A proximal shaping device

Abstract

The present invention provides a proximal forming instrument, comprising a distal trial mold (1), a proximal trial mold (3) and a proximal former (4), wherein the proximal end surface of the distal trial mold (1) is provided with a distal trial mold indexing tooth (12), and the distal end surfaces of the proximal trial mold (3) and the proximal former (4) are respectively provided with a proximal trial mold indexing tooth (31) and a former indexing tooth (41) that match the distal trial mold indexing tooth (12). The proximal forming instrument has an indexing function and can accurately align and position; the distal trial mold has an anti-rotation function; a pin provided on the hole wall of the center hole of the proximal former can prevent the screw carried by it from falling off; after the proximal former is used, the extraction groove provided at the proximal end thereof makes it easier to extract; the vertical plate of the aiming device is provided with a scale for convenient processing and easier alignment; in addition, the notch milled at the proximal end of the femur by the proximal forming instrument can prevent the femoral stem prosthesis from sinking and rotating.

Description

Technical Field

[0001] The present invention belongs to the technical field of orthopedic medical devices, and in particular relates to a proximal forming device. Background Art

[0002] Developmental dysplasia of the hip (DDH), also known as congenital hip dislocation, is a leading cause of limb disability in children. The incidence of DDH in my country is approximately 3.9‰, with a male-to-female ratio of approximately 1:6. Developmental defects in the acetabulum, proximal femur, and joint capsule lead to joint instability, ultimately leading to hip dislocation.

[0003] When DDH develops to the middle or late stages, it may be complicated by hip osteoarthritis. The patient's articular cartilage is destroyed, subchondral bone is exposed and cystic, bone hyperplasia and sclerosis appear ivory-like, and the joint space narrows or even disappears. At this time, hip joint movement is difficult or almost non-existent, and clinical symptoms are obvious. Total hip replacement with an artificial hip prosthesis is an ideal treatment option. The femoral stem is one of the key components of the artificial hip prosthesis. Proximal shaping is a necessary step in the implantation of the femoral stem, and proximal shaping requires the use of a proximal shaping instrument. Existing proximal shaping instruments, such as the S-ROM® sold by DePuy Orthopaedics, Inc., perform proximal shaping directly in the pre-processed proximal femoral medullary cavity. The proximal and distal ends of the femoral stem are then indexed and installed with the collar to align the neck of the femoral stem with the original femoral neck. This modular femoral stem has the risk of loosening after implantation, which can affect the patient's movements and even cause implant failure, necessitating further surgical revision. Therefore, a new, one-piece femoral stem is needed to completely avoid this risk. However, this one-piece femoral stem lacks an indexing function and must be indexed during proximal shaping to align the proximal groove of the femoral stem with the original femoral neck. This ensures that the femoral neck of the femoral stem is aligned with the original femoral neck after implantation. Existing proximal shaping instruments cannot meet this functional requirement. Summary of the Invention

[0004] In view of the shortcomings of the existing technology, the purpose of the present invention is to provide a proximal forming instrument to solve the problems in the existing technology that the proximal forming instrument does not have a grading function, cannot be accurately aligned and positioned, and is not suitable for integrated hip-first femoral stem implantation surgery.

[0005] To achieve this object, the present invention adopts the following technical solutions:

[0006] A proximal forming device comprises a distal trial mold, a proximal trial mold and a proximal former. The proximal end face of the distal trial mold is provided with distal trial mold indexing teeth, and the distal end faces of the proximal trial mold and the proximal former are respectively provided with proximal trial mold indexing teeth and former indexing teeth that match the distal trial mold indexing teeth.

[0007] Preferably, the number of the distal trial mold indexing teeth, the proximal trial mold indexing teeth and the former indexing teeth is 9 to 72, such as 12, 18, 24 or 36.

[0008] Preferably, the distal trial mold is a cone structure with a taper of 2° to 8°, such as 3°, 4°, 5° or 6°.

[0009] Preferably, the outer conical surface of the distal trial mold forms a convex ridge.

[0010] Preferably, a center hole is provided at the center of the proximal end face of the distal trial mold, the center hole comprises a light hole and a threaded hole that are interconnected, and the threaded hole is away from the proximal end face.

