A distal plug prosthesis for blocking the distal femoral medullary cavity opening

Abstract

The present invention provides a distal plug prosthesis for blocking the distal femoral medullary cavity opening, comprising a prosthesis column and an annular skirt, wherein the prosthesis column has a head end and a tail end; the head end is tapered and suitable for drilling; a cover sheet is formed on the edges around the tail end, and the plane where the cover sheet is located forms an angle of 30-40° with the central axis of the prosthesis column; the annular skirt is at least two circles, formed on the outer cylindrical surface of the middle part of the prosthesis column. The distal plug prosthesis for blocking the distal femoral medullary cavity opening provided by the present invention fills the gap in the industry. During knee replacement surgery, when intramedullary positioning is used at the femoral end, after completing the positioning or before installing the prosthesis, a distal plug prosthesis of suitable specifications is selected to be directly plugged into the distal femoral medullary cavity opening, saving operation time, and there is no need to grind the patient's osteotomy block during the operation to re-form the bone plug. Moreover, the distal plug prosthesis is tightly sealed after being plugged in, and is not easy to fall off, be plugged too deep or fall into the medullary cavity, and can effectively block the distal femoral medullary cavity opening.

Description

Technical Field

[0001] The invention relates to the technical field of orthopedic osteotomy prostheses, and in particular to a distal plug prosthesis capable of plugging a femoral medullary foramen exposed due to osteotomy. Background Art

[0002] Knee replacement is the use of artificial biological materials to replace and rebuild the joint surface damaged by disease. Its purpose is to remove the lesion to relieve symptoms, eliminate pain, restore and improve joint function, and improve the quality of life. Modern artificial knee replacement surgery began in the 1960s. After more than half a century of continuous development, it has become a relatively ideal and effective treatment for advanced joint diseases. In recent years, with the development of science and technology, knee replacement has been greatly improved and enhanced from surgical techniques to prosthesis design concepts.

[0003] An important purpose of artificial knee replacement is to reconstruct and restore the force line of the lower limbs. Poor alignment can easily lead to limited knee joint movement, anterior knee pain, prosthesis instability, loosening and wear, patellofemoral joint dysfunction, etc. At present, femoral osteotomy in knee surgery is used by most surgeons because femoral intramedullary positioning is more accurate in guiding distal femoral osteotomy. Femoral intramedullary positioning is to determine the femoral valgus angle by observing the X-ray of the patient's leg before surgery. During the operation, the condylar line and the anterior-posterior axis are used as references to determine the external rotation angle, and the force line measurement rod is used to observe whether the femoral force line is accurately aligned.

[0004] refer to Figure 1-4 As shown in the figure, the specific steps of distal femoral osteotomy are: first flex the knee joint 90°, mark the Install line 01 and the Whiteside line 02 at the distal end of the femur, the intersection of which is the apex of the intercondylar notch 03, and the entrance of the femoral medullary cavity is about 3-5mm inside the apex of the intercondylar notch 03; after determining the entrance, use an 8mm drill bit 04 to open the entrance of the medullary cavity; when the drill bit 04 enters, touch the distal side of the femoral shaft to keep the direction correct and avoid hitting the cortex. Figure 5-6 As shown, assemble the femoral valgus positioner 05 and the distal femoral osteotomy guide 06, screw the valgus positioner handle 07, and generally set the default osteotomy thickness to 9mm; fix the femoral valgus positioner 05 to the femoral intramedullary rod 08, and slowly and unimpededly insert it into the center of the medullary cavity until the isthmus; at this time, the bone marrow flows out from the groove of the intramedullary rod, reducing the intramedullary pressure, and the intramedullary rod itself does not bend. According to the preoperative X-ray, set the appropriate valgus angle, the same as the healthy side, and the Chinese recommend 6°. Reference Figure 7 As shown, fix the distal osteotomy guide plate 06 on the femoral condyle, and quickly insert two fixation nails 09 to keep them horizontal and close, usually tighter on the inside. At this time, the intramedullary rod and locator can be removed to confirm the femoral force line, such as Figure 8As shown, the force line rod 010 is connected to the osteotomy groove force line guide device. When the distal end of the force line rod indicates the femoral head rotation center 011, the position is considered to be correct.

