Disposable acetabular reamer and method of changing inserts

Abstract

The application discloses a disposable acetabular reamer and a tool block replacing method, wherein the disposable acetabular reamer comprises a hemispherical tool holder and a reamer, the hemispherical tool holder is a hemispherical shell structure formed by plastic injection molding, a cross head for clamping is integrally formed at the bottom of the hemispherical tool holder, a plurality of reamer holes are formed in the shell of the hemispherical tool holder, the reamer is fixedly connected to one side of the reamer hole, and the cantilever end of the reamer is inserted into the reamer hole and protrudes from the outer spherical wall of the hemispherical tool holder. The hemispherical tool holder made of plastic material is adopted to support the reamer, the cost of expensive metal materials is reduced, and cross infection is avoided.

Description

Technical Field

[0001] This invention relates to the field of orthopedic surgical tools, and more particularly to a disposable acetabular reamer and a method for replacing the reamer. Background Technology

[0002] An acetabular reamer is a medical instrument used to remove acetabular cartilage and some bone tissue. It is a specialized surgical instrument used in total hip arthroplasty to reshape the acetabular fossa to the appropriate shape and size for accurate placement of the artificial acetabular prosthesis.

[0003] Existing acetabular reamers are hemispherical metal designs with sharp cutting edges covering their surfaces for efficient bone cutting. Most are made of stainless steel or titanium alloy in a single piece. For example, the applicant's earlier patent application, publication number CN209059342U, discloses an acetabular reamer that reduces bone cutting time and creates a regular cutting texture. It includes a hemispherical shell and a support rod welded to the circular opening of the hemispherical shell. The hemispherical shell has multiple cutting holes, dividing it into at least five latitudinal intervals from bottom to top. The cutting holes are arranged in groups of three within different latitudinal intervals. Within any latitudinal interval, the latitude of the three cutting holes gradually increases / decreases, and the longitudes of the three cutting holes differ by 120° sequentially. The two cutting holes located in adjacent latitudinal intervals with the smallest latitude difference have a longitude difference between 20° and 100°. In this patented acetabular reamer, the cutting holes are integrally formed on the hemispherical stainless steel shell. This one-piece molding method, due to the presence of grooves in the cutting holes, makes it prone to incomplete cleaning and disinfection, and repeated use may lead to cross-infection. Constructing the entire device from medical-grade stainless steel or titanium alloy, discarding it after a single use results in significant waste and increases surgical costs.

[0004] To overcome the above problems, a disposable acetabular reamer needs to be developed. Summary of the Invention

[0005] The purpose of this invention is to provide a disposable acetabular file that uses a plastic hemispherical holder to support the file, reducing the cost of expensive metal materials and avoiding cross-infection.

[0006] To solve the above-mentioned technical problems, the present invention adopts the following technical solution:

[0007] The present invention relates to a disposable acetabular file, comprising: a hemispherical file holder and a file, wherein the hemispherical file holder is a hemispherical shell structure formed by plastic injection molding, and the bottom of the hemispherical file holder is integrally injection molded with a crosshead for mounting; the shell of the hemispherical file holder has multiple filing holes, the file is fixedly connected to one side of the filing holes, and the cantilever end of the file extends into the filing hole and protrudes from the outer spherical wall of the hemispherical file holder.

[0008] Furthermore, the file is specifically made of a blade, the root of which is directly injection molded and anchored within the housing material of the hemispherical tool holder, and the cantilever end face of the blade is set as a cutting edge.

[0009] Furthermore, the cantilever end of the blade is an arc-shaped plate with inwardly bent edges at both ends.

[0010] Furthermore, the embedded section of the blade is provided with anchoring holes, and the anchoring holes are filled with the shell material of the hemispherical blade holder.

[0011] Furthermore, the file is specifically a blade block, the file hole is a horseshoe-shaped through hole, and the outer wall of the hemispherical blade holder is recessed into a groove on one side of the straight edge of the file hole. The blade block is installed in the groove by screws.