[0011] Preferably, the proximal trial mold and the proximal former are both provided with a trial mold screw that cooperates with the distal trial mold, and the tail of the trial mold screw includes an optical axis portion and a threaded portion in sequence from the proximal end to the distal end, and the distal end faces of the proximal trial mold and the proximal former are respectively provided with a proximal optical hole and a former center hole; when the proximal trial mold or the proximal former cooperates with the distal trial mold, the optical axis portion of the trial mold screw is located in the proximal optical hole or the former center hole and the optical hole of the distal trial mold; the threaded portion of the trial mold screw cooperates with the threaded hole of the distal trial mold.

[0012] Preferably, a pin is provided on the wall of the center hole of the proximal former to prevent the trial mold screw from falling out of the proximal former.

[0013] Preferably, the proximal end of the proximal former is provided with a pulling out groove for pulling out the proximal former.

[0014] Preferably, the proximal forming instrument also includes a sight and a proximal forming milling cutter, the proximal forming instrument is provided with a sight hole, and the sight is placed in the sight hole; the sight includes a handle, a rod fixed to the lower end of the handle and a vertical plate fixed to the side wall of the rod, and a milling cutter holder is provided on the vertical plate; the proximal forming milling cutter is placed in the milling cutter holder.

[0015] Preferably, a groove is formed at the distal end of the rod, and the handle is a handle whose surface is covered with silicone; and scale lines are provided on the vertical plate.

[0016] Compared with the prior art, the present invention has the following beneficial effects:

[0017] The proximal shaping instrument provided by the present invention has a graduation function and is suitable for use in one-piece femoral stem implantation surgery, making positioning more accurate.

[0018] The optical holes provided on the distal trial mold, the proximal trial mold and the proximal former of the proximal forming device provided by the present invention have the function of assisting the indexing teeth to cooperate, thereby further improving the positioning accuracy.

[0019] The distal trial mold of the proximal forming device provided by the present invention has an anti-rotation function;

[0020] The pin provided on the hole wall of the central hole of the proximal end former of the proximal end forming device provided by the present invention can prevent the screw provided therewith from falling off;

[0021] After the proximal end shaping device of the present invention is used, it is easy to pull out due to the extraction groove provided at the proximal end thereof;

[0022] The proximal forming instrument provided by the present invention has a vertical plate with a scale on its aimer, which is convenient for processing and easier to align, and is beneficial for controlling the milling depth of the proximal forming milling cutter; the proximal forming instrument provided by the present invention can mill a notch at the proximal end of the femur, and the notch can cooperate with the extraction groove of the neck of the femoral stem prosthesis to prevent the femoral stem prosthesis from sinking and rotating. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] FIG1 is a schematic diagram of the assembly of the proximal shaping device provided in Example 1 at the marking stage;

[0024] Figure 2 This is a schematic diagram of the assembly of the proximal forming device provided in Example 1 during the forming stage;

[0025] Figure 3 is a top view of the distal trial mold of the proximal molding device provided in Example 1;

[0026] Figure 4 yes Figure 3 Cross-section along the AA direction;

[0027] Figure 5 is a bottom view of the proximal trial mold in the proximal molding device provided in Example 1;

[0028] Figure 6 yes Figure 5 Cross-section along the middle BB direction;

[0029] Figure 7 is a bottom view of the proximal end former in the proximal end forming apparatus provided in Example 1;

[0030] Figure 8 yes Figure 7 Cross-section in the mid-CC direction;

[0031] Figure 9 is a schematic structural diagram of the aimer in the proximal shaping device provided in Example 1;

[0032] Figure 10 It is a structural schematic diagram of the proximal forming milling cutter in the proximal forming instrument provided in Example 1.

