contour 7 of this solution can be polygonal, elliptical or circular, which can better adapt to the cortical bone of the patient's medullary cavity and the anatomical characteristics of the bone.

[0047] This solution aims to improve the adaptability and stability of the angle size of the artificial hip joint femoral stem after implantation in the human medullary cavity, while reducing the occurrence of incorrect unpacking of the prosthesis during surgery due to uncertain size.

[0048] The femoral stem trial mold of this solution is provided with two locking parts which are respectively connected to pullers of different specifications. When one of the locking parts fails or a certain specification of puller fails, the operation can be continued through the other locking part or puller, thereby improving the efficiency of the operation, ensuring the safety of the operation, and avoiding the risk of stopping the operation. This solution enables the femoral stem trial mold to better fit the cortical bone of the medullary cavity by providing ridges and convex teeth, and can adapt to medullary cavities of different shapes and sizes, thereby improving the accuracy of the operation and facilitating the subsequent selection of femoral stems. It can also ensure that when the femoral stem trial mold is driven into the medullary cavity, the test mold handle body can be evenly stressed in the front-to-back and left-to-right directions, that is, when driven in, the axis of the test mold handle body can be ensured to coincide with the axis of the medullary cavity, thereby reducing the difficulty of the surgical operation, reducing the surgical risk for the patient, and reducing costs.

[0049] The following points need to be explained:

[0050] (1) The drawings of the embodiments of the present invention only relate to the structures related to the embodiments of the present invention. Other structures may refer to conventional designs.

[0051] (2) For the sake of clarity, the thickness of layers or regions in the drawings used to describe the embodiments of the present invention are exaggerated or reduced, that is, these drawings are not drawn to scale. It is understood that when an element such as a layer, film, region, or substrate is referred to as being "on" or "under" another element, the element may be "directly" "on" or "under" the other element or intervening elements may be present.

[0052] (3) In the absence of conflict, the embodiments of the present invention and the features therein may be combined with each other to obtain new embodiments.

[0053] The above are only specific implementation methods of the present invention, but the protection scope of the present invention is not limited thereto. The protection scope of the present invention shall be based on the protection scope of the claims.

Claims

1. A femoral stem trial mold, characterized in that: include: A first locking mechanism, a second locking mechanism, and a handle body, wherein the first locking mechanism is arranged at the top of the handle body, and the second locking mechanism is arranged at the side of the first locking mechanism, and the axis of the second locking mechanism and the first locking mechanism form a preset angle; A plurality of ridges are evenly arranged on the handle and around the circumference of the handle, and at least one ridge is arranged between two adjacent ridges.

2. The femoral stem trial mold according to claim 1, characterized in that: The first locking mechanism has a groove, and the bottom of the groove has a punch hole; The second locking mechanism is a protruding structure, and a locking groove is provided on the side surface of the protrusion.

3. The femoral stem trial mold according to claim 2, characterized in that: A thread is arranged in the punching hole.

4. The femoral stem trial mold according to claim 2, characterized in that: The cross-sectional length of the protrusion is greater than the cross-sectional width; and a limiting groove is provided on the end surface of the protrusion.

5. The femoral stem trial mold according to claim 2, characterized in that: One side of the first locking mechanism is an abutting surface, the protrusion is arranged on the abutting surface, and the abutting surface is used to abut against the second puller.

6. The femoral stem trial mold according to claim 1, characterized in that: The protruding height of the protruding teeth is smaller than the protruding height of the protruding ridges.

7. The femoral stem trial mold according to claim 1, characterized in that: The taper of the handle body ranges from 2° to 20°.

8. The femoral stem trial mold according to claim 1, characterized in that: Four ridges and eight teeth are arranged on the handle, and the four ridges are evenly arranged radially around the handle. The cross section of the handle is an axisymmetric figure.

9. The femoral stem trial mold according to claim 1, characterized in that: On the cross section of the handle body, the line connecting the protruding vertices of each ridge obtains an outer contour, and the line connecting the protruding vertices of each tooth obtains an inner contour, the inner contour is inside the outer contour and is concentrically arranged with the outer contour, the outer contour is circular, elliptical or polygonal; the inner contour is circular, elliptical or polygonal.

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