[0012] Furthermore, the top surface of the blade block is provided with a countersunk through hole, and the countersunk screw passes through the countersunk through hole and is threaded to the threaded hole on the bottom surface of the blade groove.

[0013] Furthermore, the hemispherical tool holder has a thickened protrusion added to the bottom surface at the location of the threaded hole.

[0014] Furthermore, the file holes are divided into multiple groups according to different latitudes on the hemispherical tool holder, and each group includes multiple circumferentially distributed file holes; the installation length of the tool groove corresponding to the file holes in different latitudes is different, and the installation length of the tool groove corresponding to the file holes in higher latitudes is greater than that in lower latitudes; the countersunk through hole of the tool block includes a waist-shaped hole at the bottom and a clearance groove at the top, and the length of the tool block corresponding to the file holes in different latitudes is different, with the length of the tool block corresponding to the file holes in higher latitudes being greater than that in lower latitudes.

[0015] The method for replacing the blade of a disposable acetabular reamer involves disassembling the blade of the disposable acetabular reamer, cleaning and disinfecting it, and then installing it into a new hemispherical reamer holder for reuse; the original hemispherical reamer holder is discarded and disposed of as medical waste.

[0016] Furthermore, when the cutting block wears out, the cutting block on the file hole at the lowest latitude is discarded, the cutting block at the next higher latitude is transferred to the next latitude for continued use, and a new cutting block is used on the file hole at the highest latitude.

[0017] Compared with the prior art, the beneficial technical effects of the present invention are as follows:

[0018] This invention relates to a disposable acetabular file. The file uses a relatively inexpensive plastic hemispherical holder to support the file, ensuring single-use and preventing cross-infection between patients. It also reduces material costs, achieving economic efficiency for single-use applications. The disposable acetabular file of this invention uses a plastic hemispherical holder to support the file, reducing the cost of expensive metal materials and preventing cross-infection.

[0019] Furthermore, by using direct anchoring during injection molding, only the individual blades need to be positioned, and the blade installation is completed simultaneously with injection molding. Compared to machining stainless steel sheets into a hemispherical shape, injection molding is a mature and lower-cost process. Because it is only used once, the blade thickness can be reduced, improving cutting performance while reducing the amount of stainless steel used. By setting the cantilever end of the blade as an arc plate, the blade's resistance to deformation during filing is increased. The folded edge also improves the blade's strength and reduces the risk of hard bending deformation. Anchoring holes in the pre-embedded section of the blade increase its anchoring strength, preventing it from coming loose from the root. The blade block is installed into the tool groove with screws to act as a chip-cutting element during filing, enabling detachable installation. The discarded hemispherical tool holder can be removed, allowing for blade reuse and further improving the economic efficiency of this application. Moreover, the individual blade blocks have no complex structural features, making them easy to clean and disinfect, suitable for reuse, and preventing cross-contamination. By creating countersunk holes on the top surface of the cutting tool block, the nut height of the countersunk screw can be reduced, preventing interference. By adding thickened protrusions to the bottom surface of the threaded hole, the effective thread length of the threaded hole can be increased, preventing the countersunk screw from being pulled out. By appropriately setting different cutting tool lengths for different latitudes of filing holes, cutting tools that are not excessively worn at high latitudes can be switched to lower latitude installation positions for continued use, improving the service life of individual cutting tools. Adapting the installation length of the slotted hole and groove ensures that a universal screw method can be used to achieve the optimal ejection length after cutting tool switching for filing.

[0020] The present invention provides a disposable acetabular reamer blade replacement method. By rotating the installation position and using the same blade multiple times at different latitudes, the working life of a single blade is increased, waste is avoided, and the economy of the acetabular reamer of this application is further improved, and the cost of surgical instruments is reduced. Attached Figure Description

[0021] The present invention will be further described below with reference to the accompanying drawings.