[0033] in:

[0034] 1 Distal trial mold 2 Trial mold screw

[0035] 3 Proximal test mold 4 Proximal former

[0036] 5 Sight 6 Proximal forming milling cutter

[0037] 11 ridge 12 distal test die indexing teeth

[0038] 13 center hole

[0039] 31 proximal test die indexing tooth 32 neck

[0040] 33 Proximal light hole 34 Connecting part

[0041] 41 former indexing tooth 42 pin

[0042] 43 Rod body 44 Aiming hole

[0043] 45 center hole of former 46 extraction groove

[0044] 51 Rod 52 Milling cutter holder

[0045] 53 scale line 54 handle

[0046] 55 vertical plate 56 positioning hole

[0047] 61 pin 62 cutting edge 63 Positioning shaft 64 Electric drill interface. DETAILED DESCRIPTION

[0048] In the description of the present invention, it should be understood that the orientations or positional relationships indicated by the terms "center", "upper", "lower", "inside", "outside", etc. are 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, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, features defined as "first", "second", etc. may explicitly or implicitly include one or more of the features. In the description of the present invention, unless otherwise specified, "multiple" means two or more.

[0049] In the description of the present invention, it should be noted that, unless otherwise expressly specified or limited, the terms "mounted," "connected," and "connected" should be understood in a broad sense. For example, they may refer to fixed connections, detachable connections, or integral connections; mechanical connections or electrical connections; direct connections or indirect connections through an intermediate medium; and internal communication between two components. Those skilled in the art will understand the specific meanings of the above terms in the present invention based on specific circumstances.

[0050] The technical solution of the present invention will be further described below with reference to the accompanying drawings and through specific implementation methods.

[0051] Unless otherwise specified below, distal and proximal refer to the distance from the torso.

[0052] Example 1

[0053] like Figure 1 、 2 As shown, a proximal forming instrument includes a distal trial mold 1, which is connected to a proximal trial mold 3 or a proximal former 4 through a trial mold screw 2, a sight 5 penetrates into the proximal former 4, and a proximal forming milling cutter 6 is installed on the sight 5.

[0054] The proximal end face of the distal trial mold 1 is provided with a distal trial mold dividing tooth 12, and the distal end faces of the proximal trial mold 3 and the proximal former 4 are respectively provided with a proximal trial mold dividing tooth 31 and a former dividing tooth 41 that match the distal trial mold dividing tooth 12; this structure can realize the dividing function, can be suitable for one-piece hip femoral stem implantation surgery, and is easy to operate and easy to align.

[0055] The number of the distal trial mold indexing teeth 12 , the proximal trial mold indexing teeth 31 and the former indexing teeth 41 is 9 to 72, and is 36 in this embodiment.

[0056] like Figure 3 、 4 As shown, the distal trial mold 1 has a conical structure with a taper of 2° to 8°, and in this embodiment, 5°. The outer conical surface forms four ridges 11. When the distal trial mold 1 is inserted into the femoral medullary cavity, the ridges 11 will embed into the cortical bone of the femoral medullary cavity, preventing the distal trial mold 1 from rotating. The conical structure facilitates the insertion of the distal trial mold 1.

[0057] A center hole 13 is provided at the center of the proximal end surface of the distal trial mold 1. The center hole 13 includes a light hole and a threaded hole that are interconnected, and the threaded hole is provided at one side of the distal end.

[0058] The proximal test mold 3 and the proximal former 4 are both provided with a test mold screw 2 that cooperates with the distal test mold 1. The tail of the test mold screw 2 includes an optical axis portion and a threaded portion from the proximal end to the distal end. The centers of the distal end faces of the proximal test mold 3 and the proximal former 4 are respectively provided with a proximal optical hole 33 and a former center hole 45; when the proximal test mold 3 or the proximal former 4 cooperates with the distal test mold 1, the optical axis portion of the test mold screw 2 is located in the proximal optical hole 33 or the former center hole 45 and the optical hole of the distal test mold 1; the threaded portion of the test mold screw 2 cooperates with the threaded hole of the distal test mold 1.

[0059] The function of the trial mold screw is to fix the distal trial mold and the proximal trial mold or the proximal former, and at the same time, the trial mold screw also plays a role in assisting the matching of the indexing teeth.

[0060] The hole wall of the former center hole 45 of the proximal former 4 is provided with a pin 42. The pin 42 can ensure that the screw it carries will not fall out of the proximal former when loosened, causing loss or falling into the medullary cavity, causing surgical difficulties.

[0061] The proximal end of the proximal former 4 is provided with a pulling-out groove 46 for pulling out the proximal former, so that the proximal former 4 and the distal trial mold 1 can be pulled out together, which is easy to operate.