[0005] When the operation is performed to install the prosthesis, the medullary cavity opening 012 at the distal end of the femur is currently filled with the cut bone 013, which is trimmed into a round plug 014 to protect the intramedullary tissue from external bacterial infection (reference Figure 9-12 However, the current problem is that knee replacement surgery takes a long time, generally about 2 hours, and the cut bone fragments are separated from the body for a long time, which may cause infection risks if they are re-implanted. In addition, the cut bone fragments need to be temporarily trimmed, which increases the operation time. The trimmed bone fragments are difficult to completely match the medullary cavity opening, resulting in poor sealing. Summary of the invention

[0006] Therefore, the technical problem to be solved by the present invention is to overcome the problem that there is no prosthesis specifically used for filling the distal femoral medullary cavity opening in the prior art, and that the bone blocks cut off from the patient need to be temporarily trimmed during surgery, which not only increases the operation time, but also makes it difficult for the trimmed bone blocks to match the medullary cavity opening, resulting in a technical defect of poor sealing, thereby providing a distal plug prosthesis for sealing the distal femoral medullary cavity opening.

[0007] To this end, the present invention provides a distal plug prosthesis for blocking the distal medullary cavity opening of the femur, comprising:

[0008] The prosthesis column has a head end and a tail end; the head end is tapered and suitable for drilling; the edges of the tail end are formed with a cover sheet, and the plane where the cover sheet is located forms an angle of 30-40° with the central axis of the prosthesis column;

[0009] An annular skirt, at least in two circles, is formed on the outer cylindrical surface of the middle portion of the prosthetic column.

[0010] As a preferred solution, an operation hole is opened in the middle of the tail end of the prosthetic column, and the operation hole is a polygonal structure.

[0011] As a preferred solution, the cover sheet is in the shape of an ellipse or a rectangle with four chamfered corners.

[0012] As a preferred solution, the covering sheet has a width of 10-20 mm and a length of 15-25 mm.

[0013] As a preferred solution, the center of the rear end of the prosthetic column substantially coincides with the center of the covering sheet.

[0014] As a preferred solution, the diameter of the annular skirt remains the same or gradually increases from the head end to the tail end.

[0015] As a preferred solution, at least one notch is formed on at least one of the annular skirts.

[0016] As a preferred solution, the notch is triangular or trapezoidal, and the opening size of the notch gradually decreases in the direction approaching the prosthesis column.

[0017] As a preferred solution, the body of the prosthetic column or the portion from the head end of the prosthetic column to the annular skirt closest to the head end is provided with a plurality of long grooves on the outer side wall of the prosthetic column along the axial direction of the prosthetic column.

[0018] As a preferred solution, the cross-section of the long groove is triangular or trapezoidal, and the opening size of the long groove gradually decreases along the direction gradually approaching the central axis of the prosthesis column.

[0019] The technical solution provided by the present invention has the following advantages:

[0020] The distal plug prosthesis for sealing the distal medullary cavity opening of the femur of the present invention comprises a prosthetic column and an annular skirt, wherein the prosthetic column has a head end and a tail end; the head end is tapered and suitable for drilling; a cover sheet is formed on the edges around the tail end, and the plane where the cover sheet is located forms an angle of 30-40° with the central axis of the prosthetic column; the annular skirt has at least two circles, which are formed on the outer cylindrical surface of the middle part of the prosthetic column. The distal plug prosthesis for blocking the distal femoral medullary cavity opening provided by the present invention fills a gap in the industry. During knee replacement surgery, when intramedullary positioning is used at the femoral end, after positioning is completed or before the prosthesis is installed, a distal plug prosthesis of appropriate specifications can be selected to be directly plugged into the distal opening of the femoral medullary cavity. This is convenient and quick, and saves surgical time. There is no need to grind the patient's osteotomy block to re-form a bone plug during the operation. Moreover, the distal plug prosthesis of this embodiment is tightly sealed after insertion and is not easy to fall off or be inserted too deeply or fall into the medullary cavity. It can effectively block the distal femoral medullary cavity opening, reduce femoral medullary cavity bleeding after knee replacement, and protect the medullary cavity from infection. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to more clearly illustrate the technical solutions in the prior art or the specific implementation manner of the present invention, the drawings used in the description of the prior art or the specific implementation manner are briefly introduced below.