[0022] Figure 1 This is a schematic diagram of the main structure of a disposable acetabular file according to Embodiment 1 of the present invention;

[0023] Figure 2 This is a schematic cross-sectional view of the blade position in Embodiment 1 of the present invention;

[0024] Figure 3 This is a front view structural diagram of a blade block installation position in Embodiment 2 of the present invention;

[0025] Figure 4 This is a schematic cross-sectional view of the blade block position in Embodiment 2 of the present invention;

[0026] Figure 5 This is a top view of the blade block structure in Embodiment 2 of the present invention.

[0027] Explanation of reference numerals in the attached diagram: 1. Hemispherical tool holder; 101. File hole; 102. Crosshead; 103. Tool groove; 1031. Positioning bottom edge; 104. Threaded hole; 105. Thickened protrusion; 2. Blade; 201. Folded edge; 202. Anchoring hole; 3. Tool block; 301. Waist-shaped hole; 302. Relief groove; 4. Countersunk screw. Detailed Implementation

[0028] The core of this invention is to provide a disposable acetabular file, which uses a plastic hemispherical holder to support the file, reducing the cost of expensive metal materials and avoiding cross-infection.

[0029] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of them. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0030] In the description of this invention, it should be understood that the terms "upper", "lower", "front", "rear", "left", "right", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0031] Refer to the attached diagram. Figure 1 This is a schematic diagram of the main structure of a disposable acetabular file according to Embodiment 1 of the present invention; Figure 2 This is a schematic cross-sectional view of the blade position in Embodiment 1 of the present invention; Figure 3 This is a front view structural diagram of a blade block installation position in Embodiment 2 of the present invention; Figure 4 This is a schematic cross-sectional view of the blade block position in Embodiment 2 of the present invention; Figure 5 This is a top view of the blade block structure in Embodiment 2 of the present invention.

[0032] Example 1

[0033] In one specific implementation, such as Figure 1 and Figure 2 As shown, the present invention relates to a disposable acetabular file hemispherical holder 1 and a file, which are no longer integrally molded from the same material. The hemispherical holder 1 is a plastic injection-molded hemispherical shell structure, such as ABS, PP, or PE material. The bottom of the hemispherical holder 1 is integrally injection-molded with a crosshead 102 for mounting. To improve strength, the thickness of the plastic shell is not less than 5 mm compared to the stainless steel shell. The shell of the hemispherical holder 1 has multiple filing holes 101. The file is fixedly connected to one side of the filing hole 101, and the cantilever end of the file extends into the filing hole 101 and protrudes from the outer spherical wall of the hemispherical holder 1.

[0034] The hemispherical acetabular file holder 1, made of relatively inexpensive plastic, serves to support the file, allowing for single-use and preventing cross-infection between patients. It also reduces material costs and achieves economic efficiency for single-use applications. This invention's disposable acetabular file uses a plastic hemispherical holder to support the file, reducing the cost of expensive metal materials and preventing cross-infection.

[0035] In one specific implementation of this embodiment, such as Figure 1 and Figure 2 As shown, the file specifically uses blade 2, which is made of 2Cr13 martensitic stainless steel or 3Cr13 stainless steel, and the thickness of blade 2 is no more than 2 mm. The root of blade 2 is directly injection molded and anchored in the shell material of the hemispherical tool holder 1, and the cantilever end face of blade 2 is set as the cutting edge.

[0036] By adopting the direct anchoring method during injection molding, it is only necessary to place each blade 2. The installation of the blade 2 is completed at the same time as injection molding. Compared with the machining of stainless steel sheets into hemispherical shapes, injection molding is a mature process with lower costs. Since it only needs to be used once, the thickness of the blade 2 can be reduced, improving cutting performance while reducing the amount of stainless steel material used.

[0037] Specifically, such as Figure 2 As shown, the cantilever end of the blade 2 is an arc-shaped plate with the convex surface facing outwards. Furthermore, both ends of the blade 2 in the width direction are provided with inwardly bent flanges 201.