[0062] like Figure 9 As shown, the sight 5 includes a handle 54, a rod 51 fixed to the lower end of the handle 54 and a vertical plate 55 fixed to the side wall of the rod 51, and a milling cutter holder 52 is provided on the vertical plate 55; a positioning hole 56 is formed at the distal end of the rod 51.

[0063] The handle 54 is a handle covered with silicone; a scale line 53 is provided on the vertical plate 55, and when the sight moves downward until the scale line on the vertical plate 55 is flush with the upper end surface of the proximal former 4, the milling reaches the required depth.

[0064] In addition to the above improvements, the designs of the proximal trial mold, proximal former, aimer, and proximal forming milling cutter can refer to the corresponding instruments in S-ROM® sold by DePuy Orthopaedics, Inc.

[0065] like Figure 5 、 6 As shown, the proximal trial mold 3 includes a connecting portion 34 and a neck 32 , the neck 32 and the connecting portion 34 form an angle, and a proximal light hole 33 is provided at the center of the connecting portion 34 for connecting with the distal trial mold 1 .

[0066] like Figure 7 、 8As shown, the proximal former 4 includes a rod body 43, a former center hole 45 is set in the center of the rod body 43, and an aiming hole 44 is set on the side wall of the former center hole 45 so that the center hole is connected to the outside; the aiming hole 44 is used to place the rod part 51 of the aimer 5.

[0067] like Figure 10 As shown, the proximal forming milling cutter 6 includes a pin shaft 61 , and the pin shaft 61 is provided with a cutting edge 62 , a positioning shaft 63 and an electric drill interface 64 in sequence from the distal end to the proximal end.

[0068] Example 2

[0069] In this embodiment, some structures of the embodiment 1 are improved, and some structures are the same as those of the embodiment 1.

[0070] The number of the distal trial mold indexing teeth 12 , the proximal trial mold indexing teeth 31 and the former indexing teeth 41 is 9.

[0071] The distal test mold 1 is a cone structure with a taper of 2°.

[0072] Example 3

[0073] In this embodiment, some structures of the embodiment 1 are improved, and some structures are the same as those of the embodiment 1.

[0074] The number of the distal trial mold indexing teeth 12 , the proximal trial mold indexing teeth 31 and the former indexing teeth 41 is 72.

[0075] The distal test mold 1 is a cone structure with a taper of 8°.

[0076] The operation method for performing surgery using the proximal shaping instrument described in any one of Examples 1 to 3 is as follows:

[0077] (1) Insert the distal trial mold into the femoral medullary cavity, then insert the proximal trial mold, adjust the matching of the proximal trial mold and the distal trial mold end face indexing teeth so that the neck direction of the proximal trial mold is aligned with the original femoral neck direction, and then connect the distal trial mold and the proximal trial mold with the trial mold screw. Mark the neck direction and remove the trial mold screw after completing the trial assembly, and remove the proximal trial mold;

[0078] (2) The proximal former and the distal test mold are matched through the indexing teeth set on the end face. Since the indexing teeth set on the distal end face of the proximal former are completely consistent with the indexing teeth of the proximal test mold, and the neck direction marked in the previous step can be referred to when matching, it can be ensured that when the proximal former and the distal test mold are matched, the direction of the aiming hole of the proximal former is consistent with the direction marked before. After determining the direction, the proximal former is installed and fastened to the distal test mold with the screws provided in the proximal former;

[0079] (3) The rod of the aimer is inserted into the center hole of the proximal former, and the rod of the aimer is stuck in the aiming hole of the proximal former to ensure that the milling direction is consistent with the direction marked before. This ensures that when the femoral stem is installed in the milled groove, the neck direction of the femoral stem is consistent with the original femoral neck direction; there are scale lines on the vertical plate, and when the aimer moves downward until the scale lines on the vertical plate are flush with the upper end surface of the proximal former, it means that the milling has reached the required depth; the pin shaft of the proximal forming milling cutter head is inserted into the hole of the aimer rod, the front section has a cutting edge, the middle section positioning shaft is inserted into the milling cutter holder hole of the aimer for positioning, and the tail section has an electric drill interface. The proximal forming milling cutter rotates with the electric drill to form a milling motion to complete the proximal forming operation.