[0022] Figure 1 It is a structural diagram that marks the apex of the intercondylar fossa at the distal end of the femur to find the entrance to the femoral medullary cavity.

[0023] Figure 2 It is a schematic diagram of the structure of using a drill bit to drill an opening at the entrance.

[0024] Figure 3 It is a schematic diagram of the structure of the drill bit moving in the distal femur.

[0025] Figure 4 yes Figure 3 Another angle view of .

[0026] Figure 5 It is a schematic diagram of the structure of the assembly of a femoral valgus positioner and a distal femoral osteotomy guide.

[0027] Figure 6 Yes Figure 5 Schematic diagram of the structure of the femoral intramedullary rod inserted into the medullary canal opening.

[0028] Figure 7 It is a schematic diagram of the structure for fixing the distal osteotomy guide plate on the femoral condyle.

[0029] Figure 8 It is a schematic diagram of the structure of using force line rod to correct force line.

[0030] Fig. 9 This is a schematic diagram of the structure with the medullary cavity opening exposed after osteotomy is completed at the distal end of the femur.

[0031] Fig.10 It is a schematic diagram of the structure of selecting cut bones for grinding.

[0032] Fig.11 It is a schematic diagram of the structure of installing the polished bone block into the medullary cavity opening.

[0033] Fig.12 It is a schematic diagram of the structure after the polished bone block is knocked into the medullary cavity opening.

[0034] Fig.13 It is a schematic diagram of the structure of the distal plug prosthesis in this application.

[0035] Fig.14 yes Fig.13 Another angle view of .

[0036] Fig.15 yes Fig.13 Another structural diagram of .

[0037] Fig.16 It is another structural schematic diagram of the distal plug prosthesis in this application.

[0038] Figure markings: 01, Install line; 02, Whiteside line; 03, intercondylar notch apex; 04, drill bit; 05, femoral valgus locator; 06, distal femoral osteotomy guide; 07, handle; 08, femoral intramedullary rod; 09, fixation nail; 010, force line rod; 011, femoral head rotation center; 012, medullary cavity opening; 013, cut bone; 014, circular plug; 1, prosthetic column; 11, head end; 12, tail end; 13, operation hole; 14, long groove; 2, cover plate; 3, annular skirt; 31, notch. DETAILED DESCRIPTION

[0039] In order to make those skilled in the art better understand the present solution, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative work should fall within the scope of protection of the present application.

[0040] It should be noted that the terms "first", "second", etc. in the claims and description of the present application are used to distinguish similar objects, rather than to describe a specific order or sequence. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions, for example, a process, method, system, product or device that includes a series of steps or units is not limited to those steps or units clearly listed, but may also include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0041] In the present application, the terms "upper", "lower", "left", "right", "front", "back", "top", "bottom", "inside", "outside", "middle", "vertical", "horizontal", "lateral", "longitudinal" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings. These terms are mainly intended to better describe the present application and its embodiments, and are not intended to limit the indicated devices, elements or components to have a specific orientation, or to be constructed and operated in a specific orientation. In addition, in addition to being used to indicate orientation or positional relationships, some of the above terms may also be used to indicate other meanings. For example, the term "upper" may also be used to indicate a certain dependency or connection relationship in some cases. For those skilled in the art, the specific meanings of these terms in the present application can be understood according to the specific circumstances. In addition, the term "multiple" should mean two or more. It should be noted that the embodiments in the present application and the features in the embodiments may be combined with each other without conflict.