[0038] Specifically, such as Figure 2 As shown, the embedded section of the blade 2 is provided with anchoring holes 202, and the anchoring holes 202 are filled with the shell material of the hemispherical blade holder 1. The anchoring holes 202 can be square holes or round holes.

[0039] By setting the cantilever end of the blade 2 as an arc plate, the deformation resistance of the blade 2 during the filing process is increased. At the same time, the setting of the folded edge 201 also improves the strength of the blade 2 and reduces the occurrence of hard bending deformation. By setting the anchoring hole 202 in the pre-embedded section of the blade 2, the anchoring strength of the blade 2 is increased, and it will not come out from the root.

[0040] The procedure for using the disposable acetabular file in this embodiment is as follows: During a total hip arthroplasty, the surgeon removes the disposable acetabular file from its disposable packaging. The file is then mounted onto the cross-head of a pneumatic or electric drill via the cross-head 102, inserted into the patient's acetabulum, and the switch is activated to rotate the hemispherical blade holder 1 at high speed to remove the acetabular cartilage until the required dimensions are met. At the end of the surgery, the disposable acetabular file is removed from the cross-head and disposed of in a medical waste bin.

[0041] Example 2

[0042] In the above embodiment, not only is the inexpensive plastic hemispherical blade holder 1 discarded, but the stainless steel blade 2 is also discarded, resulting in some waste. Therefore, further improvement is necessary. This embodiment is formed by revising the above embodiment 1. Figures 3-5 As shown, the file specifically uses a blade block 3. The filing hole 101 is a horseshoe-shaped through hole. The outer wall of the hemispherical tool holder 1 has a groove 103 recessed on one side of the straight edge of the filing hole 101. The blade block 3 is installed in the groove 103 by screws. The cantilever end of the blade block 3 extends into the filing hole 101 and is provided with a cutting edge.

[0043] Specifically, the thickness of the blade block 3 is not less than 3 mm, and the thickness of the plastic shell of the hemispherical blade holder 1 is 5 to 8 mm.

[0044] The blade block 3 is installed into the blade groove 103 by screws to serve as a chip-cutting element for filing, thus realizing the detachable installation of the blade block 3. The blade block 3 can be removed and reused after discarding the hemispherical blade holder 1, which further improves the economy of this application. Moreover, the single blade block 3 does not have complicated structural features, is easy to clean and disinfect, is suitable for reuse, and will not cause cross-contamination.

[0045] In one specific implementation of this embodiment, such as Figures 3-5 As shown, the top surface of the blade block 3 is provided with a countersunk through hole, and the countersunk screw 4 passes through the countersunk through hole and is threaded to the threaded hole 104 on the bottom surface of the blade groove 103.

[0046] Specifically, such as Figure 4 As shown, the hemispherical tool holder 1 has a thickened protrusion 105 added to the bottom surface at the location of the threaded hole 104.

[0047] By opening the countersunk through hole on the top surface of the blade block 3, the nut height of the countersunk screw 4 can be reduced, avoiding interference; by providing a thickened protrusion 105 on the bottom surface at the location of the threaded hole 104, the effective thread length of the threaded hole 104 can be increased, preventing the countersunk screw 4 from being pulled off.

[0048] In one specific embodiment of this example, the file holes 101 are divided into multiple groups according to different latitudes on the hemispherical tool holder 1. Each group includes multiple circumferentially distributed file holes 101. This design follows the hole arrangement form of the applicant's utility model patent CN209059342U, which has a more detailed technical description, and will not be repeated here.

[0049] Specifically, the installation length of the groove 103 corresponding to the file hole 101 is different for different latitudes, and the installation length of the groove 103 corresponding to the file hole 101 in high latitudes is greater than that in low latitudes.

[0050] Specifically, such as Figure 4 and Figure 5 As shown, in all the tool grooves 103, the distance from the center line of the threaded hole 104 to the straight edge of the horseshoe-shaped file hole 101 is the same; however, the distance from the positioning bottom edge 1031 behind the tool groove 103 to the center line of the threaded hole 104 is related to latitude, and the distance at this point in the tool groove 103 of low latitude is smaller than that in the tool groove 103 of high latitude.