[0080] (4) After completing the proximal forming operation, a special extraction instrument can be used to extract the proximal former and the distal trial mold together using the proximal groove.

[0081] The proximal forming instrument provided by the present invention solves the problems that the original proximal forming instrument structure has no indexing function and cannot meet the needs of integrated femoral stem implantation surgery; the optical holes provided in the distal trial mold, the proximal trial mold and the proximal former have the function of assisting the indexing teeth to cooperate; the distal trial mold has an anti-rotation function; the pin provided on the hole wall of the center hole of the proximal former can prevent the screws provided with it from falling off; after the proximal former is used, it is easier to pull out due to the extraction groove provided at its proximal end; the vertical plate of the aiming device is provided with a scale for convenient processing and easier to align; the notch milled out by the forming instrument at the proximal end of the femur can prevent the integrated femoral stem prosthesis from sinking and rotating. The applicant declares that the above is only a specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Those skilled in the art should understand that any changes or replacements that can be easily thought of by those skilled in the art within the technical scope disclosed by the present invention fall within the protection scope and disclosure scope of the present invention.

Claims

1. A proximal forming device, comprising a distal trial mold (1), a proximal trial mold (3) and a proximal former (4), characterized in that: The distal end surface of the distal test mold (1) is provided with a distal test mold indexing tooth (12), and the distal end surfaces of the proximal test mold (3) and the proximal former (4) are respectively provided with a proximal test mold indexing tooth (31) and a former indexing tooth (41) that match the distal test mold indexing tooth (12); The distal end trial mold (1) is a cone structure; The outer conical surface of the distal end trial mold (1) forms a convex ridge (11); The proximal forming device further comprises a sight (5) and a proximal forming milling cutter (6); a sighting hole (44) is provided in the proximal forming device (4), and the sight (5) is placed in the sighting hole (44); the sight (5) comprises a handle (54), a rod (51) fixed to the lower end of the handle (54), and a vertical plate (55) fixed to the side wall of the rod (51); a milling cutter holder (52) is provided on the vertical plate (55); the proximal forming milling cutter (6) is placed in the milling cutter holder (52); A center hole (13) is provided at the center of the proximal end surface of the distal end trial mold (1), the center hole (13) comprises a light hole and a threaded hole that are interconnected, and the threaded hole is away from the proximal end surface; The proximal test mold (3) and the proximal former (4) are both provided with a test mold screw (2) that matches the distal test mold (1), and the tail of the test mold screw (2) includes an optical axis portion and a threaded portion in sequence from the proximal end to the distal end, and the distal end faces of the proximal test mold (3) and the proximal former (4) are respectively provided with a proximal optical hole (33) and a former center hole (45); when the proximal test mold (3) or the proximal former (4) matches the distal test mold (1), the optical axis portion of the test mold screw (2) is located in the proximal optical hole (33) or the former center hole (45) and the optical hole of the distal test mold (1); the threaded portion of the test mold screw (2) matches the threaded hole of the distal test mold (1); A positioning hole (56) is formed at the distal end of the rod portion (51); and a scale line (53) is provided on the vertical plate (55).

2. The proximal end shaping device according to claim 1, characterized in that: The number of the distal end trial mold indexing teeth (12), the proximal end trial mold indexing teeth (31) and the former indexing teeth (41) is 9 to 72.

3. The proximal end shaping device according to claim 1 or 2, characterized in that: The taper of the distal end trial mold (1) is 2° to 8°.

4. The proximal end shaping device according to claim 1, characterized in that: A pin (42) is provided on the hole wall of the center hole (45) of the proximal former (4) to prevent the trial mold screw from falling out of the proximal former (4).

5. The proximal end shaping device according to claim 1 or 2, characterized in that: The proximal end of the proximal former (4) is provided with a pulling-out groove (46) for pulling out the proximal former.

6. The proximal end shaping device according to claim 1, characterized in that: A positioning hole (56) is formed at the distal end of the rod portion (51), and the handle (54) is a handle with a surface covered with silica gel; and a scale line (53) is provided on the vertical plate (55).

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