[0042] The present application will be described in detail below with reference to the accompanying drawings and in combination with embodiments. Example

[0043] This embodiment provides a distal plug prosthesis for plugging the distal femoral medullary cavity opening, such as Figure 13-14As shown, it includes a prosthetic column 1, which has a head end 11 and a tail end 12; wherein the head end 11 is conical, with a pointed tip at the front, suitable for drilling into the medullary cavity from the position of the medullary cavity opening; a cover sheet 2 is formed on the edges around the tail end 12, and after the prosthetic column 1 is completely drilled into the medullary cavity, the cover sheet 2 at the tail end 12 is left around the medullary cavity opening to play a further covering and shielding role; the plane where the cover sheet 2 is located forms an angle of about 30-40° with the central axis of the prosthetic column 1 to match the angle of the osteotomy surface; a plurality of annular skirts 3 are formed on the outer cylindrical surface of the middle part of the prosthetic column 1, and when the prosthetic column 1 is inserted into the medullary cavity, the annular skirts 3 are deformed and elastically squeezed between the medullary cavity and the prosthetic column 1, thereby enhancing the firmness of the distal plug prosthesis installed in the medullary cavity.

[0044] The distal plug prosthesis provided in this embodiment for sealing the distal femoral medullary cavity opening fills a gap in the industry. During knee replacement surgery, when intramedullary positioning is used at the femoral end, after positioning is completed or before the prosthesis is installed, a distal plug prosthesis of appropriate specifications can be selected to be directly inserted into the distal opening of the femoral medullary cavity. This is convenient and quick, and saves surgical time. There is no need to grind the patient's osteotomy fragments to re-form a bone plug during the operation. Moreover, the distal plug prosthesis of this embodiment is tightly sealed after insertion, and is not easy to fall off or be inserted too deep or fall into the medullary cavity. It can effectively seal the distal femoral medullary cavity opening and protect the medullary cavity from infection.

[0045] Furthermore, an operation hole 13 is opened in the middle of the tail end of the prosthetic column 1, and the inner cavity of the operation hole 13 is a polygonal structure. The operation hole 13 with this structure is convenient for the operator to screw the distal plug so that the distal plug can enter the medullary cavity more easily or maintain a suitable rotation angle after entering the medullary cavity, so that the position of the cover plate 2 is appropriate.

[0046] Further, the cover sheet 2 is oval or rectangular with four corners being arc-shaped chamfers, so as to fit against the osteotomy surface and maximize the covering area. The width of the cover sheet 2 can be designed to be 10-20 mm, and the length can be designed to be 15-25 mm, so as to match the femur size of most patients.

[0047] The center of the rear end of the prosthetic column 1 is substantially coincident with the center of the covering sheet 2, thereby ensuring that the covering sheet 2 extends around the center of the rear end of the prosthetic column 1 to achieve better and more comprehensive covering of the medullary cavity opening.

[0048] The diameter of the annular skirt 3 remains the same or gradually increases in the direction from the head end 11 to the tail end 12, and can be selected according to the characteristics of the patient's medullary cavity. For example, if the inner diameter of the medullary cavity of the distal end of the femur remains basically unchanged from bottom to top, a distal plug with the above-mentioned annular skirt 3 that remains the same can be selected. If the inner diameter of the medullary cavity of the distal end of the femur gradually decreases from bottom to top or the open end is difficult to insert, the distal plug with the above-mentioned gradually increasing annular skirt 3 can be selected.

[0049] Preferably, Fig.15As shown, at least one notch 31 is formed on the annular skirt 3. When the distal plug prosthesis is inserted into the medullary cavity opening, the positions of the notches 31 of the annular skirt 3 can be staggered and overlapped. When the outer diameter of the annular skirt 3 is larger and the outer diameter of the medullary cavity is slightly smaller, a distal plug prosthesis with a notch 31 can be selected.