[0051] Specifically, such as Figure 4 and Figure 5 As shown, the countersunk hole of the countersunk screw 3 includes a waist-shaped hole 301 at the bottom and a relief groove 302 at the top. The threaded section of the countersunk screw 4 passes through the waist-shaped hole 301, and the nut of the countersunk screw 4 is pressed into the relief groove 302. The length of the countersunk screw 3 corresponding to the file hole 101 of different latitudes is different, and the length of the countersunk screw 3 corresponding to the file hole 101 of higher latitudes is greater than that of the file hole 101 of lower latitudes.

[0052] Through long-term experience in using acetabular reamers, the applicant discovered that the first edge to wear down in existing acetabular reamers is often the lower-dimensional edge. When the lower-dimensional edge is severely worn and unusable, the entire reamer must be replaced. However, the higher-dimensional edge has not yet experienced significant wear and can still be used, thus leading to waste.

[0053] By appropriately setting different file hole 101 lengths corresponding to different latitudes, file blocks 3 that are not excessively worn at high latitudes can be switched to installation positions at low latitudes for continued use, thus improving the service life of a single file block 3. Through the adaptation of the installation length of the waist-shaped hole 301 and the groove 103, it can be ensured that a universal screw method can be used to achieve the optimal ejection length for filing after the file block 3 is switched.

[0054] Example 3

[0055] This invention also discloses a method for replacing the blade of a disposable acetabular reamer. After disassembling the blade 3 of the disposable acetabular reamer in Example 2 above, the blade 3 and the countersunk screw 4 are first cleaned and then disinfected, and then installed into a new hemispherical reamer holder 1 for reuse. Only the original hemispherical reamer holder 1 is discarded and treated as medical waste.

[0056] Specifically, when the cutting block 3 wears out, the cutting block 3 on the file hole 101 of the lowest latitude is discarded, the cutting block 3 of the higher latitude is transferred to the next latitude for continued use, and a new cutting block 3 is used on the file hole 101 of the highest latitude.

[0057] By rotating the installation position and using the same blade block 3 multiple times at different latitudes, the working life of a single blade block 3 is increased, waste is avoided, the economy of the acetabular reamer of this application is further improved, and the cost of surgical instruments is reduced.

[0058] In summary, the disposable acetabular file of this invention uses a relatively inexpensive plastic material to create a hemispherical blade holder 1, which supports the file. It is for single use only, avoiding cross-infection between patients; and it reduces material costs, achieving economic efficiency for single use. The disposable acetabular file of this invention uses a plastic hemispherical blade holder to support the file, reducing the cost of expensive metal materials and avoiding cross-infection. Furthermore, the direct anchoring method during injection molding only requires placing each blade 2; the installation of the blade 2 is completed simultaneously with injection molding. Injection molding is a more mature and less expensive process than machining stainless steel sheets into a hemispherical shape. Because it is only for single use, the thickness of the blade 2 can be reduced, improving cutting performance while reducing the amount of stainless steel used. By setting the cantilever end of the blade 2 as an arc plate, the deformation resistance of the blade 2 during filing is increased. The folded edge 201 also improves the strength of the blade 2 and reduces the risk of hard bending deformation. The anchoring hole 202 in the pre-embedded section of the blade 2 increases the anchoring strength of the blade 2, preventing it from coming loose from the root. The cutting block 3 is installed into the cutting groove 103 by screws to act as a chip-cutting element for filing, realizing the detachable installation of the cutting block 3. The discarded hemispherical tool holder 1 can be used to remove the cutting block 3 for reuse, further improving the economy of this application. Moreover, the single cutting block 3 does not have complex structural features, is easy to clean and disinfect, is suitable for reuse, and will not cause cross-contamination. By opening the countersunk through hole on the top surface of the cutting block 3, the nut height of the countersunk screw 4 can be reduced to avoid interference; by setting the thickened protrusion 105 on the bottom surface at the position of the threaded hole 104, the effective thread length of the threaded hole 104 can be increased to prevent the countersunk screw 4 from being pulled off. By reasonably setting the length of the cutting block 3 corresponding to the filing hole 101 at different latitudes, the cutting block 3 that is not excessively worn at high latitudes can be switched to the installation position at low latitudes for continued use, improving the service life of a single cutting block 3. By adapting the installation length through the waist-shaped hole 301 and the tool groove 103, it can be ensured that the tool block 3 can be automatically adjusted to the optimal ejection length for filing after switching using a common screw method.

[0059] The present invention provides a disposable acetabular reamer blade replacement method. By rotating the installation position and using the same blade 3 multiple times at different latitudes, the working life of a single blade 3 is increased, waste is avoided, the economy of the acetabular reamer of this application is further improved, and the cost of surgical instruments is reduced.

[0060] The various embodiments in this specification are described in a progressive manner, with each embodiment focusing on its differences from other embodiments. Similar or identical parts between embodiments can be referred to interchangeably. For the apparatus disclosed in the embodiments, since they correspond to the methods disclosed in the embodiments, the description is relatively simple; relevant parts can be referred to the method section.

[0061] The embodiments described above are merely preferred embodiments of the present invention and are not intended to limit the scope of the present invention. Various modifications and improvements made by those skilled in the art to the technical solutions of the present invention without departing from the spirit of the present invention should fall within the protection scope defined by the claims of the present invention.

Claims

1. A disposable acetabular reamer, characterized in that, include: The hemispherical tool holder (1) and the file are provided. The hemispherical tool holder (1) is a hemispherical shell structure formed by plastic injection molding. The bottom of the hemispherical tool holder (1) is integrally injection molded with a crosshead (102) for mounting. The shell of the hemispherical tool holder (1) is provided with multiple file holes (101). The file is fixedly connected to one side of the file hole (101). The cantilever end of the file is inserted into the file hole (101) and protrudes out of the outer spherical wall of the hemispherical tool holder (1). The file is specifically made of a blade block (3), the file hole (101) is a horseshoe-shaped through hole, and the outer wall of the hemispherical blade holder (1) is recessed and formed with a blade groove (103) on one side of the straight edge of the file hole (101). The blade block (3) is installed in the blade groove (103) by screws. The top surface of the blade block (3) is provided with a countersunk through hole, and the countersunk screw (4) passes through the countersunk through hole and is threaded to the threaded hole (104) on the bottom surface of the blade groove (103). The hemispherical tool holder (1) has a thickened protrusion (105) added to the bottom surface at the location of the threaded hole (104). The file holes (101) are divided into multiple groups according to different latitudes on the hemispherical tool holder (1), and each group includes multiple circumferentially distributed file holes (101); the installation length of the tool groove (103) corresponding to the file holes (101) of different latitudes is different, and the installation length of the tool groove (103) corresponding to the file holes (101) of higher latitudes is greater than that of the lower latitudes; the countersunk through hole of the tool block (3) includes a waist-shaped hole (301) at the bottom and a relief groove (302) at the top, and the length of the tool block (3) corresponding to the file holes (101) of different latitudes is different, and the length of the tool block (3) corresponding to the file holes (101) of higher latitudes is greater than that of the lower latitudes.

2. A method for replacing the blade of a disposable acetabular file, characterized in that, After the blade (3) of the disposable acetabular file in claim 1 is disassembled, cleaned and disinfected, it is installed into a new hemispherical blade holder (1) for reuse; the original hemispherical blade holder (1) is discarded and treated as medical waste.

3. The method for replacing the disposable acetabular file according to claim 2, characterized in that, When the blade (3) wears out, the blade (3) on the file hole (101) of the lowest latitude is discarded, the blade (3) of the higher latitude is transferred to the next latitude for continued use, and a new blade (3) is used on the file hole (101) of the highest latitude.

Images