[0050] Specifically, the notch 31 may be in the shape of a triangle or a trapezoid, and the opening size of the notch 31 gradually decreases as it approaches the prosthetic column 1 .

[0051] Preferably, Fig.16 As shown, the body of the prosthetic column 1 or the portion from the head end 11 of the prosthetic column 1 to the annular skirt 3 closest to the head end 11, along the axial direction of the prosthetic column, a plurality of long grooves 14 are opened on the outer wall of the prosthetic column 1; generally speaking, in order to avoid the distal plug prosthesis from being installed loosely, it is necessary to set the outer diameter of the prosthetic column 1 to be basically the same as the inner diameter of the medullary cavity. When the inner diameter of the patient's medullary cavity is smaller than the outer diameter of the prosthetic column 1 of the distal plug closest to the specification, a distal plug prosthesis with a long groove 14 structure can be selected. During the insertion process, the portion from the head end 11 of the distal plug to the annular skirt 3 closest to the head end 11, or directly the body of the prosthetic column 1, can be reduced in diameter, so that it can be inserted into the medullary cavity with a smaller inner diameter for a secure installation.

[0052] Specifically, the cross section of the long groove 14 may be triangular or trapezoidal, and the opening size of the long groove 14 gradually decreases in a direction gradually approaching the central axis of the prosthetic column 1 .

[0053] Obviously, the above embodiments are merely examples for clear explanation, and are not intended to limit the implementation methods. For ordinary technicians in the relevant field, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all the implementation methods here. The obvious changes or modifications derived from them are still within the protection scope of this innovative technical solution.

Claims

1. A distal plug prosthesis for blocking the distal medullary cavity opening of a femur, characterized in that: include: A prosthetic column (1) having a head end (11) and a tail end (12); the head end (11) is tapered and suitable for drilling; a cover sheet (2) is formed around the edges of the tail end (12), and the plane where the cover sheet (2) is located forms an angle of 30-40° with the central axis of the prosthetic column (1); An annular skirt (3), having at least two circles, is formed on the outer cylindrical surface of the middle part of the prosthetic column (1); An operating hole (13) is provided in the middle of the rear end of the prosthetic column (1), and the operating hole (13) is a polygonal structure.

2. The distal plug prosthesis according to claim 1, characterized in that: The covering sheet (2) is in the shape of an ellipse or a rectangle with four chamfered corners.

3. The distal plug prosthesis according to claim 1, characterized in that: The covering sheet (2) has a width of 10-20 mm and a length of 15-25 mm.

4. The distal plug prosthesis according to claim 3, characterized in that: The center of the rear end (12) of the prosthetic column (1) substantially coincides with the center of the covering sheet (2).

5. The distal plug prosthesis according to claim 1, characterized in that: The diameter of the annular skirt (3) remains the same or gradually increases in the direction from the head end (11) to the tail end (12).

6. The distal plug prosthesis according to claim 5, characterized in that: At least one notch (31) is formed on at least one of the annular skirts (3).

7. The distal plug prosthesis according to claim 6, characterized in that: The notch (31) is triangular or trapezoidal, and the opening size of the notch (31) gradually decreases in a direction gradually approaching the prosthetic column (1).

8. The distal plug prosthesis according to claim 1, characterized in that: The column body of the prosthetic column (1) or the portion from the head end (11) of the prosthetic column (1) to the annular skirt (3) closest to the head end (11) is provided with a plurality of long grooves (14) on the outer side wall of the prosthetic column (1) along the axial direction of the prosthetic column (1).

9. The distal plug prosthesis according to claim 8, characterized in that: The cross section of the long groove (14) is triangular or trapezoidal, and the opening size of the long groove (14) gradually decreases in a direction gradually approaching the central axis of the prosthesis column (1).

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